| /* |
| * Copyright (C) 2007 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package android.widget; |
| |
| import android.content.Context; |
| import android.content.Intent; |
| import android.content.res.TypedArray; |
| import android.graphics.Rect; |
| import android.util.AttributeSet; |
| import android.view.Gravity; |
| import android.view.KeyEvent; |
| import android.view.SoundEffectConstants; |
| import android.view.View; |
| import android.view.ViewDebug; |
| import android.view.ViewGroup; |
| import android.view.accessibility.AccessibilityEvent; |
| import android.view.accessibility.AccessibilityNodeInfo; |
| import android.view.animation.GridLayoutAnimationController; |
| import android.widget.RemoteViews.RemoteView; |
| |
| |
| /** |
| * A view that shows items in two-dimensional scrolling grid. The items in the |
| * grid come from the {@link ListAdapter} associated with this view. |
| * |
| * <p>See the <a href="{@docRoot}guide/topics/ui/layout/gridview.html">Grid |
| * View</a> guide.</p> |
| * |
| * @attr ref android.R.styleable#GridView_horizontalSpacing |
| * @attr ref android.R.styleable#GridView_verticalSpacing |
| * @attr ref android.R.styleable#GridView_stretchMode |
| * @attr ref android.R.styleable#GridView_columnWidth |
| * @attr ref android.R.styleable#GridView_numColumns |
| * @attr ref android.R.styleable#GridView_gravity |
| */ |
| @RemoteView |
| public class GridView extends AbsListView { |
| /** |
| * Disables stretching. |
| * |
| * @see #setStretchMode(int) |
| */ |
| public static final int NO_STRETCH = 0; |
| /** |
| * Stretches the spacing between columns. |
| * |
| * @see #setStretchMode(int) |
| */ |
| public static final int STRETCH_SPACING = 1; |
| /** |
| * Stretches columns. |
| * |
| * @see #setStretchMode(int) |
| */ |
| public static final int STRETCH_COLUMN_WIDTH = 2; |
| /** |
| * Stretches the spacing between columns. The spacing is uniform. |
| * |
| * @see #setStretchMode(int) |
| */ |
| public static final int STRETCH_SPACING_UNIFORM = 3; |
| |
| /** |
| * Creates as many columns as can fit on screen. |
| * |
| * @see #setNumColumns(int) |
| */ |
| public static final int AUTO_FIT = -1; |
| |
| private int mNumColumns = AUTO_FIT; |
| |
| private int mHorizontalSpacing = 0; |
| private int mRequestedHorizontalSpacing; |
| private int mVerticalSpacing = 0; |
| private int mStretchMode = STRETCH_COLUMN_WIDTH; |
| private int mColumnWidth; |
| private int mRequestedColumnWidth; |
| private int mRequestedNumColumns; |
| |
| private View mReferenceView = null; |
| private View mReferenceViewInSelectedRow = null; |
| |
| private int mGravity = Gravity.START; |
| |
| private final Rect mTempRect = new Rect(); |
| |
| public GridView(Context context) { |
| this(context, null); |
| } |
| |
| public GridView(Context context, AttributeSet attrs) { |
| this(context, attrs, com.android.internal.R.attr.gridViewStyle); |
| } |
| |
| public GridView(Context context, AttributeSet attrs, int defStyle) { |
| super(context, attrs, defStyle); |
| |
| TypedArray a = context.obtainStyledAttributes(attrs, |
| com.android.internal.R.styleable.GridView, defStyle, 0); |
| |
| int hSpacing = a.getDimensionPixelOffset( |
| com.android.internal.R.styleable.GridView_horizontalSpacing, 0); |
| setHorizontalSpacing(hSpacing); |
| |
| int vSpacing = a.getDimensionPixelOffset( |
| com.android.internal.R.styleable.GridView_verticalSpacing, 0); |
| setVerticalSpacing(vSpacing); |
| |
| int index = a.getInt(com.android.internal.R.styleable.GridView_stretchMode, STRETCH_COLUMN_WIDTH); |
| if (index >= 0) { |
| setStretchMode(index); |
| } |
| |
| int columnWidth = a.getDimensionPixelOffset(com.android.internal.R.styleable.GridView_columnWidth, -1); |
| if (columnWidth > 0) { |
| setColumnWidth(columnWidth); |
| } |
| |
| int numColumns = a.getInt(com.android.internal.R.styleable.GridView_numColumns, 1); |
| setNumColumns(numColumns); |
| |
| index = a.getInt(com.android.internal.R.styleable.GridView_gravity, -1); |
| if (index >= 0) { |
| setGravity(index); |
| } |
| |
| a.recycle(); |
| } |
| |
| @Override |
| public ListAdapter getAdapter() { |
| return mAdapter; |
| } |
| |
| /** |
| * Sets up this AbsListView to use a remote views adapter which connects to a RemoteViewsService |
| * through the specified intent. |
| * @param intent the intent used to identify the RemoteViewsService for the adapter to connect to. |
| */ |
| @android.view.RemotableViewMethod |
| public void setRemoteViewsAdapter(Intent intent) { |
| super.setRemoteViewsAdapter(intent); |
| } |
| |
| /** |
| * Sets the data behind this GridView. |
| * |
| * @param adapter the adapter providing the grid's data |
| */ |
| @Override |
| public void setAdapter(ListAdapter adapter) { |
| if (mAdapter != null && mDataSetObserver != null) { |
| mAdapter.unregisterDataSetObserver(mDataSetObserver); |
| } |
| |
| resetList(); |
| mRecycler.clear(); |
| mAdapter = adapter; |
| |
| mOldSelectedPosition = INVALID_POSITION; |
| mOldSelectedRowId = INVALID_ROW_ID; |
| |
| // AbsListView#setAdapter will update choice mode states. |
| super.setAdapter(adapter); |
| |
| if (mAdapter != null) { |
| mOldItemCount = mItemCount; |
| mItemCount = mAdapter.getCount(); |
| mDataChanged = true; |
| checkFocus(); |
| |
| mDataSetObserver = new AdapterDataSetObserver(); |
| mAdapter.registerDataSetObserver(mDataSetObserver); |
| |
| mRecycler.setViewTypeCount(mAdapter.getViewTypeCount()); |
| |
| int position; |
| if (mStackFromBottom) { |
| position = lookForSelectablePosition(mItemCount - 1, false); |
| } else { |
| position = lookForSelectablePosition(0, true); |
| } |
| setSelectedPositionInt(position); |
| setNextSelectedPositionInt(position); |
| checkSelectionChanged(); |
| } else { |
| checkFocus(); |
| // Nothing selected |
| checkSelectionChanged(); |
| } |
| |
| requestLayout(); |
| } |
| |
| @Override |
| int lookForSelectablePosition(int position, boolean lookDown) { |
| final ListAdapter adapter = mAdapter; |
| if (adapter == null || isInTouchMode()) { |
| return INVALID_POSITION; |
| } |
| |
| if (position < 0 || position >= mItemCount) { |
| return INVALID_POSITION; |
| } |
| return position; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| void fillGap(boolean down) { |
| final int numColumns = mNumColumns; |
| final int verticalSpacing = mVerticalSpacing; |
| |
| final int count = getChildCount(); |
| |
| if (down) { |
| int paddingTop = 0; |
| if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { |
| paddingTop = getListPaddingTop(); |
| } |
| final int startOffset = count > 0 ? |
| getChildAt(count - 1).getBottom() + verticalSpacing : paddingTop; |
| int position = mFirstPosition + count; |
| if (mStackFromBottom) { |
| position += numColumns - 1; |
| } |
| fillDown(position, startOffset); |
| correctTooHigh(numColumns, verticalSpacing, getChildCount()); |
| } else { |
| int paddingBottom = 0; |
| if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { |
| paddingBottom = getListPaddingBottom(); |
| } |
| final int startOffset = count > 0 ? |
| getChildAt(0).getTop() - verticalSpacing : getHeight() - paddingBottom; |
| int position = mFirstPosition; |
| if (!mStackFromBottom) { |
| position -= numColumns; |
| } else { |
| position--; |
| } |
| fillUp(position, startOffset); |
| correctTooLow(numColumns, verticalSpacing, getChildCount()); |
| } |
| } |
| |
| /** |
| * Fills the list from pos down to the end of the list view. |
| * |
| * @param pos The first position to put in the list |
| * |
| * @param nextTop The location where the top of the item associated with pos |
| * should be drawn |
| * |
| * @return The view that is currently selected, if it happens to be in the |
| * range that we draw. |
| */ |
| private View fillDown(int pos, int nextTop) { |
| View selectedView = null; |
| |
| int end = (mBottom - mTop); |
| if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { |
| end -= mListPadding.bottom; |
| } |
| |
| while (nextTop < end && pos < mItemCount) { |
| View temp = makeRow(pos, nextTop, true); |
| if (temp != null) { |
| selectedView = temp; |
| } |
| |
| // mReferenceView will change with each call to makeRow() |
| // do not cache in a local variable outside of this loop |
| nextTop = mReferenceView.getBottom() + mVerticalSpacing; |
| |
| pos += mNumColumns; |
| } |
| |
| setVisibleRangeHint(mFirstPosition, mFirstPosition + getChildCount() - 1); |
| return selectedView; |
| } |
| |
| private View makeRow(int startPos, int y, boolean flow) { |
| final int columnWidth = mColumnWidth; |
| final int horizontalSpacing = mHorizontalSpacing; |
| |
| final boolean isLayoutRtl = isLayoutRtl(); |
| |
| int last; |
| int nextLeft; |
| |
| if (isLayoutRtl) { |
| nextLeft = getWidth() - mListPadding.right - columnWidth - |
| ((mStretchMode == STRETCH_SPACING_UNIFORM) ? horizontalSpacing : 0); |
