| /* |
| * Copyright (C) 2008 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.view; |
| |
| import android.content.Context; |
| import android.content.res.TypedArray; |
| import android.graphics.Canvas; |
| import android.util.AttributeSet; |
| import android.widget.RemoteViews.RemoteView; |
| |
| import com.android.internal.R; |
| |
| import java.lang.ref.WeakReference; |
| |
| /** |
| * A ViewStub is an invisible, zero-sized View that can be used to lazily inflate |
| * layout resources at runtime. |
| * |
| * When a ViewStub is made visible, or when {@link #inflate()} is invoked, the layout resource |
| * is inflated. The ViewStub then replaces itself in its parent with the inflated View or Views. |
| * Therefore, the ViewStub exists in the view hierarchy until {@link #setVisibility(int)} or |
| * {@link #inflate()} is invoked. |
| * |
| * The inflated View is added to the ViewStub's parent with the ViewStub's layout |
| * parameters. Similarly, you can define/override the inflate View's id by using the |
| * ViewStub's inflatedId property. For instance: |
| * |
| * <pre> |
| * <ViewStub android:id="@+id/stub" |
| * android:inflatedId="@+id/subTree" |
| * android:layout="@layout/mySubTree" |
| * android:layout_width="120dip" |
| * android:layout_height="40dip" /> |
| * </pre> |
| * |
| * The ViewStub thus defined can be found using the id "stub." After inflation of |
| * the layout resource "mySubTree," the ViewStub is removed from its parent. The |
| * View created by inflating the layout resource "mySubTree" can be found using the |
| * id "subTree," specified by the inflatedId property. The inflated View is finally |
| * assigned a width of 120dip and a height of 40dip. |
| * |
| * The preferred way to perform the inflation of the layout resource is the following: |
| * |
| * <pre> |
| * ViewStub stub = (ViewStub) findViewById(R.id.stub); |
| * View inflated = stub.inflate(); |
| * </pre> |
| * |
| * When {@link #inflate()} is invoked, the ViewStub is replaced by the inflated View |
| * and the inflated View is returned. This lets applications get a reference to the |
| * inflated View without executing an extra findViewById(). |
| * |
| * @attr ref android.R.styleable#ViewStub_inflatedId |
| * @attr ref android.R.styleable#ViewStub_layout |
| */ |
| @RemoteView |
| public final class ViewStub extends View { |
| private int mLayoutResource = 0; |
| private int mInflatedId; |
| |
| private WeakReference<View> mInflatedViewRef; |
| |
| private LayoutInflater mInflater; |
| private OnInflateListener mInflateListener; |
| |
| public ViewStub(Context context) { |
| initialize(context); |
| } |
| |
| /** |
| * Creates a new ViewStub with the specified layout resource. |
| * |
| * @param context The application's environment. |
| * @param layoutResource The reference to a layout resource that will be inflated. |
| */ |
| public ViewStub(Context context, int layoutResource) { |
| mLayoutResource = layoutResource; |
| initialize(context); |
| } |
| |
| public ViewStub(Context context, AttributeSet attrs) { |
| this(context, attrs, 0); |
| } |
| |
| @SuppressWarnings({"UnusedDeclaration"}) |
| public ViewStub(Context context, AttributeSet attrs, int defStyleAttr) { |
| this(context, attrs, defStyleAttr, 0); |
| } |
| |
| public ViewStub(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { |
| TypedArray a = context.obtainStyledAttributes( |
| attrs, com.android.internal.R.styleable.ViewStub, defStyleAttr, defStyleRes); |
| |
| mInflatedId = a.getResourceId(R.styleable.ViewStub_inflatedId, NO_ID); |
| mLayoutResource = a.getResourceId(R.styleable.ViewStub_layout, 0); |
| |
| a.recycle(); |
| |
| a = context.obtainStyledAttributes( |
| attrs, com.android.internal.R.styleable.View, defStyleAttr, defStyleRes); |
| mID = a.getResourceId(R.styleable.View_id, NO_ID); |
| a.recycle(); |
| |
| initialize(context); |
| } |
| |
| private void initialize(Context context) { |
| mContext = context; |
| setVisibility(GONE); |
| setWillNotDraw(true); |
| } |
| |
| /** |
| * Returns the id taken by the inflated view. If the inflated id is |
| * {@link View#NO_ID}, the inflated view keeps its original id. |
| * |
| * @return A positive integer used to identify the inflated view or |
| * {@link #NO_ID} if the inflated view should keep its id. |
| * |
| * @see #setInflatedId(int) |
| * @attr ref android.R.styleable#ViewStub_inflatedId |
| */ |
| public int getInflatedId() { |
| return mInflatedId; |
| } |
| |
| /** |
| * Defines the id taken by the inflated view. If the inflated id is |
| * {@link View#NO_ID}, the inflated view keeps its original id. |
| * |
| * @param inflatedId A positive integer used to identify the inflated view or |
| * {@link #NO_ID} if the inflated view should keep its id. |
| * |
| * @see #getInflatedId() |
| * @attr ref android.R.styleable#ViewStub_inflatedId |
| */ |
| @android.view.RemotableViewMethod |
| public void setInflatedId(int inflatedId) { |
| mInflatedId = inflatedId; |
| } |
| |
| /** |
| * Returns the layout resource that will be used by {@link #setVisibility(int)} or |
