src/com/cooliris/media/TimeBar.java - platform/packages/apps/Gallery3D - Git at Google

 package com.cooliris.media;

 import java.util.ArrayList;
 import java.util.Calendar;
 import java.util.GregorianCalendar;
 import java.util.HashMap;

 import javax.microedition.khronos.opengles.GL11;

 import android.content.Context;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 import android.graphics.Canvas;
 import android.graphics.NinePatch;
 import android.graphics.Paint;
 import android.graphics.PorterDuff;
 import android.graphics.PorterDuffXfermode;
 import android.graphics.Rect;
 import android.util.SparseArray;
 import android.view.MotionEvent;
 import com.cooliris.media.RenderView.Lists;

 public final class TimeBar extends Layer implements MediaFeed.Listener {
     public static final int HEIGHT = 48;
     private static final int MARKER_SPACING_PIXELS = 50;
     private static final float AUTO_SCROLL_MARGIN = 100f;
     private static final Paint SRC_PAINT = new Paint();
     private Listener mListener = null;
     private MediaFeed mFeed = null;
     private float mTotalWidth = 0f;
     private float mPosition = 0f;
     private float mPositionAnim = 0f;
     private float mScroll = 0f;
     private float mScrollAnim = 0f;
     private boolean mInDrag = false;
     private float mDragX = 0f;

     private ArrayList<Marker> mMarkers = new ArrayList<Marker>();
     private ArrayList<Marker> mMarkersCopy = new ArrayList<Marker>();

     private static final int KNOB = R.drawable.scroller_new;
     private static final int KNOB_PRESSED = R.drawable.scroller_pressed_new;
     private final StringTexture.Config mMonthYearFormat = new StringTexture.Config();
     private final StringTexture.Config mDayFormat = new StringTexture.Config();
     private final SparseArray<StringTexture> mYearLabels = new SparseArray<StringTexture>();
     private StringTexture mDateUnknown;
     private final StringTexture[] mMonthLabels = new StringTexture[12];
     private final StringTexture[] mDayLabels = new StringTexture[32];
     private final StringTexture[] mOpaqueDayLabels = new StringTexture[32];
     private final StringTexture mDot = new StringTexture("¥");
     private final HashMap<MediaItem, Marker> mTracker = new HashMap<MediaItem, Marker>(1024);
     private int mState;
     private float mTextAlpha = 0.0f;
     private float mAnimTextAlpha = 0.0f;
     private boolean mShowTime;
     private NinePatch mBackground;
     private Rect mBackgroundRect;
     private BitmapTexture mBackgroundTexture;

     public interface Listener {
         public void onTimeChanged(TimeBar timebar);
     }

     TimeBar(Context context) {
         // Setup formatting for text labels.
         mMonthYearFormat.fontSize = 17f * Gallery.PIXEL_DENSITY;
         mMonthYearFormat.bold = true;
         mMonthYearFormat.a = 0.85f;
         mDayFormat.fontSize = 17f * Gallery.PIXEL_DENSITY;
         mDayFormat.a = 0.61f;
         regenerateStringsForContext(context);
         Bitmap background = BitmapFactory.decodeResource(context.getResources(), R.drawable.popup);
         mBackground = new NinePatch(background, background.getNinePatchChunk(), null);
         mBackgroundRect = new Rect();
         SRC_PAINT.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC));
     }

     public void regenerateStringsForContext(Context context) {
         // Create textures for month names.
         String[] months = context.getResources().getStringArray(R.array.months_abbreviated);
         for (int i = 0; i < months.length; ++i) {
             mMonthLabels[i] = new StringTexture(months[i], mMonthYearFormat);
         }

         for (int i = 0; i <= 31; ++i) {
             mDayLabels[i] = new StringTexture(Integer.toString(i), mDayFormat);
             mOpaqueDayLabels[i] = new StringTexture(Integer.toString(i), mMonthYearFormat);
         }
         mDateUnknown = new StringTexture(context.getResources().getString(R.string.date_unknown), mMonthYearFormat);
         mBackgroundTexture = null;
     }

     public void setListener(Listener listener) {
         mListener = listener;
     }

     public void setFeed(MediaFeed feed, int state, boolean needsLayout) {
         mFeed = feed;
         mState = state;
         layout();
         if (needsLayout) {
             mPosition = 0;
             mScroll = getScrollForPosition(mPosition);
         }
     }