| } else { |
| nextLeft = mListPadding.left + |
| ((mStretchMode == STRETCH_SPACING_UNIFORM) ? horizontalSpacing : 0); |
| } |
| |
| if (!mStackFromBottom) { |
| last = Math.min(startPos + mNumColumns, mItemCount); |
| } else { |
| last = startPos + 1; |
| startPos = Math.max(0, startPos - mNumColumns + 1); |
| |
| if (last - startPos < mNumColumns) { |
| final int deltaLeft = (mNumColumns - (last - startPos)) * (columnWidth + horizontalSpacing); |
| nextLeft += (isLayoutRtl ? -1 : +1) * deltaLeft; |
| } |
| } |
| |
| View selectedView = null; |
| |
| final boolean hasFocus = shouldShowSelector(); |
| final boolean inClick = touchModeDrawsInPressedState(); |
| final int selectedPosition = mSelectedPosition; |
| |
| View child = null; |
| for (int pos = startPos; pos < last; pos++) { |
| // is this the selected item? |
| boolean selected = pos == selectedPosition; |
| // does the list view have focus or contain focus |
| |
| final int where = flow ? -1 : pos - startPos; |
| child = makeAndAddView(pos, y, flow, nextLeft, selected, where); |
| |
| nextLeft += (isLayoutRtl ? -1 : +1) * columnWidth; |
| if (pos < last - 1) { |
| nextLeft += horizontalSpacing; |
| } |
| |
| if (selected && (hasFocus || inClick)) { |
| selectedView = child; |
| } |
| } |
| |
| mReferenceView = child; |
| |
| if (selectedView != null) { |
| mReferenceViewInSelectedRow = mReferenceView; |
| } |
| |
| return selectedView; |
| } |
| |
| /** |
| * Fills the list from pos up to the top of the list view. |
| * |
| * @param pos The first position to put in the list |
| * |
| * @param nextBottom The location where the bottom of the item associated |
| * with pos should be drawn |
| * |
| * @return The view that is currently selected |
| */ |
| private View fillUp(int pos, int nextBottom) { |
| View selectedView = null; |
| |
| int end = 0; |
| if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { |
| end = mListPadding.top; |
| } |
| |
| while (nextBottom > end && pos >= 0) { |
| |
| View temp = makeRow(pos, nextBottom, false); |
| if (temp != null) { |
| selectedView = temp; |
| } |
| |
| nextBottom = mReferenceView.getTop() - mVerticalSpacing; |
| |
| mFirstPosition = pos; |
| |
| pos -= mNumColumns; |
| } |
| |
| if (mStackFromBottom) { |
| mFirstPosition = Math.max(0, pos + 1); |
| } |
| |
| setVisibleRangeHint(mFirstPosition, mFirstPosition + getChildCount() - 1); |
| return selectedView; |
| } |
| |
| /** |
| * Fills the list from top to bottom, starting with mFirstPosition |
| * |
| * @param nextTop The location where the top of the first item should be |
| * drawn |
| * |
| * @return The view that is currently selected |
| */ |
| private View fillFromTop(int nextTop) { |
| mFirstPosition = Math.min(mFirstPosition, mSelectedPosition); |
| mFirstPosition = Math.min(mFirstPosition, mItemCount - 1); |
| if (mFirstPosition < 0) { |
| mFirstPosition = 0; |
| } |
| mFirstPosition -= mFirstPosition % mNumColumns; |
| return fillDown(mFirstPosition, nextTop); |
| } |
| |
| private View fillFromBottom(int lastPosition, int nextBottom) { |
| lastPosition = Math.max(lastPosition, mSelectedPosition); |
| lastPosition = Math.min(lastPosition, mItemCount - 1); |
| |
| final int invertedPosition = mItemCount - 1 - lastPosition; |
| lastPosition = mItemCount - 1 - (invertedPosition - (invertedPosition % mNumColumns)); |
| |
| return fillUp(lastPosition, nextBottom); |
| } |
| |
| private View fillSelection(int childrenTop, int childrenBottom) { |
| final int selectedPosition = reconcileSelectedPosition(); |
| final int numColumns = mNumColumns; |
| final int verticalSpacing = mVerticalSpacing; |
| |
| int rowStart; |
| int rowEnd = -1; |
| |
| if (!mStackFromBottom) { |
| rowStart = selectedPosition - (selectedPosition % numColumns); |
| } else { |
| final int invertedSelection = mItemCount - 1 - selectedPosition; |
| |
| rowEnd = mItemCount - 1 - (invertedSelection - (invertedSelection % numColumns)); |
| rowStart = Math.max(0, rowEnd - numColumns + 1); |
| } |
| |
| final int fadingEdgeLength = getVerticalFadingEdgeLength(); |
| final int topSelectionPixel = getTopSelectionPixel(childrenTop, fadingEdgeLength, rowStart); |
| |
| final View sel = makeRow(mStackFromBottom ? rowEnd : rowStart, topSelectionPixel, true); |
| mFirstPosition = rowStart; |
| |
| final View referenceView = mReferenceView; |
| |
| if (!mStackFromBottom) { |
| fillDown(rowStart + numColumns, referenceView.getBottom() + verticalSpacing); |
| pinToBottom(childrenBottom); |
| fillUp(rowStart - numColumns, referenceView.getTop() - verticalSpacing); |
| adjustViewsUpOrDown(); |
| } else { |
| final int bottomSelectionPixel = getBottomSelectionPixel(childrenBottom, |
| fadingEdgeLength, numColumns, rowStart); |
| final int offset = bottomSelectionPixel - referenceView.getBottom(); |
| offsetChildrenTopAndBottom(offset); |
| fillUp(rowStart - 1, referenceView.getTop() - verticalSpacing); |
| pinToTop(childrenTop); |
| fillDown(rowEnd + numColumns, referenceView.getBottom() + verticalSpacing); |
| adjustViewsUpOrDown(); |
| } |
| |
| return sel; |
| } |
| |
| private void pinToTop(int childrenTop) { |
| if (mFirstPosition == 0) { |
| final int top = getChildAt(0).getTop(); |
| final int offset = childrenTop - top; |
| if (offset < 0) { |
| offsetChildrenTopAndBottom(offset); |
| } |
| } |
| } |
| |
| private void pinToBottom(int childrenBottom) { |
| final int count = getChildCount(); |
| if (mFirstPosition + count == mItemCount) { |
| final int bottom = getChildAt(count - 1).getBottom(); |
| final int offset = childrenBottom - bottom; |
| if (offset > 0) { |
| offsetChildrenTopAndBottom(offset); |
| } |
| } |
| } |
| |
| @Override |
| int findMotionRow(int y) { |
| final int childCount = getChildCount(); |
| if (childCount > 0) { |
| |
| final int numColumns = mNumColumns; |
| if (!mStackFromBottom) { |
| for (int i = 0; i < childCount; i += numColumns) { |
| if (y <= getChildAt(i).getBottom()) { |
| return mFirstPosition + i; |
| } |
| } |
| } else { |
| for (int i = childCount - 1; i >= 0; i -= numColumns) { |
| if (y >= getChildAt(i).getTop()) { |
| return mFirstPosition + i; |
| } |
| } |
| } |
| } |
| return INVALID_POSITION; |
| } |
| |
| /** |
| * Layout during a scroll that results from tracking motion events. Places |
| * the mMotionPosition view at the offset specified by mMotionViewTop, and |
| * then build surrounding views from there. |
| * |
| * @param position the position at which to start filling |
| * @param top the top of the view at that position |
| * @return The selected view, or null if the selected view is outside the |
| * visible area. |
| */ |
| private View fillSpecific(int position, int top) { |
| final int numColumns = mNumColumns; |
| |
| int motionRowStart; |
| int motionRowEnd = -1; |
| |
| if (!mStackFromBottom) { |
| motionRowStart = position - (position % numColumns); |
| } else { |
| final int invertedSelection = mItemCount - 1 - position; |
| |
| motionRowEnd = mItemCount - 1 - (invertedSelection - (invertedSelection % numColumns)); |
| motionRowStart = Math.max(0, motionRowEnd - numColumns + 1); |
| } |
| |
| final View temp = makeRow(mStackFromBottom ? motionRowEnd : motionRowStart, top, true); |
| |
| // Possibly changed again in fillUp if we add rows above this one. |
| mFirstPosition = motionRowStart; |
| |
| final View referenceView = mReferenceView; |
| // We didn't have anything to layout, bail out |
| if (referenceView == null) { |
| return null; |
| } |
| |
| final int verticalSpacing = mVerticalSpacing; |
| |
| View above; |
| View below; |
| |
| if (!mStackFromBottom) { |
| above = fillUp(motionRowStart - numColumns, referenceView.getTop() - verticalSpacing); |
| adjustViewsUpOrDown(); |
| below = fillDown(motionRowStart + numColumns, referenceView.getBottom() + verticalSpacing); |
| // Check if we have dragged the bottom of the grid too high |
| final int childCount = getChildCount(); |
| if (childCount > 0) { |
| correctTooHigh(numColumns, verticalSpacing, childCount); |
| } |
| } else { |
| below = fillDown(motionRowEnd + numColumns, referenceView.getBottom() + verticalSpacing); |
| adjustViewsUpOrDown(); |
| above = fillUp(motionRowStart - 1, referenceView.getTop() - verticalSpacing); |
| // Check if we have dragged the bottom of the grid too high |
| final int childCount = getChildCount(); |
| if (childCount > 0) { |
| correctTooLow(numColumns, verticalSpacing, childCount); |
| } |
| } |
| |
| if (temp != null) { |
| return temp; |
| } else if (above != null) { |
| return above; |
| } else { |
| return below; |
| } |
| } |
| |
| private void correctTooHigh(int numColumns, int verticalSpacing, int childCount) { |
| // First see if the last item is visible |
| final int lastPosition = mFirstPosition + childCount - 1; |
| if (lastPosition == mItemCount - 1 && childCount > 0) { |
