Added support for async inflation of RemoteViews

When enabled, the View inflation as well as some of the drawable
loading is done on the background thread.
It also assumes that all the views support inflation on the
background thread, which is true for the default views
supported by the platform

For ViewGroup opetations, it maintains a virtual view tree which
is used for findViewById. The final operations are applied on
the UI thread in the end.

Change-Id: Ib3ce55182ec04a344f2b2513981ee03afc8fa2e8

1 files changed, 83 insertions, 36 deletions

diff --git a/core/java/android/widget/ImageView.java b/core/java/android/widget/ImageView.java
index 6e90baf26fa2..f601f7df1fa8 100644
--- a/core/java/android/widget/ImageView.java
+++ b/core/java/android/widget/ImageView.java
@@ -392,6 +392,26 @@ public class ImageView extends View {
         return mDrawable;
     }
 
+    private class ImageDrawableCallback implements Runnable {
+
+        private final Drawable drawable;
+        private final Uri uri;
+        private final int resource;
+
+        ImageDrawableCallback(Drawable drawable, Uri uri, int resource) {
+            this.drawable = drawable;
+            this.uri = uri;
+            this.resource = resource;
+        }
+
+        @Override
+        public void run() {
+            setImageDrawable(drawable);
+            mUri = uri;
+            mResource = resource;
+        }
+    }
+
     /**
      * Sets a drawable as the content of this ImageView.
      *
@@ -405,7 +425,7 @@ public class ImageView extends View {
      *
      * @attr ref android.R.styleable#ImageView_src
      */
-    @android.view.RemotableViewMethod
+    @android.view.RemotableViewMethod(asyncImpl="setImageResourceAsync")
     public void setImageResource(@DrawableRes int resId) {
         // The resource configuration may have changed, so we should always
         // try to load the resource even if the resId hasn't changed.
@@ -424,6 +444,11 @@ public class ImageView extends View {
         invalidate();
     }
 
+    /** @hide **/
+    public Runnable setImageResourceAsync(@DrawableRes int resId) {
+        return new ImageDrawableCallback(getContext().getDrawable(resId), null, resId);
+    }
+
     /**
      * Sets the content of this ImageView to the specified Uri.
      *
@@ -435,7 +460,7 @@ public class ImageView extends View {
      *
      * @param uri the Uri of an image, or {@code null} to clear the content
      */
-    @android.view.RemotableViewMethod
+    @android.view.RemotableViewMethod(asyncImpl="setImageURIAsync")
     public void setImageURI(@Nullable Uri uri) {
         if (mResource != 0 || (mUri != uri && (uri == null || mUri == null || !uri.equals(mUri)))) {
             updateDrawable(null);
@@ -454,6 +479,19 @@ public class ImageView extends View {
         }
     }
 
+    /** @hide **/
+    public Runnable setImageURIAsync(@Nullable Uri uri) {
+        if (mResource != 0 || (mUri != uri && (uri == null || mUri == null || !uri.equals(mUri)))) {
+            Drawable d = uri == null ? null : getDrawableFromUri(uri);
+            if (d == null) {
+                // Do not set the URI if the drawable couldn't be loaded.
+                uri = null;
+            }
+            return new ImageDrawableCallback(d, uri, 0);
+        }
+        return null;
+    }
+
     /**
      * Sets a drawable as the content of this ImageView.
      *
@@ -490,11 +528,16 @@ public class ImageView extends View {
      * @param icon an Icon holding the desired image, or {@code null} to clear
      *             the content
      */
-    @android.view.RemotableViewMethod
+    @android.view.RemotableViewMethod(asyncImpl="setImageIconAsync")
     public void setImageIcon(@Nullable Icon icon) {
         setImageDrawable(icon == null ? null : icon.loadDrawable(mContext));
     }
 
+    /** @hide **/
+    public Runnable setImageIconAsync(@Nullable Icon icon) {
+        return new ImageDrawableCallback(icon == null ? null : icon.loadDrawable(mContext), null, 0);
+    }
+
     /**
      * Applies a tint to the image drawable. Does not modify the current tint
      * mode, which is {@link PorterDuff.Mode#SRC_IN} by default.
@@ -786,8 +829,7 @@ public class ImageView extends View {
             return;
         }
 
-        final Resources res = getResources();
-        if (res == null) {
+        if (getResources() == null) {
             return;
         }
 
@@ -802,37 +844,7 @@ public class ImageView extends View {
                 mUri = null;
             }
         } else if (mUri != null) {
-            final String scheme = mUri.getScheme();
-            if (ContentResolver.SCHEME_ANDROID_RESOURCE.equals(scheme)) {
-                try {
-                    // Load drawable through Resources, to get the source density information
-                    ContentResolver.OpenResourceIdResult r =
-                            mContext.getContentResolver().getResourceId(mUri);
-                    d = r.r.getDrawable(r.id, mContext.getTheme());
-                } catch (Exception e) {
-                    Log.w(LOG_TAG, "Unable to open content: " + mUri, e);
-                }
-            } else if (ContentResolver.SCHEME_CONTENT.equals(scheme)
-                    || ContentResolver.SCHEME_FILE.equals(scheme)) {
-                InputStream stream = null;
-                try {
-                    stream = mContext.getContentResolver().openInputStream(mUri);
-                    d = Drawable.createFromResourceStream(
-                            mUseCorrectStreamDensity ? res : null, null, stream, null);
-                } catch (Exception e) {
-                    Log.w(LOG_TAG, "Unable to open content: " + mUri, e);
-                } finally {
-                    if (stream != null) {
-                        try {
-                            stream.close();
-                        } catch (IOException e) {
-                            Log.w(LOG_TAG, "Unable to close content: " + mUri, e);
-                        }
-                    }
-                }
-            } else {
-                d = Drawable.createFromPath(mUri.toString());
-            }
+            d = getDrawableFromUri(mUri);
 
             if (d == null) {
                 Log.w(LOG_TAG, "resolveUri failed on bad bitmap uri: " + mUri);
@@ -846,6 +858,41 @@ public class ImageView extends View {
         updateDrawable(d);
     }
 
+    private Drawable getDrawableFromUri(Uri uri) {
+        final String scheme = uri.getScheme();
+        if (ContentResolver.SCHEME_ANDROID_RESOURCE.equals(scheme)) {
+            try {
+                // Load drawable through Resources, to get the source density information
+                ContentResolver.OpenResourceIdResult r =
+                        mContext.getContentResolver().getResourceId(uri);
+                return r.r.getDrawable(r.id, mContext.getTheme());
+            } catch (Exception e) {
+                Log.w(LOG_TAG, "Unable to open content: " + uri, e);
+            }
+        } else if (ContentResolver.SCHEME_CONTENT.equals(scheme)
+                || ContentResolver.SCHEME_FILE.equals(scheme)) {
+            InputStream stream = null;
+            try {
+                stream = mContext.getContentResolver().openInputStream(uri);
+                return Drawable.createFromResourceStream(
+                        mUseCorrectStreamDensity ? getResources() : null, null, stream, null);
+            } catch (Exception e) {
+                Log.w(LOG_TAG, "Unable to open content: " + uri, e);
+            } finally {
+                if (stream != null) {
+                    try {
+                        stream.close();
+                    } catch (IOException e) {
+                        Log.w(LOG_TAG, "Unable to close content: " + uri, e);
+                    }
+                }
+            }
+        } else {
+            return Drawable.createFromPath(uri.toString());
+        }
+        return null;
+    }
+
     @Override
     public int[] onCreateDrawableState(int extraSpace) {
         if (mState == null) {