     @Override
     protected void onSizeChanged() {
         mScroll = getScrollForPosition(mPosition);
     }

     public MediaItem getItem() {
         synchronized (mMarkers) {
             // x is between 0 and 1.0f
             int numMarkers = mMarkers.size();
             if (numMarkers == 0)
                 return null;
             int index = (int) (mPosition * (numMarkers));
             if (index >= numMarkers)
                 index = numMarkers - 1;
             Marker marker = mMarkers.get(index);
             if (marker != null) {
                 // we have to find the index of the media item depending upon
                 // the value of mPosition
                 float deltaBetweenMarkers = 1.0f / numMarkers;
                 float increment = mPosition - index * deltaBetweenMarkers;
                 // if (increment > deltaBetweenMarkers)
                 // increment = deltaBetweenMarkers;
                 // if (increment < 0)
                 // increment = 0;
                 ArrayList<MediaItem> items = marker.items;
                 int numItems = items.size();
                 if (numItems == 0)
                     return null;
                 int itemIndex = (int) ((numItems) * increment / deltaBetweenMarkers);
                 if (itemIndex >= numItems)
                     itemIndex = numItems - 1;
                 return marker.items.get(itemIndex);
             }
         }
         return null;
     }

     private Marker getAnchorMarker() {
         synchronized (mMarkers) {
             // x is between 0 and 1.0f
             int numMarkers = mMarkers.size();
             if (numMarkers == 0)
                 return null;
             int index = (int) (mPosition * (numMarkers));
             if (index >= numMarkers)
                 index = numMarkers - 1;
             Marker marker = mMarkers.get(index);
             return marker;
         }
     }

     public void setItem(MediaItem item) {
         Marker marker = mTracker.get(item);
         if (marker != null) {
             float markerX = (mTotalWidth == 0.0f) ? 0.0f : marker.x / mTotalWidth;
             mPosition = Math.max(0.0f, Math.min(1.0f, markerX));
             mScroll = getScrollForPosition(mPosition);
         }
     }

     private void layout() {
         if (mFeed != null) {
             // Clear existing markers.
             mTracker.clear();
             synchronized (mMarkers) {
                 mMarkers.clear();
             }
             float scrollX = mScroll;
             // Place markers for every time interval that intersects one of the
             // clusters.
             // Markers for a full month would be for example: Jan 5 10 15 20 25
             // 30.
             MediaFeed feed = mFeed;
             int lastYear = -1;
             int lastMonth = -1;
             int lastDayBlock = -1;
             float dx = 0f;
             int increment = 12;
             MediaSet set = null;
             mShowTime = true;
             if (mState == GridLayer.STATE_GRID_VIEW) {
                 set = feed.getFilteredSet();
                 if (set == null) {
                     set = feed.getCurrentSet();
                 }
             } else {
                 increment = 2;
                 if (!feed.hasExpandedMediaSet()) {
                     mShowTime = false;
                 }
                 set = new MediaSet();
                 int numSlots = feed.getNumSlots();
                 for (int i = 0; i < numSlots; ++i) {
                     MediaSet slotSet = feed.getSetForSlot(i);
                     if (slotSet != null) {
                         ArrayList<MediaItem> slotSetItems = slotSet.getItems();
                         if (slotSetItems != null && slotSet.getNumItems() > 0) {
                             MediaItem item = slotSetItems.get(0);
                             if (item != null) {
                                 set.addItem(item);
                             }
                         }
                     }
                 }
             }
             if (set != null) {
                 GregorianCalendar time = new GregorianCalendar();
                 ArrayList<MediaItem> items = set.getItems();
                 if (items != null) {
                     int j = 0;
                     while (j < set.getNumItems()) {
                         final MediaItem item = items.get(j);
                         if (item == null)
                             continue;
                         time.setTimeInMillis(item.mDateTakenInMs);
                         // Detect year rollovers.
                         final int year = time.get(Calendar.YEAR);
                         if (year != lastYear) {
                             lastYear = year;
                             lastMonth = -1;
                             lastDayBlock = -1;
                         }
                         Marker marker = null;
                         // Detect month rollovers and emit a month marker.
                         final int month = time.get(Calendar.MONTH);
                         final int dayBlock = time.get(Calendar.DATE);
                         if (month != lastMonth) {
                             lastMonth = month;
                             lastDayBlock = -1;
                             marker = new Marker(dx, time.getTimeInMillis(), year, month, dayBlock,
                                     Marker.TYPE_MONTH, increment);
                             dx = addMarker(marker);
                         } else if (dayBlock != lastDayBlock) {
                             lastDayBlock = dayBlock;
                             if (dayBlock != 0) {
                                 marker = new Marker(dx, time.getTimeInMillis(), year, month, dayBlock,
                                         Marker.TYPE_DAY, increment);
                                 dx = addMarker(marker);
                             }
                         } else {
                             marker = new Marker(dx, time.getTimeInMillis(), year, month, dayBlock, Marker.TYPE_DOT, increment);
                             dx = addMarker(marker);
                         }
                         for (int k = 0; k < increment; ++k) {
                             int index = k + j;
                             if (index < 0)
                                 continue;
                             if (index >= items.size())
                                 break;
                             if (index == items.size() - 1 && k != 0)
                                 break;
                             MediaItem thisItem = items.get(index);
                             marker.items.add(thisItem);
                             mTracker.put(thisItem, marker);
                         }
                         if (j == items.size() - 1)
                             break;
                         j += increment;
                         if (j >= items.size() - 1)
                             j = items.size() - 1;
                     }
                 }
                 mTotalWidth = dx - MARKER_SPACING_PIXELS * Gallery.PIXEL_DENSITY;
             }
             mPosition = getPositionForScroll(scrollX);
             mPositionAnim = mPosition;
             synchronized (mMarkersCopy) {
                 int numMarkers = mMarkers.size();
                 mMarkersCopy.clear();
                 mMarkersCopy.ensureCapacity(numMarkers);
                 for (int i = 0; i < numMarkers; ++i) {
                     mMarkersCopy.add(mMarkers.get(i));
                 }
             }
         }
     }