| // Get the last child ... |
| final View lastChild = getChildAt(childCount - 1); |
| |
| // ... and its bottom edge |
| final int lastBottom = lastChild.getBottom(); |
| // This is bottom of our drawable area |
| final int end = (mBottom - mTop) - mListPadding.bottom; |
| |
| // This is how far the bottom edge of the last view is from the bottom of the |
| // drawable area |
| int bottomOffset = end - lastBottom; |
| |
| final View firstChild = getChildAt(0); |
| final int firstTop = firstChild.getTop(); |
| |
| // Make sure we are 1) Too high, and 2) Either there are more rows above the |
| // first row or the first row is scrolled off the top of the drawable area |
| if (bottomOffset > 0 && (mFirstPosition > 0 || firstTop < mListPadding.top)) { |
| if (mFirstPosition == 0) { |
| // Don't pull the top too far down |
| bottomOffset = Math.min(bottomOffset, mListPadding.top - firstTop); |
| } |
| |
| // Move everything down |
| offsetChildrenTopAndBottom(bottomOffset); |
| if (mFirstPosition > 0) { |
| // Fill the gap that was opened above mFirstPosition with more rows, if |
| // possible |
| fillUp(mFirstPosition - (mStackFromBottom ? 1 : numColumns), |
| firstChild.getTop() - verticalSpacing); |
| // Close up the remaining gap |
| adjustViewsUpOrDown(); |
| } |
| } |
| } |
| } |
| |
| private void correctTooLow(int numColumns, int verticalSpacing, int childCount) { |
| if (mFirstPosition == 0 && childCount > 0) { |
| // Get the first child ... |
| final View firstChild = getChildAt(0); |
| |
| // ... and its top edge |
| final int firstTop = firstChild.getTop(); |
| |
| // This is top of our drawable area |
| final int start = mListPadding.top; |
| |
| // This is bottom of our drawable area |
| final int end = (mBottom - mTop) - mListPadding.bottom; |
| |
| // This is how far the top edge of the first view is from the top of the |
| // drawable area |
| int topOffset = firstTop - start; |
| final View lastChild = getChildAt(childCount - 1); |
| final int lastBottom = lastChild.getBottom(); |
| final int lastPosition = mFirstPosition + childCount - 1; |
| |
| // Make sure we are 1) Too low, and 2) Either there are more rows below the |
| // last row or the last row is scrolled off the bottom of the drawable area |
| if (topOffset > 0 && (lastPosition < mItemCount - 1 || lastBottom > end)) { |
| if (lastPosition == mItemCount - 1 ) { |
| // Don't pull the bottom too far up |
| topOffset = Math.min(topOffset, lastBottom - end); |
| } |
| |
| // Move everything up |
| offsetChildrenTopAndBottom(-topOffset); |
| if (lastPosition < mItemCount - 1) { |
| // Fill the gap that was opened below the last position with more rows, if |
| // possible |
| fillDown(lastPosition + (!mStackFromBottom ? 1 : numColumns), |
| lastChild.getBottom() + verticalSpacing); |
| // Close up the remaining gap |
| adjustViewsUpOrDown(); |
| } |
| } |
| } |
| } |
| |
| /** |
| * Fills the grid based on positioning the new selection at a specific |
| * location. The selection may be moved so that it does not intersect the |
| * faded edges. The grid is then filled upwards and downwards from there. |
| * |
| * @param selectedTop Where the selected item should be |
| * @param childrenTop Where to start drawing children |
| * @param childrenBottom Last pixel where children can be drawn |
| * @return The view that currently has selection |
| */ |
| private View fillFromSelection(int selectedTop, int childrenTop, int childrenBottom) { |
| final int fadingEdgeLength = getVerticalFadingEdgeLength(); |
| final int selectedPosition = mSelectedPosition; |
| final int numColumns = mNumColumns; |
| final int verticalSpacing = mVerticalSpacing; |
| |
| int rowStart; |
| int rowEnd = -1; |
| |
| if (!mStackFromBottom) { |
| rowStart = selectedPosition - (selectedPosition % numColumns); |
| } else { |
| int invertedSelection = mItemCount - 1 - selectedPosition; |
| |
| rowEnd = mItemCount - 1 - (invertedSelection - (invertedSelection % numColumns)); |
| rowStart = Math.max(0, rowEnd - numColumns + 1); |
| } |
| |
| View sel; |
| View referenceView; |
| |
| int topSelectionPixel = getTopSelectionPixel(childrenTop, fadingEdgeLength, rowStart); |
| int bottomSelectionPixel = getBottomSelectionPixel(childrenBottom, fadingEdgeLength, |
| numColumns, rowStart); |
| |
| sel = makeRow(mStackFromBottom ? rowEnd : rowStart, selectedTop, true); |
| // Possibly changed again in fillUp if we add rows above this one. |
| mFirstPosition = rowStart; |
| |
| referenceView = mReferenceView; |
| adjustForTopFadingEdge(referenceView, topSelectionPixel, bottomSelectionPixel); |
| adjustForBottomFadingEdge(referenceView, topSelectionPixel, bottomSelectionPixel); |
| |
| if (!mStackFromBottom) { |
| fillUp(rowStart - numColumns, referenceView.getTop() - verticalSpacing); |
| adjustViewsUpOrDown(); |
| fillDown(rowStart + numColumns, referenceView.getBottom() + verticalSpacing); |
| } else { |
| fillDown(rowEnd + numColumns, referenceView.getBottom() + verticalSpacing); |
| adjustViewsUpOrDown(); |
| fillUp(rowStart - 1, referenceView.getTop() - verticalSpacing); |
| } |
| |
| |
| return sel; |
| } |
| |
| /** |
| * Calculate the bottom-most pixel we can draw the selection into |
| * |
| * @param childrenBottom Bottom pixel were children can be drawn |
| * @param fadingEdgeLength Length of the fading edge in pixels, if present |
| * @param numColumns Number of columns in the grid |
| * @param rowStart The start of the row that will contain the selection |
| * @return The bottom-most pixel we can draw the selection into |
| */ |
| private int getBottomSelectionPixel(int childrenBottom, int fadingEdgeLength, |
| int numColumns, int rowStart) { |
| // Last pixel we can draw the selection into |
| int bottomSelectionPixel = childrenBottom; |
| if (rowStart + numColumns - 1 < mItemCount - 1) { |
| bottomSelectionPixel -= fadingEdgeLength; |
| } |
| return bottomSelectionPixel; |
| } |
| |
| /** |
| * Calculate the top-most pixel we can draw the selection into |
| * |
| * @param childrenTop Top pixel were children can be drawn |
| * @param fadingEdgeLength Length of the fading edge in pixels, if present |
| * @param rowStart The start of the row that will contain the selection |
| * @return The top-most pixel we can draw the selection into |
| */ |
| private int getTopSelectionPixel(int childrenTop, int fadingEdgeLength, int rowStart) { |
| // first pixel we can draw the selection into |
| int topSelectionPixel = childrenTop; |
| if (rowStart > 0) { |
| topSelectionPixel += fadingEdgeLength; |
| } |
| return topSelectionPixel; |
| } |
| |
| /** |
| * Move all views upwards so the selected row does not interesect the bottom |
| * fading edge (if necessary). |
| * |
| * @param childInSelectedRow A child in the row that contains the selection |
| * @param topSelectionPixel The topmost pixel we can draw the selection into |
| * @param bottomSelectionPixel The bottommost pixel we can draw the |
| * selection into |
| */ |
| private void adjustForBottomFadingEdge(View childInSelectedRow, |
| int topSelectionPixel, int bottomSelectionPixel) { |
| // Some of the newly selected item extends below the bottom of the |
| // list |
| if (childInSelectedRow.getBottom() > bottomSelectionPixel) { |
| |
| // Find space available above the selection into which we can |
| // scroll upwards |
| int spaceAbove = childInSelectedRow.getTop() - topSelectionPixel; |
| |
| // Find space required to bring the bottom of the selected item |
| // fully into view |
| int spaceBelow = childInSelectedRow.getBottom() - bottomSelectionPixel; |
| int offset = Math.min(spaceAbove, spaceBelow); |
| |
| // Now offset the selected item to get it into view |
| offsetChildrenTopAndBottom(-offset); |
| } |
| } |
| |
| /** |
| * Move all views upwards so the selected row does not interesect the top |
| * fading edge (if necessary). |
| * |
| * @param childInSelectedRow A child in the row that contains the selection |
| * @param topSelectionPixel The topmost pixel we can draw the selection into |
| * @param bottomSelectionPixel The bottommost pixel we can draw the |
| * selection into |
| */ |
| private void adjustForTopFadingEdge(View childInSelectedRow, |
| int topSelectionPixel, int bottomSelectionPixel) { |
| // Some of the newly selected item extends above the top of the list |
| if (childInSelectedRow.getTop() < topSelectionPixel) { |
| // Find space required to bring the top of the selected item |
| // fully into view |
| int spaceAbove = topSelectionPixel - childInSelectedRow.getTop(); |
| |
| // Find space available below the selection into which we can |
| // scroll downwards |
| int spaceBelow = bottomSelectionPixel - childInSelectedRow.getBottom(); |
| int offset = Math.min(spaceAbove, spaceBelow); |
| |
| // Now offset the selected item to get it into view |