| * {@link #inflate()} to replace this StubbedView |
| * in its parent by another view. |
| * |
| * @return The layout resource identifier used to inflate the new View. |
| * |
| * @see #setLayoutResource(int) |
| * @see #setVisibility(int) |
| * @see #inflate() |
| * @attr ref android.R.styleable#ViewStub_layout |
| */ |
| public int getLayoutResource() { |
| return mLayoutResource; |
| } |
| |
| /** |
| * Specifies the layout resource to inflate when this StubbedView becomes visible or invisible |
| * or when {@link #inflate()} is invoked. The View created by inflating the layout resource is |
| * used to replace this StubbedView in its parent. |
| * |
| * @param layoutResource A valid layout resource identifier (different from 0.) |
| * |
| * @see #getLayoutResource() |
| * @see #setVisibility(int) |
| * @see #inflate() |
| * @attr ref android.R.styleable#ViewStub_layout |
| */ |
| @android.view.RemotableViewMethod |
| public void setLayoutResource(int layoutResource) { |
| mLayoutResource = layoutResource; |
| } |
| |
| /** |
| * Set {@link LayoutInflater} to use in {@link #inflate()}, or {@code null} |
| * to use the default. |
| */ |
| public void setLayoutInflater(LayoutInflater inflater) { |
| mInflater = inflater; |
| } |
| |
| /** |
| * Get current {@link LayoutInflater} used in {@link #inflate()}. |
| */ |
| public LayoutInflater getLayoutInflater() { |
| return mInflater; |
| } |
| |
| @Override |
| protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { |
| setMeasuredDimension(0, 0); |
| } |
| |
| @Override |
| public void draw(Canvas canvas) { |
| } |
| |
| @Override |
| protected void dispatchDraw(Canvas canvas) { |
| } |
| |
| /** |
| * When visibility is set to {@link #VISIBLE} or {@link #INVISIBLE}, |
| * {@link #inflate()} is invoked and this StubbedView is replaced in its parent |
| * by the inflated layout resource. After that calls to this function are passed |
| * through to the inflated view. |
| * |
| * @param visibility One of {@link #VISIBLE}, {@link #INVISIBLE}, or {@link #GONE}. |
| * |
| * @see #inflate() |
| */ |
| @Override |
| @android.view.RemotableViewMethod |
| public void setVisibility(int visibility) { |
| if (mInflatedViewRef != null) { |
| View view = mInflatedViewRef.get(); |
| if (view != null) { |
| view.setVisibility(visibility); |
| } else { |
| throw new IllegalStateException("setVisibility called on un-referenced view"); |
| } |
| } else { |
| super.setVisibility(visibility); |
| if (visibility == VISIBLE || visibility == INVISIBLE) { |
| inflate(); |
| } |
| } |
| } |
| |
| /** |
| * Inflates the layout resource identified by {@link #getLayoutResource()} |
| * and replaces this StubbedView in its parent by the inflated layout resource. |
| * |
| * @return The inflated layout resource. |
| * |
| */ |
| public View inflate() { |
| final ViewParent viewParent = getParent(); |
| |
| if (viewParent != null && viewParent instanceof ViewGroup) { |
| if (mLayoutResource != 0) { |
| final ViewGroup parent = (ViewGroup) viewParent; |
| final LayoutInflater factory; |
| if (mInflater != null) { |
| factory = mInflater; |
| } else { |
| factory = LayoutInflater.from(mContext); |
| } |
| final View view = factory.inflate(mLayoutResource, parent, |
| false); |
| |
| if (mInflatedId != NO_ID) { |
| view.setId(mInflatedId); |
| } |
| |
| final int index = parent.indexOfChild(this); |
| parent.removeViewInLayout(this); |
| |
| final ViewGroup.LayoutParams layoutParams = getLayoutParams(); |
| if (layoutParams != null) { |
| parent.addView(view, index, layoutParams); |
| } else { |
| parent.addView(view, index); |
| } |
| |
| mInflatedViewRef = new WeakReference<View>(view); |
| |
| if (mInflateListener != null) { |
| mInflateListener.onInflate(this, view); |
| } |
| |
| return view; |
| } else { |
| throw new IllegalArgumentException("ViewStub must have a valid layoutResource"); |
| } |
| } else { |
| throw new IllegalStateException("ViewStub must have a non-null ViewGroup viewParent"); |
| } |
| } |
| |
| /** |
| * Specifies the inflate listener to be notified after this ViewStub successfully |
| * inflated its layout resource. |
| * |
| * @param inflateListener The OnInflateListener to notify of successful inflation. |
| * |
| * @see android.view.ViewStub.OnInflateListener |
| */ |
| public void setOnInflateListener(OnInflateListener inflateListener) { |
| mInflateListener = inflateListener; |
| } |
| |
| /** |
| * Listener used to receive a notification after a ViewStub has successfully |
| * inflated its layout resource. |
| * |
| * @see android.view.ViewStub#setOnInflateListener(android.view.ViewStub.OnInflateListener) |
| */ |
| public static interface OnInflateListener { |
| /** |
| * Invoked after a ViewStub successfully inflated its layout resource. |
| * This method is invoked after the inflated view was added to the |
| * hierarchy but before the layout pass. |
| * |
| * @param stub The ViewStub that initiated the inflation. |
| * @param inflated The inflated View. |
| */ |
| void onInflate(ViewStub stub, View inflated); |
| } |
| } |