     private float addMarker(Marker marker) {
         mMarkers.add(marker);
         return marker.x + MARKER_SPACING_PIXELS * Gallery.PIXEL_DENSITY;
     }

     /*
      * private float getKnobXForPosition(float position) { return position * (mTotalWidth - mKnob.getWidth()); }
      *
      * private float getPositionForKnobX(float knobX) { return Math.max(0f, Math.min(1f, knobX / (mTotalWidth - mKnob.getWidth())));
      * }
      *
      * private float getScrollForPosition(float position) { return position * (mTotalWidth - mWidth);// - (1f - 2f * position) *
      * MARKER_SPACING_PIXELS; }
      */

     private float getScrollForPosition(float position) {
         // Map position [0, 1] to scroll [-visibleWidth/2, totalWidth -
         // visibleWidth/2].
         // This has the effect of centering the scroll knob on screen.
         float halfWidth = mWidth * 0.5f;
         float positionInv = 1f - position;
         float centered = positionInv * -halfWidth + position * (mTotalWidth - halfWidth);
         return centered;
     }

     private float getPositionForScroll(float scroll) {
         float halfWidth = mWidth * 0.5f;
         if (mTotalWidth == 0)
             return 0;
         return ((scroll + halfWidth) / (mTotalWidth));
     }

     private float getKnobXForPosition(float position) {
         return position * mTotalWidth;
     }

     private float getPositionForKnobX(float knobX) {
         float normKnobX = (mTotalWidth == 0) ? 0 : knobX / mTotalWidth;
         return Math.max(0f, Math.min(1f, normKnobX));
     }

     @Override
     public boolean update(RenderView view, float dt) {
         // Update animations.
         final float ratio = Math.min(1f, 10f * dt);
         final float invRatio = 1f - ratio;
         mPositionAnim = ratio * mPosition + invRatio * mPositionAnim;
         mScrollAnim = ratio * mScroll + invRatio * mScrollAnim;
         // Handle autoscroll.
         if (mInDrag) {
             final float x = getKnobXForPosition(mPosition) - mScrollAnim;
             float velocity;
             float autoScrollMargin = AUTO_SCROLL_MARGIN * Gallery.PIXEL_DENSITY;
             if (x < autoScrollMargin) {
                 velocity = -(float) Math.pow((1f - x / autoScrollMargin), 2);
             } else if (x > mWidth - autoScrollMargin) {
                 velocity = (float) Math.pow(1f - (mWidth - x) / autoScrollMargin, 2);
             } else {
                 velocity = 0;
             }
             mScroll += velocity * 400f * dt;
             mPosition = getPositionForKnobX(mDragX + mScroll);
             mTextAlpha = 1.0f;
         } else {
             mTextAlpha = 0.0f;
         }
         mAnimTextAlpha = FloatUtils.animate(mAnimTextAlpha, mTextAlpha, dt);
         return mAnimTextAlpha != mTextAlpha;
     }