| offsetChildrenTopAndBottom(offset); |
| } |
| } |
| |
| /** |
| * Smoothly scroll to the specified adapter position. The view will |
| * scroll such that the indicated position is displayed. |
| * @param position Scroll to this adapter position. |
| */ |
| @android.view.RemotableViewMethod |
| public void smoothScrollToPosition(int position) { |
| super.smoothScrollToPosition(position); |
| } |
| |
| /** |
| * Smoothly scroll to the specified adapter position offset. The view will |
| * scroll such that the indicated position is displayed. |
| * @param offset The amount to offset from the adapter position to scroll to. |
| */ |
| @android.view.RemotableViewMethod |
| public void smoothScrollByOffset(int offset) { |
| super.smoothScrollByOffset(offset); |
| } |
| |
| /** |
| * Fills the grid based on positioning the new selection relative to the old |
| * selection. The new selection will be placed at, above, or below the |
| * location of the new selection depending on how the selection is moving. |
| * The selection will then be pinned to the visible part of the screen, |
| * excluding the edges that are faded. The grid is then filled upwards and |
| * downwards from there. |
| * |
| * @param delta Which way we are moving |
| * @param childrenTop Where to start drawing children |
| * @param childrenBottom Last pixel where children can be drawn |
| * @return The view that currently has selection |
| */ |
| private View moveSelection(int delta, int childrenTop, int childrenBottom) { |
| final int fadingEdgeLength = getVerticalFadingEdgeLength(); |
| final int selectedPosition = mSelectedPosition; |
| final int numColumns = mNumColumns; |
| final int verticalSpacing = mVerticalSpacing; |
| |
| int oldRowStart; |
| int rowStart; |
| int rowEnd = -1; |
| |
| if (!mStackFromBottom) { |
| oldRowStart = (selectedPosition - delta) - ((selectedPosition - delta) % numColumns); |
| |
| rowStart = selectedPosition - (selectedPosition % numColumns); |
| } else { |
| int invertedSelection = mItemCount - 1 - selectedPosition; |
| |
| rowEnd = mItemCount - 1 - (invertedSelection - (invertedSelection % numColumns)); |
| rowStart = Math.max(0, rowEnd - numColumns + 1); |
| |
| invertedSelection = mItemCount - 1 - (selectedPosition - delta); |
| oldRowStart = mItemCount - 1 - (invertedSelection - (invertedSelection % numColumns)); |
| oldRowStart = Math.max(0, oldRowStart - numColumns + 1); |
| } |
| |
| final int rowDelta = rowStart - oldRowStart; |
| |
| final int topSelectionPixel = getTopSelectionPixel(childrenTop, fadingEdgeLength, rowStart); |
| final int bottomSelectionPixel = getBottomSelectionPixel(childrenBottom, fadingEdgeLength, |
| numColumns, rowStart); |
| |
| // Possibly changed again in fillUp if we add rows above this one. |
| mFirstPosition = rowStart; |
| |
| View sel; |
| View referenceView; |
| |
| if (rowDelta > 0) { |
| /* |
| * Case 1: Scrolling down. |
| */ |
| |
| final int oldBottom = mReferenceViewInSelectedRow == null ? 0 : |
| mReferenceViewInSelectedRow.getBottom(); |
| |
| sel = makeRow(mStackFromBottom ? rowEnd : rowStart, oldBottom + verticalSpacing, true); |
| referenceView = mReferenceView; |
| |
| adjustForBottomFadingEdge(referenceView, topSelectionPixel, bottomSelectionPixel); |
| } else if (rowDelta < 0) { |
| /* |
| * Case 2: Scrolling up. |
| */ |
| final int oldTop = mReferenceViewInSelectedRow == null ? |
| 0 : mReferenceViewInSelectedRow .getTop(); |
| |
| sel = makeRow(mStackFromBottom ? rowEnd : rowStart, oldTop - verticalSpacing, false); |
| referenceView = mReferenceView; |
| |
| adjustForTopFadingEdge(referenceView, topSelectionPixel, bottomSelectionPixel); |
| } else { |
| /* |
| * Keep selection where it was |
| */ |
| final int oldTop = mReferenceViewInSelectedRow == null ? |
| 0 : mReferenceViewInSelectedRow .getTop(); |
| |
| sel = makeRow(mStackFromBottom ? rowEnd : rowStart, oldTop, true); |
| referenceView = mReferenceView; |
| } |
| |
| if (!mStackFromBottom) { |
| fillUp(rowStart - numColumns, referenceView.getTop() - verticalSpacing); |
| adjustViewsUpOrDown(); |
| fillDown(rowStart + numColumns, referenceView.getBottom() + verticalSpacing); |
| } else { |
| fillDown(rowEnd + numColumns, referenceView.getBottom() + verticalSpacing); |
| adjustViewsUpOrDown(); |
| fillUp(rowStart - 1, referenceView.getTop() - verticalSpacing); |
| } |
| |
| return sel; |
| } |
| |
| private boolean determineColumns(int availableSpace) { |
| final int requestedHorizontalSpacing = mRequestedHorizontalSpacing; |
| final int stretchMode = mStretchMode; |
| final int requestedColumnWidth = mRequestedColumnWidth; |
| boolean didNotInitiallyFit = false; |
| |
| if (mRequestedNumColumns == AUTO_FIT) { |
| if (requestedColumnWidth > 0) { |
| // Client told us to pick the number of columns |
| mNumColumns = (availableSpace + requestedHorizontalSpacing) / |
| (requestedColumnWidth + requestedHorizontalSpacing); |
| } else { |
| // Just make up a number if we don't have enough info |
| mNumColumns = 2; |
| } |
| } else { |
| // We picked the columns |
| mNumColumns = mRequestedNumColumns; |
| } |
| |
| if (mNumColumns <= 0) { |
| mNumColumns = 1; |
| } |
| |
| switch (stretchMode) { |
| case NO_STRETCH: |
| // Nobody stretches |
| mColumnWidth = requestedColumnWidth; |
| mHorizontalSpacing = requestedHorizontalSpacing; |
| break; |
| |
| default: |
| int spaceLeftOver = availableSpace - (mNumColumns * requestedColumnWidth) - |
| ((mNumColumns - 1) * requestedHorizontalSpacing); |
| |
| if (spaceLeftOver < 0) { |
| didNotInitiallyFit = true; |
| } |
| |
| switch (stretchMode) { |
| case STRETCH_COLUMN_WIDTH: |
| // Stretch the columns |
| mColumnWidth = requestedColumnWidth + spaceLeftOver / mNumColumns; |
| mHorizontalSpacing = requestedHorizontalSpacing; |
| break; |
| |
| case STRETCH_SPACING: |
| // Stretch the spacing between columns |
| mColumnWidth = requestedColumnWidth; |
| if (mNumColumns > 1) { |
| mHorizontalSpacing = requestedHorizontalSpacing + |
| spaceLeftOver / (mNumColumns - 1); |
| } else { |
| mHorizontalSpacing = requestedHorizontalSpacing + spaceLeftOver; |
| } |
| break; |
| |
| case STRETCH_SPACING_UNIFORM: |
| // Stretch the spacing between columns |
| mColumnWidth = requestedColumnWidth; |
| if (mNumColumns > 1) { |
| mHorizontalSpacing = requestedHorizontalSpacing + |
| spaceLeftOver / (mNumColumns + 1); |
| } else { |
| mHorizontalSpacing = requestedHorizontalSpacing + spaceLeftOver; |
| } |
| break; |
| } |
| |
| break; |
| } |
| return didNotInitiallyFit; |
| } |
| |
| @Override |
| protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { |
| // Sets up mListPadding |
| super.onMeasure(widthMeasureSpec, heightMeasureSpec); |
| |
| int widthMode = MeasureSpec.getMode(widthMeasureSpec); |
| int heightMode = MeasureSpec.getMode(heightMeasureSpec); |
| int widthSize = MeasureSpec.getSize(widthMeasureSpec); |
| int heightSize = MeasureSpec.getSize(heightMeasureSpec); |
| |
| if (widthMode == MeasureSpec.UNSPECIFIED) { |
| if (mColumnWidth > 0) { |
| widthSize = mColumnWidth + mListPadding.left + mListPadding.right; |
| } else { |
| widthSize = mListPadding.left + mListPadding.right; |
| } |
| widthSize += getVerticalScrollbarWidth(); |
| } |
| |
| int childWidth = widthSize - mListPadding.left - mListPadding.right; |
| boolean didNotInitiallyFit = determineColumns(childWidth); |
| |
| int childHeight = 0; |
| int childState = 0; |
| |
| mItemCount = mAdapter == null ? 0 : mAdapter.getCount(); |
| final int count = mItemCount; |
| if (count > 0) { |
| final View child = obtainView(0, mIsScrap); |
| |
| AbsListView.LayoutParams p = (AbsListView.LayoutParams) child.getLayoutParams(); |
| if (p == null) { |
| p = (AbsListView.LayoutParams) generateDefaultLayoutParams(); |
| child.setLayoutParams(p); |
| } |
| p.viewType = mAdapter.getItemViewType(0); |
| p.forceAdd = true; |
| |
| int childHeightSpec = getChildMeasureSpec( |
| MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 0, p.height); |
| int childWidthSpec = getChildMeasureSpec( |
| MeasureSpec.makeMeasureSpec(mColumnWidth, MeasureSpec.EXACTLY), 0, p.width); |
| child.measure(childWidthSpec, childHeightSpec); |
| |
| childHeight = child.getMeasuredHeight(); |
| childState = combineMeasuredStates(childState, child.getMeasuredState()); |
| |
| if (mRecycler.shouldRecycleViewType(p.viewType)) { |
| mRecycler.addScrapView(child, -1); |
| } |
| } |
| |
| if (heightMode == MeasureSpec.UNSPECIFIED) { |
| heightSize = mListPadding.top + mListPadding.bottom + childHeight + |
| getVerticalFadingEdgeLength() * 2; |
| } |
| |
| if (heightMode == MeasureSpec.AT_MOST) { |
| int ourSize = mListPadding.top + mListPadding.bottom; |
| |
| final int numColumns = mNumColumns; |
| for (int i = 0; i < count; i += numColumns) { |
| ourSize += childHeight; |
| if (i + numColumns < count) { |
