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diff --git a/core/java/android/view/ViewStub.java b/core/java/android/view/ViewStub.java
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+/*
+ * 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 com.android.internal.R;
+
+/**
+ * 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>
+ *     &lt;ViewStub android:id="@+id/stub"
+ *               android:inflatedId="@+id/subTree"
+ *               android:layout="@layout/mySubTree"
+ *               android:layout_width="120dip"
+ *               android:layout_height="40dip" /&gt;
+ * </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
+ */
+public final class ViewStub extends View {
+    private int mLayoutResource = 0;
+    private int mInflatedId;
+
+    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 defStyle) {
+        TypedArray a = context.obtainStyledAttributes(attrs, com.android.internal.R.styleable.ViewStub,
+                defStyle, 0);
+
+        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, defStyle, 0);
+        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
+     */
+    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
+     */
+    public void setLayoutResource(int layoutResource) {
+        mLayoutResource = layoutResource;
+    }
+
+    @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.
+     *
+     * @param visibility One of {@link #VISIBLE}, {@link #INVISIBLE}, or {@link #GONE}.
+     *
+     * @see #inflate() 
+     */
+    @Override
+    public void setVisibility(int visibility) {
+        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 = 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);
+                }
+
+                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);
+    }
+}