     @Override
     public void renderBlended(RenderView view, GL11 gl) {
         final float originX = mX;
         final float originY = mY;
         final float scrollOffset = mScrollAnim;
         final float scrolledOriginX = originX - scrollOffset;
         final float position = mPositionAnim;
         final int knobId = mInDrag ? KNOB_PRESSED : KNOB;
         final Texture knob = view.getResource(knobId);
         // Draw the scroller knob.
         if (!mShowTime) {
             if (view.bind(knob)) {
                 final float knobWidth = knob.getWidth();
                 view.draw2D(scrolledOriginX + getKnobXForPosition(position) - knobWidth * 0.5f, originY, 0f, knobWidth, knob
                         .getHeight());
             }
         } else {
             if (view.bind(knob)) {
                 final float knobWidth = knob.getWidth();
                 final float knobHeight = knob.getHeight();
                 view.draw2D(scrolledOriginX + getKnobXForPosition(position) - knobWidth * 0.5f, view.getHeight() - knobHeight, 0f,
                         knobWidth, knobHeight);
             }
             // we draw the current time on top of the knob
             if (mInDrag || mAnimTextAlpha != 0.0f) {
                 Marker anchor = getAnchorMarker();
                 if (anchor != null) {
                     Texture month = mMonthLabels[anchor.month];
                     Texture day = mOpaqueDayLabels[anchor.day];
                     Texture year = getYearLabel(anchor.year);
                     boolean validDate = true;
                     if (anchor.year <= 1970) {
                         month = mDateUnknown;
                         day = null;
                         year = null;
                         validDate = false;
                     }
                     view.loadTexture(month);
                     if (validDate) {
                         view.loadTexture(day);
                         view.loadTexture(year);
                     }
                     int numPixelsBufferX = 70;
                     float expectedWidth = month.getWidth()
                             + ((validDate) ? (day.getWidth() + year.getWidth() + 10 * Gallery.PIXEL_DENSITY) : 0);
                     if ((expectedWidth + numPixelsBufferX * Gallery.PIXEL_DENSITY) != mBackgroundRect.right) {
                         mBackgroundRect.right = (int) (expectedWidth + numPixelsBufferX * Gallery.PIXEL_DENSITY);
                         mBackgroundRect.bottom = (int) (month.getHeight() + 20 * Gallery.PIXEL_DENSITY);
                         try {
                             Bitmap bitmap = Bitmap.createBitmap(mBackgroundRect.right, mBackgroundRect.bottom,
                                     Bitmap.Config.ARGB_8888);
                             Canvas canvas = new Canvas();
                             canvas.setBitmap(bitmap);
                             mBackground.draw(canvas, mBackgroundRect, SRC_PAINT);
                             mBackgroundTexture = new BitmapTexture(bitmap);
                             view.loadTexture(mBackgroundTexture);
                             bitmap.recycle();
                         } catch (OutOfMemoryError e) {
                             // Do nothing.
                         }
                     }
                     gl.glTexEnvf(GL11.GL_TEXTURE_ENV, GL11.GL_TEXTURE_ENV_MODE, GL11.GL_MODULATE);
                     gl.glColor4f(mAnimTextAlpha, mAnimTextAlpha, mAnimTextAlpha, mAnimTextAlpha);
                     float x = (view.getWidth() - expectedWidth - numPixelsBufferX * Gallery.PIXEL_DENSITY) / 2;
                     float y = (view.getHeight() - 10 * Gallery.PIXEL_DENSITY) * 0.5f;
                     if (mBackgroundTexture != null) {
                         view.draw2D(mBackgroundTexture, x, y);
                     }
                     y = view.getHeight() * 0.5f;
                     x = (view.getWidth() - expectedWidth) / 2;
                     view.draw2D(month, x, y);
                     if (validDate) {
                         x += month.getWidth() + 3 * Gallery.PIXEL_DENSITY;
                         view.draw2D(day, x, y);
                         x += day.getWidth() + 7 * Gallery.PIXEL_DENSITY;
                         view.draw2D(year, x, y);
                     }
                     if (mAnimTextAlpha != 1f) {
                         gl.glColor4f(1f, 1f, 1f, 1f);
                     }
                     gl.glTexEnvf(GL11.GL_TEXTURE_ENV, GL11.GL_TEXTURE_ENV_MODE, GL11.GL_REPLACE);
                 }
             }
         }
     }

     @Override
     public boolean onTouchEvent(MotionEvent event) {
         // Set position on touch movement.
         mDragX = event.getX();
         mPosition = getPositionForKnobX(mDragX + mScroll);

         // Notify the listener.
         if (mListener != null) {
             mListener.onTimeChanged(this);
         }

         // Update state when touch begins and ends.
         switch (event.getAction()) {
         case MotionEvent.ACTION_DOWN:
             mInDrag = true;
             break;
         case MotionEvent.ACTION_UP:
         case MotionEvent.ACTION_CANCEL:
             // mScroll = getScrollForPosition(mPosition);
             mInDrag = false;

             // Clamp to the nearest marker.
             setItem(getItem());
         default:
             break;
         }

         return true;
     }

     public void onFeedChanged(MediaFeed feed, boolean needsLayout) {
         layout();
     }

     private static final class Marker {
         Marker(float x, long time, int year, int month, int day, int type, int expectedCapacity) {
             this.x = x;
             this.year = year;
             this.month = month;
             this.day = day;
             this.items = new ArrayList<MediaItem>(expectedCapacity);
         }

         public static final int TYPE_MONTH = 1;
         public static final int TYPE_DAY = 2;
         public static final int TYPE_DOT = 3;
         public ArrayList<MediaItem> items;
         public final float x;
         public final int year;
         public final int month;
         public final int day;
     }