| ourSize += mVerticalSpacing; |
| } |
| if (ourSize >= heightSize) { |
| ourSize = heightSize; |
| break; |
| } |
| } |
| heightSize = ourSize; |
| } |
| |
| if (widthMode == MeasureSpec.AT_MOST && mRequestedNumColumns != AUTO_FIT) { |
| int ourSize = (mRequestedNumColumns*mColumnWidth) |
| + ((mRequestedNumColumns-1)*mHorizontalSpacing) |
| + mListPadding.left + mListPadding.right; |
| if (ourSize > widthSize || didNotInitiallyFit) { |
| widthSize |= MEASURED_STATE_TOO_SMALL; |
| } |
| } |
| |
| setMeasuredDimension(widthSize, heightSize); |
| mWidthMeasureSpec = widthMeasureSpec; |
| } |
| |
| @Override |
| protected void attachLayoutAnimationParameters(View child, |
| ViewGroup.LayoutParams params, int index, int count) { |
| |
| GridLayoutAnimationController.AnimationParameters animationParams = |
| (GridLayoutAnimationController.AnimationParameters) params.layoutAnimationParameters; |
| |
| if (animationParams == null) { |
| animationParams = new GridLayoutAnimationController.AnimationParameters(); |
| params.layoutAnimationParameters = animationParams; |
| } |
| |
| animationParams.count = count; |
| animationParams.index = index; |
| animationParams.columnsCount = mNumColumns; |
| animationParams.rowsCount = count / mNumColumns; |
| |
| if (!mStackFromBottom) { |
| animationParams.column = index % mNumColumns; |
| animationParams.row = index / mNumColumns; |
| } else { |
| final int invertedIndex = count - 1 - index; |
| |
| animationParams.column = mNumColumns - 1 - (invertedIndex % mNumColumns); |
| animationParams.row = animationParams.rowsCount - 1 - invertedIndex / mNumColumns; |
| } |
| } |
| |
| @Override |
| protected void layoutChildren() { |
| final boolean blockLayoutRequests = mBlockLayoutRequests; |
| if (!blockLayoutRequests) { |
| mBlockLayoutRequests = true; |
| } |
| |
| try { |
| super.layoutChildren(); |
| |
| invalidate(); |
| |
| if (mAdapter == null) { |
| resetList(); |
| invokeOnItemScrollListener(); |
| return; |
| } |
| |
| final int childrenTop = mListPadding.top; |
| final int childrenBottom = mBottom - mTop - mListPadding.bottom; |
| |
| int childCount = getChildCount(); |
| int index; |
| int delta = 0; |
| |
| View sel; |
| View oldSel = null; |
| View oldFirst = null; |
| View newSel = null; |
| |
| // Remember stuff we will need down below |
| switch (mLayoutMode) { |
| case LAYOUT_SET_SELECTION: |
| index = mNextSelectedPosition - mFirstPosition; |
| if (index >= 0 && index < childCount) { |
| newSel = getChildAt(index); |
| } |
| break; |
| case LAYOUT_FORCE_TOP: |
| case LAYOUT_FORCE_BOTTOM: |
| case LAYOUT_SPECIFIC: |
| case LAYOUT_SYNC: |
| break; |
| case LAYOUT_MOVE_SELECTION: |
| if (mNextSelectedPosition >= 0) { |
| delta = mNextSelectedPosition - mSelectedPosition; |
| } |
| break; |
| default: |
| // Remember the previously selected view |
| index = mSelectedPosition - mFirstPosition; |
| if (index >= 0 && index < childCount) { |
| oldSel = getChildAt(index); |
| } |
| |
| // Remember the previous first child |
| oldFirst = getChildAt(0); |
| } |
| |
| boolean dataChanged = mDataChanged; |
| if (dataChanged) { |
| handleDataChanged(); |
| } |
| |
| // Handle the empty set by removing all views that are visible |
| // and calling it a day |
| if (mItemCount == 0) { |
| resetList(); |
| invokeOnItemScrollListener(); |
| return; |
| } |
| |
| setSelectedPositionInt(mNextSelectedPosition); |
| |
| // Pull all children into the RecycleBin. |
| // These views will be reused if possible |
| final int firstPosition = mFirstPosition; |
| final RecycleBin recycleBin = mRecycler; |
| |
| if (dataChanged) { |
| for (int i = 0; i < childCount; i++) { |
| recycleBin.addScrapView(getChildAt(i), firstPosition+i); |
| } |
| } else { |
| recycleBin.fillActiveViews(childCount, firstPosition); |
| } |
| |
| // Clear out old views |
| //removeAllViewsInLayout(); |
| detachAllViewsFromParent(); |
| recycleBin.removeSkippedScrap(); |
| |
| switch (mLayoutMode) { |
| case LAYOUT_SET_SELECTION: |
| if (newSel != null) { |
| sel = fillFromSelection(newSel.getTop(), childrenTop, childrenBottom); |
| } else { |
| sel = fillSelection(childrenTop, childrenBottom); |
| } |
| break; |
| case LAYOUT_FORCE_TOP: |
| mFirstPosition = 0; |
| sel = fillFromTop(childrenTop); |
| adjustViewsUpOrDown(); |
| break; |
| case LAYOUT_FORCE_BOTTOM: |
| sel = fillUp(mItemCount - 1, childrenBottom); |
| adjustViewsUpOrDown(); |
| break; |
| case LAYOUT_SPECIFIC: |
| sel = fillSpecific(mSelectedPosition, mSpecificTop); |
| break; |
| case LAYOUT_SYNC: |
| sel = fillSpecific(mSyncPosition, mSpecificTop); |
| break; |
| case LAYOUT_MOVE_SELECTION: |
| // Move the selection relative to its old position |
| sel = moveSelection(delta, childrenTop, childrenBottom); |
| break; |
| default: |
| if (childCount == 0) { |
| if (!mStackFromBottom) { |
| setSelectedPositionInt(mAdapter == null || isInTouchMode() ? |
| INVALID_POSITION : 0); |
| sel = fillFromTop(childrenTop); |
| } else { |
| final int last = mItemCount - 1; |
| setSelectedPositionInt(mAdapter == null || isInTouchMode() ? |
| INVALID_POSITION : last); |
| sel = fillFromBottom(last, childrenBottom); |
| } |
| } else { |
| if (mSelectedPosition >= 0 && mSelectedPosition < mItemCount) { |
| sel = fillSpecific(mSelectedPosition, oldSel == null ? |
| childrenTop : oldSel.getTop()); |
| } else if (mFirstPosition < mItemCount) { |
| sel = fillSpecific(mFirstPosition, oldFirst == null ? |
| childrenTop : oldFirst.getTop()); |
| } else { |
| sel = fillSpecific(0, childrenTop); |
| } |
| } |
| break; |
| } |
| |
| // Flush any cached views that did not get reused above |
| recycleBin.scrapActiveViews(); |
| |
| if (sel != null) { |
| positionSelector(INVALID_POSITION, sel); |
| mSelectedTop = sel.getTop(); |
| } else if (mTouchMode > TOUCH_MODE_DOWN && mTouchMode < TOUCH_MODE_SCROLL) { |
| View child = getChildAt(mMotionPosition - mFirstPosition); |
| if (child != null) positionSelector(mMotionPosition, child); |
| } else { |
| mSelectedTop = 0; |
| mSelectorRect.setEmpty(); |
| } |
| |
| mLayoutMode = LAYOUT_NORMAL; |
| mDataChanged = false; |
| if (mPositionScrollAfterLayout != null) { |
| post(mPositionScrollAfterLayout); |
| mPositionScrollAfterLayout = null; |
| } |
| mNeedSync = false; |
| setNextSelectedPositionInt(mSelectedPosition); |
| |
| updateScrollIndicators(); |
| |
| if (mItemCount > 0) { |
| checkSelectionChanged(); |
| } |
| |
| invokeOnItemScrollListener(); |
| } finally { |
| if (!blockLayoutRequests) { |
| mBlockLayoutRequests = false; |
| } |
| } |
| } |
| |
| |
| /** |
| * Obtain the view and add it to our list of children. The view can be made |
| * fresh, converted from an unused view, or used as is if it was in the |
| * recycle bin. |
| * |
| * @param position Logical position in the list |
| * @param y Top or bottom edge of the view to add |
| * @param flow if true, align top edge to y. If false, align bottom edge to |
| * y. |
| * @param childrenLeft Left edge where children should be positioned |
| * @param selected Is this position selected? |
| * @param where to add new item in the list |
| * @return View that was added |
| */ |
| private View makeAndAddView(int position, int y, boolean flow, int childrenLeft, |
| boolean selected, int where) { |
| View child; |
| |
| if (!mDataChanged) { |
| // Try to use an existing view for this position |
| child = mRecycler.getActiveView(position); |
| if (child != null) { |
| // Found it -- we're using an existing child |
| // This just needs to be positioned |
| setupChild(child, position, y, flow, childrenLeft, selected, true, where); |
| return child; |
| } |
| } |
| |
| // Make a new view for this position, or convert an unused view if |
| // possible |
| child = obtainView(position, mIsScrap); |
| |
| // This needs to be positioned and measured |
| setupChild(child, position, y, flow, childrenLeft, selected, mIsScrap[0], where); |
| |
| return child; |
| } |
| |
| /** |
| * Add a view as a child and make sure it is measured (if necessary) and |
| * positioned properly. |
| * |
| * @param child The view to add |
| * @param position The position of the view |
| * @param y The y position relative to which this view will be positioned |
| * @param flow if true, align top edge to y. If false, align bottom edge |
| * to y. |
| * @param childrenLeft Left edge where children should be positioned |
| * @param selected Is this position selected? |
| * @param recycled Has this view been pulled from the recycle bin? If so it |
| * does not need to be remeasured. |
| * @param where Where to add the item in the list |
| * |
| */ |
| private void setupChild(View child, int position, int y, boolean flow, int childrenLeft, |
| boolean selected, boolean recycled, int where) { |
| boolean isSelected = selected && shouldShowSelector(); |
| final boolean updateChildSelected = isSelected != child.isSelected(); |
| final int mode = mTouchMode; |
| final boolean isPressed = mode > TOUCH_MODE_DOWN && mode < TOUCH_MODE_SCROLL && |
| mMotionPosition == position; |
| final boolean updateChildPressed = isPressed != child.isPressed(); |
| |
| boolean needToMeasure = !recycled || updateChildSelected || child.isLayoutRequested(); |
| |
| // Respect layout params that are already in the view. Otherwise make |
| // some up... |
| AbsListView.LayoutParams p = (AbsListView.LayoutParams) child.getLayoutParams(); |
| if (p == null) { |
| p = (AbsListView.LayoutParams) generateDefaultLayoutParams(); |
| } |
| p.viewType = mAdapter.getItemViewType(position); |
| |
| if (recycled && !p.forceAdd) { |
| attachViewToParent(child, where, p); |
| } else { |
| p.forceAdd = false; |
| addViewInLayout(child, where, p, true); |
| } |
| |
| if (updateChildSelected) { |
| child.setSelected(isSelected); |
| if (isSelected) { |
| requestFocus(); |
| } |
| } |
| |
| if (updateChildPressed) { |
| child.setPressed(isPressed); |
| } |
| |
| if (mChoiceMode != CHOICE_MODE_NONE && mCheckStates != null) { |
| if (child instanceof Checkable) { |
| ((Checkable) child).setChecked(mCheckStates.get(position)); |
| } else if (getContext().getApplicationInfo().targetSdkVersion |
| >= android.os.Build.VERSION_CODES.HONEYCOMB) { |
| child.setActivated(mCheckStates.get(position)); |
| } |
| } |
| |
| if (needToMeasure) { |
| int childHeightSpec = ViewGroup.getChildMeasureSpec( |
| MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 0, p.height); |
| |
| int childWidthSpec = ViewGroup.getChildMeasureSpec( |
| MeasureSpec.makeMeasureSpec(mColumnWidth, MeasureSpec.EXACTLY), 0, p.width); |
| child.measure(childWidthSpec, childHeightSpec); |
| } else { |
| cleanupLayoutState(child); |
| } |
| |
| final int w = child.getMeasuredWidth(); |
| final int h = child.getMeasuredHeight(); |
| |
| int childLeft; |
| final int childTop = flow ? y : y - h; |
| |
| final int layoutDirection = getLayoutDirection(); |
| final int absoluteGravity = Gravity.getAbsoluteGravity(mGravity, layoutDirection); |
| switch (absoluteGravity & Gravity.HORIZONTAL_GRAVITY_MASK) { |
| case Gravity.LEFT: |
| childLeft = childrenLeft; |
| break; |
| case Gravity.CENTER_HORIZONTAL: |
| childLeft = childrenLeft + ((mColumnWidth - w) / 2); |
| break; |
| case Gravity.RIGHT: |
| childLeft = childrenLeft + mColumnWidth - w; |
| break; |
| default: |
| childLeft = childrenLeft; |
| break; |
| } |
| |
| if (needToMeasure) { |
| final int childRight = childLeft + w; |
| final int childBottom = childTop + h; |
| child.layout(childLeft, childTop, childRight, childBottom); |
| } else { |
| child.offsetLeftAndRight(childLeft - child.getLeft()); |
| child.offsetTopAndBottom(childTop - child.getTop()); |
| } |
| |
| if (mCachingStarted) { |
| child.setDrawingCacheEnabled(true); |
| } |
| |
| if (recycled && (((AbsListView.LayoutParams)child.getLayoutParams()).scrappedFromPosition) |
| != position) { |
| child.jumpDrawablesToCurrentState(); |
| } |
| } |
| |
| /** |
| * Sets the currently selected item |
| * |
| * @param position Index (starting at 0) of the data item to be selected. |
| * |
| * If in touch mode, the item will not be selected but it will still be positioned |
| * appropriately. |
| */ |
| @Override |
| public void setSelection(int position) { |
| if (!isInTouchMode()) { |
| setNextSelectedPositionInt(position); |
| } else { |
| mResurrectToPosition = position; |
| } |
| mLayoutMode = LAYOUT_SET_SELECTION; |
| if (mPositionScroller != null) { |
| mPositionScroller.stop(); |
| } |
| requestLayout(); |
| } |
| |
| /** |
| * Makes the item at the supplied position selected. |
| * |
| * @param position the position of the new selection |
| */ |
| @Override |
| void setSelectionInt(int position) { |
| int previousSelectedPosition = mNextSelectedPosition; |
| |
| if (mPositionScroller != null) { |
| mPositionScroller.stop(); |
| } |
| |
| setNextSelectedPositionInt(position); |
| layoutChildren(); |
| |
| final int next = mStackFromBottom ? mItemCount - 1 - mNextSelectedPosition : |
| mNextSelectedPosition; |
| final int previous = mStackFromBottom ? mItemCount - 1 |
| - previousSelectedPosition : previousSelectedPosition; |
| |
| final int nextRow = next / mNumColumns; |
| final int previousRow = previous / mNumColumns; |
| |
| if (nextRow != previousRow) { |
| awakenScrollBars(); |
| } |
| |
| } |
| |
| @Override |
| public boolean onKeyDown(int keyCode, KeyEvent event) { |
| return commonKey(keyCode, 1, event); |
| } |
| |
| @Override |
| public boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent event) { |
| return commonKey(keyCode, repeatCount, event); |
| } |
| |
| @Override |
| public boolean onKeyUp(int keyCode, KeyEvent event) { |
| return commonKey(keyCode, 1, event); |
| } |
| |
| private boolean commonKey(int keyCode, int count, KeyEvent event) { |
| if (mAdapter == null) { |
| return false; |
| } |
| |
| if (mDataChanged) { |
| layoutChildren(); |
| } |
| |
| boolean handled = false; |
| int action = event.getAction(); |
| |
| if (action != KeyEvent.ACTION_UP) { |
| switch (keyCode) { |
| case KeyEvent.KEYCODE_DPAD_LEFT: |
| if (event.hasNoModifiers()) { |
| handled = resurrectSelectionIfNeeded() || arrowScroll(FOCUS_LEFT); |
| } |
| break; |
| |
| case KeyEvent.KEYCODE_DPAD_RIGHT: |
| if (event.hasNoModifiers()) { |
| handled = resurrectSelectionIfNeeded() || arrowScroll(FOCUS_RIGHT); |
| } |
| break; |
| |
| case KeyEvent.KEYCODE_DPAD_UP: |
| if (event.hasNoModifiers()) { |
| handled = resurrectSelectionIfNeeded() || arrowScroll(FOCUS_UP); |
| } else if (event.hasModifiers(KeyEvent.META_ALT_ON)) { |
| handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_UP); |
| } |
| break; |
| |
| case KeyEvent.KEYCODE_DPAD_DOWN: |
| if (event.hasNoModifiers()) { |
| handled = resurrectSelectionIfNeeded() || arrowScroll(FOCUS_DOWN); |
| } else if (event.hasModifiers(KeyEvent.META_ALT_ON)) { |
| handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_DOWN); |
| } |
| break; |
| |
| case KeyEvent.KEYCODE_DPAD_CENTER: |
| case KeyEvent.KEYCODE_ENTER: |
| if (event.hasNoModifiers()) { |
| handled = resurrectSelectionIfNeeded(); |
| if (!handled |
| && event.getRepeatCount() == 0 && getChildCount() > 0) { |
| keyPressed(); |
| handled = true; |
| } |
| } |
| break; |
| |
| case KeyEvent.KEYCODE_SPACE: |
| if (mPopup == null || !mPopup.isShowing()) { |
| if (event.hasNoModifiers()) { |
| handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_DOWN); |
| } else if (event.hasModifiers(KeyEvent.META_SHIFT_ON)) { |
| handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_UP); |
| } |
| } |
| break; |
| |
| case KeyEvent.KEYCODE_PAGE_UP: |
| if (event.hasNoModifiers()) { |
| handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_UP); |
| } else if (event.hasModifiers(KeyEvent.META_ALT_ON)) { |
| handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_UP); |
| } |
| break; |
| |
| case KeyEvent.KEYCODE_PAGE_DOWN: |
| if (event.hasNoModifiers()) { |
| handled = resurrectSelectionIfNeeded() || pageScroll(FOCUS_DOWN); |
| } else if (event.hasModifiers(KeyEvent.META_ALT_ON)) { |
| handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_DOWN); |
| } |
| break; |
| |
| case KeyEvent.KEYCODE_MOVE_HOME: |
| if (event.hasNoModifiers()) { |
| handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_UP); |
| } |
| break; |
| |
| case KeyEvent.KEYCODE_MOVE_END: |
| if (event.hasNoModifiers()) { |
| handled = resurrectSelectionIfNeeded() || fullScroll(FOCUS_DOWN); |
| } |
| break; |
| |
| case KeyEvent.KEYCODE_TAB: |
| // XXX Sometimes it is useful to be able to TAB through the items in |
| // a GridView sequentially. Unfortunately this can create an |
| // asymmetry in TAB navigation order unless the list selection |
| // always reverts to the top or bottom when receiving TAB focus from |
| // another widget. Leaving this behavior disabled for now but |
| // perhaps it should be configurable (and more comprehensive). |
| if (false) { |
| if (event.hasNoModifiers()) { |
| handled = resurrectSelectionIfNeeded() |
| || sequenceScroll(FOCUS_FORWARD); |
| } else if (event.hasModifiers(KeyEvent.META_SHIFT_ON)) { |
| handled = resurrectSelectionIfNeeded() |
| || sequenceScroll(FOCUS_BACKWARD); |
| } |
| } |
| break; |
| } |
| } |
| |
| if (handled) { |
| return true; |
| } |
| |
| if (sendToTextFilter(keyCode, count, event)) { |
| return true; |
| } |
| |
| switch (action) { |
| case KeyEvent.ACTION_DOWN: |
| return super.onKeyDown(keyCode, event); |
| case KeyEvent.ACTION_UP: |
| return super.onKeyUp(keyCode, event); |
| case KeyEvent.ACTION_MULTIPLE: |
| return super.onKeyMultiple(keyCode, count, event); |
| default: |
| return false; |
| } |
| } |
| |
| /** |