     @Override
     public void generate(RenderView view, Lists lists) {
         lists.updateList.add(this);
         lists.blendedList.add(this);
         lists.hitTestList.add(this);
     }

     public void onFeedAboutToChange(MediaFeed feed) {
         // nothing needs to be done
         return;
     }

     private StringTexture getYearLabel(int year) {
         if (year <= 1970)
             return mDot;
         StringTexture label = mYearLabels.get(year);
         if (label == null) {
             label = new StringTexture(Integer.toString(year), mMonthYearFormat);
             mYearLabels.put(year, label);
         }
         return label;
     }

     public boolean isDragged() {
         return mInDrag;
     }
 }
	package com.cooliris.media;

	import java.util.ArrayList;
	import java.util.Calendar;
	import java.util.GregorianCalendar;
	import java.util.HashMap;

	import javax.microedition.khronos.opengles.GL11;

	import android.content.Context;
	import android.graphics.Bitmap;
	import android.graphics.BitmapFactory;
	import android.graphics.Canvas;
	import android.graphics.NinePatch;
	import android.graphics.Paint;
	import android.graphics.PorterDuff;
	import android.graphics.PorterDuffXfermode;
	import android.graphics.Rect;
	import android.util.SparseArray;
	import android.view.MotionEvent;
	import com.cooliris.media.RenderView.Lists;

	public final class TimeBar extends Layer implements MediaFeed.Listener {
	public static final int HEIGHT = 48;
	private static final int MARKER_SPACING_PIXELS = 50;
	private static final float AUTO_SCROLL_MARGIN = 100f;
	private static final Paint SRC_PAINT = new Paint();
	private Listener mListener = null;
	private MediaFeed mFeed = null;
	private float mTotalWidth = 0f;
	private float mPosition = 0f;
	private float mPositionAnim = 0f;
	private float mScroll = 0f;
	private float mScrollAnim = 0f;
	private boolean mInDrag = false;
	private float mDragX = 0f;

	private ArrayList<Marker> mMarkers = new ArrayList<Marker>();
	private ArrayList<Marker> mMarkersCopy = new ArrayList<Marker>();

	private static final int KNOB = R.drawable.scroller_new;
	private static final int KNOB_PRESSED = R.drawable.scroller_pressed_new;
	private final StringTexture.Config mMonthYearFormat = new StringTexture.Config();
	private final StringTexture.Config mDayFormat = new StringTexture.Config();
	private final SparseArray<StringTexture> mYearLabels = new SparseArray<StringTexture>();
	private StringTexture mDateUnknown;
	private final StringTexture[] mMonthLabels = new StringTexture[12];
	private final StringTexture[] mDayLabels = new StringTexture[32];
	private final StringTexture[] mOpaqueDayLabels = new StringTexture[32];
	private final StringTexture mDot = new StringTexture("¥");
	private final HashMap<MediaItem, Marker> mTracker = new HashMap<MediaItem, Marker>(1024);
	private int mState;
	private float mTextAlpha = 0.0f;
	private float mAnimTextAlpha = 0.0f;
	private boolean mShowTime;
	private NinePatch mBackground;
	private Rect mBackgroundRect;
	private BitmapTexture mBackgroundTexture;

	public interface Listener {
	public void onTimeChanged(TimeBar timebar);
	}

	TimeBar(Context context) {
	// Setup formatting for text labels.
	mMonthYearFormat.fontSize = 17f * Gallery.PIXEL_DENSITY;
	mMonthYearFormat.bold = true;
	mMonthYearFormat.a = 0.85f;
	mDayFormat.fontSize = 17f * Gallery.PIXEL_DENSITY;
	mDayFormat.a = 0.61f;
	regenerateStringsForContext(context);
	Bitmap background = BitmapFactory.decodeResource(context.getResources(), R.drawable.popup);
	mBackground = new NinePatch(background, background.getNinePatchChunk(), null);
	mBackgroundRect = new Rect();
	SRC_PAINT.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC));
	}

	public void regenerateStringsForContext(Context context) {
	// Create textures for month names.
	String[] months = context.getResources().getStringArray(R.array.months_abbreviated);
	for (int i = 0; i < months.length; ++i) {
	mMonthLabels[i] = new StringTexture(months[i], mMonthYearFormat);
	}

	for (int i = 0; i <= 31; ++i) {
	mDayLabels[i] = new StringTexture(Integer.toString(i), mDayFormat);
	mOpaqueDayLabels[i] = new StringTexture(Integer.toString(i), mMonthYearFormat);
	}
	mDateUnknown = new StringTexture(context.getResources().getString(R.string.date_unknown), mMonthYearFormat);
	mBackgroundTexture = null;
	}

	public void setListener(Listener listener) {
	mListener = listener;
	}

	public void setFeed(MediaFeed feed, int state, boolean needsLayout) {
	mFeed = feed;
	mState = state;
	layout();
	if (needsLayout) {
	mPosition = 0;
	mScroll = getScrollForPosition(mPosition);
	}
	}

	@Override
	protected void onSizeChanged() {
	mScroll = getScrollForPosition(mPosition);
	}

	public MediaItem getItem() {
	synchronized (mMarkers) {
	// x is between 0 and 1.0f
	int numMarkers = mMarkers.size();
	if (numMarkers == 0)
	return null;
	int index = (int) (mPosition * (numMarkers));
	if (index >= numMarkers)
	index = numMarkers - 1;
	Marker marker = mMarkers.get(index);
	if (marker != null) {
	// we have to find the index of the media item depending upon
	// the value of mPosition
	float deltaBetweenMarkers = 1.0f / numMarkers;
	float increment = mPosition - index * deltaBetweenMarkers;
	// if (increment > deltaBetweenMarkers)
	// increment = deltaBetweenMarkers;
	// if (increment < 0)
	// increment = 0;
	ArrayList<MediaItem> items = marker.items;
	int numItems = items.size();
	if (numItems == 0)
	return null;
	int itemIndex = (int) ((numItems) * increment / deltaBetweenMarkers);
	if (itemIndex >= numItems)
	itemIndex = numItems - 1;
	return marker.items.get(itemIndex);
	}
	}
	return null;
	}

	private Marker getAnchorMarker() {
	synchronized (mMarkers) {
	// x is between 0 and 1.0f
	int numMarkers = mMarkers.size();
	if (numMarkers == 0)
	return null;
	int index = (int) (mPosition * (numMarkers));
	if (index >= numMarkers)
	index = numMarkers - 1;
	Marker marker = mMarkers.get(index);
	return marker;
	}
	}

	public void setItem(MediaItem item) {
	Marker marker = mTracker.get(item);
	if (marker != null) {
	float markerX = (mTotalWidth == 0.0f) ? 0.0f : marker.x / mTotalWidth;
	mPosition = Math.max(0.0f, Math.min(1.0f, markerX));
	mScroll = getScrollForPosition(mPosition);
	}
	}

	private void layout() {
	if (mFeed != null) {
	// Clear existing markers.
	mTracker.clear();
	synchronized (mMarkers) {
	mMarkers.clear();
	}
	float scrollX = mScroll;
	// Place markers for every time interval that intersects one of the
	// clusters.
	// Markers for a full month would be for example: Jan 5 10 15 20 25
	// 30.
	MediaFeed feed = mFeed;
	int lastYear = -1;
	int lastMonth = -1;
	int lastDayBlock = -1;
	float dx = 0f;
	int increment = 12;
	MediaSet set = null;
	mShowTime = true;
	if (mState == GridLayer.STATE_GRID_VIEW) {
	set = feed.getFilteredSet();
	if (set == null) {
	set = feed.getCurrentSet();
	}
	} else {
	increment = 2;
	if (!feed.hasExpandedMediaSet()) {
	mShowTime = false;
	}
	set = new MediaSet();
	int numSlots = feed.getNumSlots();
	for (int i = 0; i < numSlots; ++i) {
	MediaSet slotSet = feed.getSetForSlot(i);
	if (slotSet != null) {
	ArrayList<MediaItem> slotSetItems = slotSet.getItems();
	if (slotSetItems != null && slotSet.getNumItems() > 0) {
	MediaItem item = slotSetItems.get(0);
	if (item != null) {
	set.addItem(item);
	}
	}
	}
	}
	}
	if (set != null) {
	GregorianCalendar time = new GregorianCalendar();
	ArrayList<MediaItem> items = set.getItems();
	if (items != null) {
	int j = 0;
	while (j < set.getNumItems()) {
	final MediaItem item = items.get(j);
	if (item == null)
	continue;
	time.setTimeInMillis(item.mDateTakenInMs);
	// Detect year rollovers.
	final int year = time.get(Calendar.YEAR);
	if (year != lastYear) {
	lastYear = year;
	lastMonth = -1;
	lastDayBlock = -1;
	}
	Marker marker = null;
	// Detect month rollovers and emit a month marker.
	final int month = time.get(Calendar.MONTH);
	final int dayBlock = time.get(Calendar.DATE);
	if (month != lastMonth) {
	lastMonth = month;
	lastDayBlock = -1;
	marker = new Marker(dx, time.getTimeInMillis(), year, month, dayBlock,
	Marker.TYPE_MONTH, increment);
	dx = addMarker(marker);
	} else if (dayBlock != lastDayBlock) {
	lastDayBlock = dayBlock;
	if (dayBlock != 0) {
	marker = new Marker(dx, time.getTimeInMillis(), year, month, dayBlock,
	Marker.TYPE_DAY, increment);
	dx = addMarker(marker);
	}
	} else {
	marker = new Marker(dx, time.getTimeInMillis(), year, month, dayBlock, Marker.TYPE_DOT, increment);
	dx = addMarker(marker);
	}
	for (int k = 0; k < increment; ++k) {
	int index = k + j;
	if (index < 0)
	continue;
	if (index >= items.size())
	break;
	if (index == items.size() - 1 && k != 0)
	break;
	MediaItem thisItem = items.get(index);
	marker.items.add(thisItem);
	mTracker.put(thisItem, marker);
	}
	if (j == items.size() - 1)
	break;
	j += increment;
	if (j >= items.size() - 1)
	j = items.size() - 1;
	}
	}
	mTotalWidth = dx - MARKER_SPACING_PIXELS * Gallery.PIXEL_DENSITY;
	}
	mPosition = getPositionForScroll(scrollX);
	mPositionAnim = mPosition;
	synchronized (mMarkersCopy) {
	int numMarkers = mMarkers.size();
	mMarkersCopy.clear();
	mMarkersCopy.ensureCapacity(numMarkers);
	for (int i = 0; i < numMarkers; ++i) {
	mMarkersCopy.add(mMarkers.get(i));
	}
	}
	}
	}