| * Scrolls up or down by the number of items currently present on screen. |
| * |
| * @param direction either {@link View#FOCUS_UP} or {@link View#FOCUS_DOWN} |
| * @return whether selection was moved |
| */ |
| boolean pageScroll(int direction) { |
| int nextPage = -1; |
| |
| if (direction == FOCUS_UP) { |
| nextPage = Math.max(0, mSelectedPosition - getChildCount()); |
| } else if (direction == FOCUS_DOWN) { |
| nextPage = Math.min(mItemCount - 1, mSelectedPosition + getChildCount()); |
| } |
| |
| if (nextPage >= 0) { |
| setSelectionInt(nextPage); |
| invokeOnItemScrollListener(); |
| awakenScrollBars(); |
| return true; |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Go to the last or first item if possible. |
| * |
| * @param direction either {@link View#FOCUS_UP} or {@link View#FOCUS_DOWN}. |
| * |
| * @return Whether selection was moved. |
| */ |
| boolean fullScroll(int direction) { |
| boolean moved = false; |
| if (direction == FOCUS_UP) { |
| mLayoutMode = LAYOUT_SET_SELECTION; |
| setSelectionInt(0); |
| invokeOnItemScrollListener(); |
| moved = true; |
| } else if (direction == FOCUS_DOWN) { |
| mLayoutMode = LAYOUT_SET_SELECTION; |
| setSelectionInt(mItemCount - 1); |
| invokeOnItemScrollListener(); |
| moved = true; |
| } |
| |
| if (moved) { |
| awakenScrollBars(); |
| } |
| |
| return moved; |
| } |
| |
| /** |
| * Scrolls to the next or previous item, horizontally or vertically. |
| * |
| * @param direction either {@link View#FOCUS_LEFT}, {@link View#FOCUS_RIGHT}, |
| * {@link View#FOCUS_UP} or {@link View#FOCUS_DOWN} |
| * |
| * @return whether selection was moved |
| */ |
| boolean arrowScroll(int direction) { |
| final int selectedPosition = mSelectedPosition; |
| final int numColumns = mNumColumns; |
| |
| int startOfRowPos; |
| int endOfRowPos; |
| |
| boolean moved = false; |
| |
| if (!mStackFromBottom) { |
| startOfRowPos = (selectedPosition / numColumns) * numColumns; |
| endOfRowPos = Math.min(startOfRowPos + numColumns - 1, mItemCount - 1); |
| } else { |
| final int invertedSelection = mItemCount - 1 - selectedPosition; |
| endOfRowPos = mItemCount - 1 - (invertedSelection / numColumns) * numColumns; |
| startOfRowPos = Math.max(0, endOfRowPos - numColumns + 1); |
| } |
| |
| switch (direction) { |
| case FOCUS_UP: |
| if (startOfRowPos > 0) { |
| mLayoutMode = LAYOUT_MOVE_SELECTION; |
| setSelectionInt(Math.max(0, selectedPosition - numColumns)); |
| moved = true; |
| } |
| break; |
| case FOCUS_DOWN: |
| if (endOfRowPos < mItemCount - 1) { |
| mLayoutMode = LAYOUT_MOVE_SELECTION; |
| setSelectionInt(Math.min(selectedPosition + numColumns, mItemCount - 1)); |
| moved = true; |
| } |
| break; |
| case FOCUS_LEFT: |
| if (selectedPosition > startOfRowPos) { |
| mLayoutMode = LAYOUT_MOVE_SELECTION; |
| setSelectionInt(Math.max(0, selectedPosition - 1)); |
| moved = true; |
| } |
| break; |
| case FOCUS_RIGHT: |
| if (selectedPosition < endOfRowPos) { |
| mLayoutMode = LAYOUT_MOVE_SELECTION; |
| setSelectionInt(Math.min(selectedPosition + 1, mItemCount - 1)); |
| moved = true; |
| } |
| break; |
| } |
| |
| if (moved) { |
| playSoundEffect(SoundEffectConstants.getContantForFocusDirection(direction)); |
| invokeOnItemScrollListener(); |
| } |
| |
| if (moved) { |
| awakenScrollBars(); |
| } |
| |
| return moved; |
| } |
| |
| /** |
| * Goes to the next or previous item according to the order set by the |
| * adapter. |
| */ |
| boolean sequenceScroll(int direction) { |
| int selectedPosition = mSelectedPosition; |
| int numColumns = mNumColumns; |
| int count = mItemCount; |
| |
| int startOfRow; |
| int endOfRow; |
| if (!mStackFromBottom) { |
| startOfRow = (selectedPosition / numColumns) * numColumns; |
| endOfRow = Math.min(startOfRow + numColumns - 1, count - 1); |
| } else { |
| int invertedSelection = count - 1 - selectedPosition; |
| endOfRow = count - 1 - (invertedSelection / numColumns) * numColumns; |
| startOfRow = Math.max(0, endOfRow - numColumns + 1); |
| } |
| |
| boolean moved = false; |
| boolean showScroll = false; |
| switch (direction) { |
| case FOCUS_FORWARD: |
| if (selectedPosition < count - 1) { |
| // Move to the next item. |
| mLayoutMode = LAYOUT_MOVE_SELECTION; |
| setSelectionInt(selectedPosition + 1); |
| moved = true; |
| // Show the scrollbar only if changing rows. |
| showScroll = selectedPosition == endOfRow; |
| } |
| break; |
| |
| case FOCUS_BACKWARD: |
| if (selectedPosition > 0) { |
| // Move to the previous item. |
| mLayoutMode = LAYOUT_MOVE_SELECTION; |
| setSelectionInt(selectedPosition - 1); |
| moved = true; |
| // Show the scrollbar only if changing rows. |
| showScroll = selectedPosition == startOfRow; |
| } |
| break; |
| } |
| |
| if (moved) { |
| playSoundEffect(SoundEffectConstants.getContantForFocusDirection(direction)); |
| invokeOnItemScrollListener(); |
| } |
| |
| if (showScroll) { |
| awakenScrollBars(); |
| } |
| |
| return moved; |
| } |
| |
| @Override |
| protected void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) { |
| super.onFocusChanged(gainFocus, direction, previouslyFocusedRect); |
| |
| int closestChildIndex = -1; |
| if (gainFocus && previouslyFocusedRect != null) { |
| previouslyFocusedRect.offset(mScrollX, mScrollY); |
| |
| // figure out which item should be selected based on previously |
| // focused rect |
| Rect otherRect = mTempRect; |
| int minDistance = Integer.MAX_VALUE; |
| final int childCount = getChildCount(); |
| for (int i = 0; i < childCount; i++) { |
| // only consider view's on appropriate edge of grid |
| if (!isCandidateSelection(i, direction)) { |
| continue; |
| } |
| |
| final View other = getChildAt(i); |
| other.getDrawingRect(otherRect); |
| offsetDescendantRectToMyCoords(other, otherRect); |
| int distance = getDistance(previouslyFocusedRect, otherRect, direction); |
| |
| if (distance < minDistance) { |
| minDistance = distance; |
| closestChildIndex = i; |
| } |
| } |
| } |
| |
| if (closestChildIndex >= 0) { |
| setSelection(closestChildIndex + mFirstPosition); |
| } else { |
| requestLayout(); |
| } |
| } |
| |
| /** |
| * Is childIndex a candidate for next focus given the direction the focus |
| * change is coming from? |
| * @param childIndex The index to check. |
| * @param direction The direction, one of |
| * {FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT, FOCUS_FORWARD, FOCUS_BACKWARD} |
| * @return Whether childIndex is a candidate. |
| */ |
| private boolean isCandidateSelection(int childIndex, int direction) { |
| final int count = getChildCount(); |
| final int invertedIndex = count - 1 - childIndex; |
| |
| int rowStart; |
| int rowEnd; |
| |
| if (!mStackFromBottom) { |
| rowStart = childIndex - (childIndex % mNumColumns); |
| rowEnd = Math.max(rowStart + mNumColumns - 1, count); |
| } else { |
| rowEnd = count - 1 - (invertedIndex - (invertedIndex % mNumColumns)); |
| rowStart = Math.max(0, rowEnd - mNumColumns + 1); |
| } |
| |
| switch (direction) { |
| case View.FOCUS_RIGHT: |
| // coming from left, selection is only valid if it is on left |
| // edge |
| return childIndex == rowStart; |
| case View.FOCUS_DOWN: |
| // coming from top; only valid if in top row |
| return rowStart == 0; |
| case View.FOCUS_LEFT: |
| // coming from right, must be on right edge |
| return childIndex == rowEnd; |
| case View.FOCUS_UP: |
| // coming from bottom, need to be in last row |
| return rowEnd == count - 1; |
| case View.FOCUS_FORWARD: |
| // coming from top-left, need to be first in top row |
| return childIndex == rowStart && rowStart == 0; |
| case View.FOCUS_BACKWARD: |
| // coming from bottom-right, need to be last in bottom row |
| return childIndex == rowEnd && rowEnd == count - 1; |
| default: |
| throw new IllegalArgumentException("direction must be one of " |
| + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT, " |
| + "FOCUS_FORWARD, FOCUS_BACKWARD}."); |
| } |
| } |
| |
| /** |
| * Set the gravity for this grid. Gravity describes how the child views |
| * are horizontally aligned. Defaults to Gravity.LEFT |
| * |
| * @param gravity the gravity to apply to this grid's children |
| * |
| * @attr ref android.R.styleable#GridView_gravity |
| */ |
| public void setGravity(int gravity) { |
| if (mGravity != gravity) { |
| mGravity = gravity; |
| requestLayoutIfNecessary(); |
| } |
| } |
| |
| /** |
| * Describes how the child views are horizontally aligned. Defaults to Gravity.LEFT |
| * |
| * @return the gravity that will be applied to this grid's children |
| * |
| * @attr ref android.R.styleable#GridView_gravity |
| */ |
| public int getGravity() { |
| return mGravity; |
| } |
| |
| /** |
| * Set the amount of horizontal (x) spacing to place between each item |
| * in the grid. |
| * |
| * @param horizontalSpacing The amount of horizontal space between items, |
| * in pixels. |
| * |
| * @attr ref android.R.styleable#GridView_horizontalSpacing |
| */ |
| public void setHorizontalSpacing(int horizontalSpacing) { |
| if (horizontalSpacing != mRequestedHorizontalSpacing) { |
| mRequestedHorizontalSpacing = horizontalSpacing; |
| requestLayoutIfNecessary(); |
| } |
| } |
| |
| /** |
| * Returns the amount of horizontal spacing currently used between each item in the grid. |
| * |
| * <p>This is only accurate for the current layout. If {@link #setHorizontalSpacing(int)} |
| * has been called but layout is not yet complete, this method may return a stale value. |
| * To get the horizontal spacing that was explicitly requested use |
| * {@link #getRequestedHorizontalSpacing()}.</p> |
| * |
| * @return Current horizontal spacing between each item in pixels |
| * |
| * @see #setHorizontalSpacing(int) |
| * @see #getRequestedHorizontalSpacing() |
| * |
| * @attr ref android.R.styleable#GridView_horizontalSpacing |
| */ |
| public int getHorizontalSpacing() { |
| return mHorizontalSpacing; |
| } |
| |
| /** |
| * Returns the requested amount of horizontal spacing between each item in the grid. |
| * |
| * <p>The value returned may have been supplied during inflation as part of a style, |
| * the default GridView style, or by a call to {@link #setHorizontalSpacing(int)}. |
| * If layout is not yet complete or if GridView calculated a different horizontal spacing |
| * from what was requested, this may return a different value from |
| * {@link #getHorizontalSpacing()}.</p> |
| * |
| * @return The currently requested horizontal spacing between items, in pixels |
| * |
| * @see #setHorizontalSpacing(int) |
| * @see #getHorizontalSpacing() |
| * |
| * @attr ref android.R.styleable#GridView_horizontalSpacing |
| */ |
| public int getRequestedHorizontalSpacing() { |
| return mRequestedHorizontalSpacing; |
| } |
| |
| /** |
| * Set the amount of vertical (y) spacing to place between each item |
| * in the grid. |
| * |
| * @param verticalSpacing The amount of vertical space between items, |
| * in pixels. |
| * |
| * @see #getVerticalSpacing() |
| * |
| * @attr ref android.R.styleable#GridView_verticalSpacing |
| */ |
| public void setVerticalSpacing(int verticalSpacing) { |
| if (verticalSpacing != mVerticalSpacing) { |
| mVerticalSpacing = verticalSpacing; |
| requestLayoutIfNecessary(); |
| } |
| } |
| |
| /** |
| * Returns the amount of vertical spacing between each item in the grid. |
| * |
| * @return The vertical spacing between items in pixels |
| * |
| * @see #setVerticalSpacing(int) |
| * |
| * @attr ref android.R.styleable#GridView_verticalSpacing |
| */ |
| public int getVerticalSpacing() { |
| return mVerticalSpacing; |
| } |
| |
| /** |
| * Control how items are stretched to fill their space. |
| * |
| * @param stretchMode Either {@link #NO_STRETCH}, |
| * {@link #STRETCH_SPACING}, {@link #STRETCH_SPACING_UNIFORM}, or {@link #STRETCH_COLUMN_WIDTH}. |
| * |
| * @attr ref android.R.styleable#GridView_stretchMode |
| */ |
| public void setStretchMode(int stretchMode) { |
| if (stretchMode != mStretchMode) { |
| mStretchMode = stretchMode; |
| requestLayoutIfNecessary(); |
| } |
| } |
| |
| public int getStretchMode() { |
| return mStretchMode; |
| } |
| |
| /** |
| * Set the width of columns in the grid. |
| * |
| * @param columnWidth The column width, in pixels. |
| * |
| * @attr ref android.R.styleable#GridView_columnWidth |
| */ |
| public void setColumnWidth(int columnWidth) { |
| if (columnWidth != mRequestedColumnWidth) { |
| mRequestedColumnWidth = columnWidth; |
| requestLayoutIfNecessary(); |
| } |
| } |
| |
| /** |
| * Return the width of a column in the grid. |
| * |
| * <p>This may not be valid yet if a layout is pending.</p> |
| * |
| * @return The column width in pixels |
| * |
| * @see #setColumnWidth(int) |
| * @see #getRequestedColumnWidth() |
| * |
| * @attr ref android.R.styleable#GridView_columnWidth |
| */ |
| public int getColumnWidth() { |
| return mColumnWidth; |
| } |
| |
| /** |
| * Return the requested width of a column in the grid. |
| * |
| * <p>This may not be the actual column width used. Use {@link #getColumnWidth()} |
| * to retrieve the current real width of a column.</p> |
| * |
| * @return The requested column width in pixels |
| * |
| * @see #setColumnWidth(int) |
| * @see #getColumnWidth() |
| * |
| * @attr ref android.R.styleable#GridView_columnWidth |
| */ |
| public int getRequestedColumnWidth() { |
| return mRequestedColumnWidth; |
| } |
| |
| /** |
| * Set the number of columns in the grid |
| * |
| * @param numColumns The desired number of columns. |
| * |
| * @attr ref android.R.styleable#GridView_numColumns |
| */ |
| public void setNumColumns(int numColumns) { |
| if (numColumns != mRequestedNumColumns) { |
| mRequestedNumColumns = numColumns; |
| requestLayoutIfNecessary(); |
| } |
| } |
| |
| /** |
| * Get the number of columns in the grid. |
| * Returns {@link #AUTO_FIT} if the Grid has never been laid out. |
| * |
| * @attr ref android.R.styleable#GridView_numColumns |
| * |
| * @see #setNumColumns(int) |
| */ |
| @ViewDebug.ExportedProperty |
| public int getNumColumns() { |
| return mNumColumns; |
| } |
| |
| /** |
| * Make sure views are touching the top or bottom edge, as appropriate for |
| * our gravity |
| */ |
| private void adjustViewsUpOrDown() { |
| final int childCount = getChildCount(); |
| |
| if (childCount > 0) { |
| int delta; |
| View child; |
| |
| if (!mStackFromBottom) { |
| // Uh-oh -- we came up short. Slide all views up to make them |
| // align with the top |
| child = getChildAt(0); |
| delta = child.getTop() - mListPadding.top; |
| if (mFirstPosition != 0) { |
| // It's OK to have some space above the first item if it is |
| // part of the vertical spacing |
| delta -= mVerticalSpacing; |
| } |
| if (delta < 0) { |
| // We only are looking to see if we are too low, not too high |
| delta = 0; |
| } |
| } else { |
| // we are too high, slide all views down to align with bottom |
| child = getChildAt(childCount - 1); |
| delta = child.getBottom() - (getHeight() - mListPadding.bottom); |
| |
| if (mFirstPosition + childCount < mItemCount) { |
| // It's OK to have some space below the last item if it is |
| // part of the vertical spacing |
| delta += mVerticalSpacing; |
| } |
| |
| if (delta > 0) { |
| // We only are looking to see if we are too high, not too low |
| delta = 0; |
| } |
| } |
| |
| if (delta != 0) { |
| offsetChildrenTopAndBottom(-delta); |
| } |
| } |
| } |
| |
| @Override |
| protected int computeVerticalScrollExtent() { |
| final int count = getChildCount(); |
| if (count > 0) { |
| final int numColumns = mNumColumns; |
| final int rowCount = (count + numColumns - 1) / numColumns; |
| |
| int extent = rowCount * 100; |
| |
| View view = getChildAt(0); |
| final int top = view.getTop(); |
| int height = view.getHeight(); |
| if (height > 0) { |
| extent += (top * 100) / height; |
| } |
| |
| view = getChildAt(count - 1); |
| final int bottom = view.getBottom(); |
| height = view.getHeight(); |
| if (height > 0) { |
| extent -= ((bottom - getHeight()) * 100) / height; |
| } |
| |
| return extent; |
| } |
| return 0; |
| } |
| |
| @Override |
| protected int computeVerticalScrollOffset() { |
| if (mFirstPosition >= 0 && getChildCount() > 0) { |
| final View view = getChildAt(0); |
| final int top = view.getTop(); |
| int height = view.getHeight(); |
| if (height > 0) { |
| final int numColumns = mNumColumns; |
| final int rowCount = (mItemCount + numColumns - 1) / numColumns; |
| // In case of stackFromBottom the calculation of whichRow needs |
| // to take into account that counting from the top the first row |
| // might not be entirely filled. |
| final int oddItemsOnFirstRow = isStackFromBottom() ? ((rowCount * numColumns) - |
| mItemCount) : 0; |
| final int whichRow = (mFirstPosition + oddItemsOnFirstRow) / numColumns; |
| return Math.max(whichRow * 100 - (top * 100) / height + |
| (int) ((float) mScrollY / getHeight() * rowCount * 100), 0); |
| } |
| } |
| return 0; |
| } |
| |
| @Override |
| protected int computeVerticalScrollRange() { |
| // TODO: Account for vertical spacing too |
| final int numColumns = mNumColumns; |
| final int rowCount = (mItemCount + numColumns - 1) / numColumns; |
| int result = Math.max(rowCount * 100, 0); |
| if (mScrollY != 0) { |
| // Compensate for overscroll |
| result += Math.abs((int) ((float) mScrollY / getHeight() * rowCount * 100)); |
| } |
| return result; |
| } |
| |
| @Override |
| public void onInitializeAccessibilityEvent(AccessibilityEvent event) { |
| super.onInitializeAccessibilityEvent(event); |
| event.setClassName(GridView.class.getName()); |
| } |
| |
| @Override |
| public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) { |
| super.onInitializeAccessibilityNodeInfo(info); |
| info.setClassName(GridView.class.getName()); |
| } |
| } |