	private float addMarker(Marker marker) {
	mMarkers.add(marker);
	return marker.x + MARKER_SPACING_PIXELS * Gallery.PIXEL_DENSITY;
	}

	/*
	* private float getKnobXForPosition(float position) { return position * (mTotalWidth - mKnob.getWidth()); }
	*
	* private float getPositionForKnobX(float knobX) { return Math.max(0f, Math.min(1f, knobX / (mTotalWidth - mKnob.getWidth())));
	* }
	*
	* private float getScrollForPosition(float position) { return position * (mTotalWidth - mWidth);// - (1f - 2f * position) *
	* MARKER_SPACING_PIXELS; }
	*/

	private float getScrollForPosition(float position) {
	// Map position [0, 1] to scroll [-visibleWidth/2, totalWidth -
	// visibleWidth/2].
	// This has the effect of centering the scroll knob on screen.
	float halfWidth = mWidth * 0.5f;
	float positionInv = 1f - position;
	float centered = positionInv * -halfWidth + position * (mTotalWidth - halfWidth);
	return centered;
	}

	private float getPositionForScroll(float scroll) {
	float halfWidth = mWidth * 0.5f;
	if (mTotalWidth == 0)
	return 0;
	return ((scroll + halfWidth) / (mTotalWidth));
	}

	private float getKnobXForPosition(float position) {
	return position * mTotalWidth;
	}

	private float getPositionForKnobX(float knobX) {
	float normKnobX = (mTotalWidth == 0) ? 0 : knobX / mTotalWidth;
	return Math.max(0f, Math.min(1f, normKnobX));
	}

	@Override
	public boolean update(RenderView view, float dt) {
	// Update animations.
	final float ratio = Math.min(1f, 10f * dt);
	final float invRatio = 1f - ratio;
	mPositionAnim = ratio * mPosition + invRatio * mPositionAnim;
	mScrollAnim = ratio * mScroll + invRatio * mScrollAnim;
	// Handle autoscroll.
	if (mInDrag) {
	final float x = getKnobXForPosition(mPosition) - mScrollAnim;
	float velocity;
	float autoScrollMargin = AUTO_SCROLL_MARGIN * Gallery.PIXEL_DENSITY;
	if (x < autoScrollMargin) {
	velocity = -(float) Math.pow((1f - x / autoScrollMargin), 2);
	} else if (x > mWidth - autoScrollMargin) {
	velocity = (float) Math.pow(1f - (mWidth - x) / autoScrollMargin, 2);
	} else {
	velocity = 0;
	}
	mScroll += velocity * 400f * dt;
	mPosition = getPositionForKnobX(mDragX + mScroll);
	mTextAlpha = 1.0f;
	} else {
	mTextAlpha = 0.0f;
	}
	mAnimTextAlpha = FloatUtils.animate(mAnimTextAlpha, mTextAlpha, dt);
	return mAnimTextAlpha != mTextAlpha;
	}

	@Override
	public void renderBlended(RenderView view, GL11 gl) {
	final float originX = mX;
	final float originY = mY;
	final float scrollOffset = mScrollAnim;
	final float scrolledOriginX = originX - scrollOffset;
	final float position = mPositionAnim;
	final int knobId = mInDrag ? KNOB_PRESSED : KNOB;
	final Texture knob = view.getResource(knobId);
	// Draw the scroller knob.
	if (!mShowTime) {
	if (view.bind(knob)) {
	final float knobWidth = knob.getWidth();
	view.draw2D(scrolledOriginX + getKnobXForPosition(position) - knobWidth * 0.5f, originY, 0f, knobWidth, knob
	.getHeight());
	}
	} else {
	if (view.bind(knob)) {
	final float knobWidth = knob.getWidth();
	final float knobHeight = knob.getHeight();
	view.draw2D(scrolledOriginX + getKnobXForPosition(position) - knobWidth * 0.5f, view.getHeight() - knobHeight, 0f,
	knobWidth, knobHeight);
	}
	// we draw the current time on top of the knob
	if (mInDrag \|\| mAnimTextAlpha != 0.0f) {
	Marker anchor = getAnchorMarker();
	if (anchor != null) {
	Texture month = mMonthLabels[anchor.month];
	Texture day = mOpaqueDayLabels[anchor.day];
	Texture year = getYearLabel(anchor.year);
	boolean validDate = true;
	if (anchor.year <= 1970) {
	month = mDateUnknown;
	day = null;
	year = null;
	validDate = false;
	}
	view.loadTexture(month);
	if (validDate) {
	view.loadTexture(day);
	view.loadTexture(year);
	}
	int numPixelsBufferX = 70;
	float expectedWidth = month.getWidth()
	+ ((validDate) ? (day.getWidth() + year.getWidth() + 10 * Gallery.PIXEL_DENSITY) : 0);
	if ((expectedWidth + numPixelsBufferX * Gallery.PIXEL_DENSITY) != mBackgroundRect.right) {
	mBackgroundRect.right = (int) (expectedWidth + numPixelsBufferX * Gallery.PIXEL_DENSITY);
	mBackgroundRect.bottom = (int) (month.getHeight() + 20 * Gallery.PIXEL_DENSITY);
	try {
	Bitmap bitmap = Bitmap.createBitmap(mBackgroundRect.right, mBackgroundRect.bottom,
	Bitmap.Config.ARGB_8888);
	Canvas canvas = new Canvas();
	canvas.setBitmap(bitmap);
	mBackground.draw(canvas, mBackgroundRect, SRC_PAINT);
	mBackgroundTexture = new BitmapTexture(bitmap);
	view.loadTexture(mBackgroundTexture);
	bitmap.recycle();
	} catch (OutOfMemoryError e) {
	// Do nothing.
	}
	}
	gl.glTexEnvf(GL11.GL_TEXTURE_ENV, GL11.GL_TEXTURE_ENV_MODE, GL11.GL_MODULATE);
	gl.glColor4f(mAnimTextAlpha, mAnimTextAlpha, mAnimTextAlpha, mAnimTextAlpha);
	float x = (view.getWidth() - expectedWidth - numPixelsBufferX * Gallery.PIXEL_DENSITY) / 2;
	float y = (view.getHeight() - 10 * Gallery.PIXEL_DENSITY) * 0.5f;
	if (mBackgroundTexture != null) {
	view.draw2D(mBackgroundTexture, x, y);
	}
	y = view.getHeight() * 0.5f;
	x = (view.getWidth() - expectedWidth) / 2;
	view.draw2D(month, x, y);
	if (validDate) {
	x += month.getWidth() + 3 * Gallery.PIXEL_DENSITY;
	view.draw2D(day, x, y);
	x += day.getWidth() + 7 * Gallery.PIXEL_DENSITY;
	view.draw2D(year, x, y);
	}
	if (mAnimTextAlpha != 1f) {
	gl.glColor4f(1f, 1f, 1f, 1f);
	}
	gl.glTexEnvf(GL11.GL_TEXTURE_ENV, GL11.GL_TEXTURE_ENV_MODE, GL11.GL_REPLACE);
	}
	}
	}
	}

	@Override
	public boolean onTouchEvent(MotionEvent event) {
	// Set position on touch movement.
	mDragX = event.getX();
	mPosition = getPositionForKnobX(mDragX + mScroll);

	// Notify the listener.
	if (mListener != null) {
	mListener.onTimeChanged(this);
	}

	// Update state when touch begins and ends.
	switch (event.getAction()) {
	case MotionEvent.ACTION_DOWN:
	mInDrag = true;
	break;
	case MotionEvent.ACTION_UP:
	case MotionEvent.ACTION_CANCEL:
	// mScroll = getScrollForPosition(mPosition);
	mInDrag = false;

	// Clamp to the nearest marker.
	setItem(getItem());
	default:
	break;
	}

	return true;
	}

	public void onFeedChanged(MediaFeed feed, boolean needsLayout) {
	layout();
	}

	private static final class Marker {
	Marker(float x, long time, int year, int month, int day, int type, int expectedCapacity) {
	this.x = x;
	this.year = year;
	this.month = month;
	this.day = day;
	this.items = new ArrayList<MediaItem>(expectedCapacity);
	}

	public static final int TYPE_MONTH = 1;
	public static final int TYPE_DAY = 2;
	public static final int TYPE_DOT = 3;
	public ArrayList<MediaItem> items;
	public final float x;
	public final int year;
	public final int month;
	public final int day;
	}

	@Override
	public void generate(RenderView view, Lists lists) {
	lists.updateList.add(this);
	lists.blendedList.add(this);
	lists.hitTestList.add(this);
	}

	public void onFeedAboutToChange(MediaFeed feed) {
	// nothing needs to be done
	return;
	}

	private StringTexture getYearLabel(int year) {
	if (year <= 1970)
	return mDot;
	StringTexture label = mYearLabels.get(year);
	if (label == null) {
	label = new StringTexture(Integer.toString(year), mMonthYearFormat);
	mYearLabels.put(year, label);
	}
	return label;
	}

	public boolean isDragged() {
	return mInDrag;
	}
	}