Update layers' opaque property when needed

Before this change, changing a View's opacity would not be reflected
by hardware layers. This could cause layers to retain their previous
opacity.

Change-Id: Iba2c8b4242deca021651df9324cc7c585a64653d

Author: Romain Guy

core/java/android/view/GLES20Canvas.java

@@ -151,6 +151,7 @@ protected void finalize() throws Throwable {
     static native int nCreateTextureLayer(boolean opaque, int[] layerInfo);
     static native int nCreateLayer(int width, int height, boolean isOpaque, int[] layerInfo);
     static native void nResizeLayer(int layerId, int width, int height, int[] layerInfo);
+    static native void nSetOpaqueLayer(int layerId, boolean isOpaque);
     static native void nUpdateTextureLayer(int layerId, int width, int height, boolean opaque,
             SurfaceTexture surface);
     static native void nSetTextureLayerTransform(int layerId, int matrix);

core/java/android/view/GLES20Layer.java

@@ -46,11 +46,6 @@ public int getLayer() {
     boolean copyInto(Bitmap bitmap) {
         return GLES20Canvas.nCopyLayer(mLayer, bitmap.mNativeBitmap);
     }
-    
-    @Override
-    void update(int width, int height, boolean isOpaque) {
-        super.update(width, height, isOpaque);
-    }
 
     @Override
     void destroy() {

core/java/android/view/GLES20RenderLayer.java

@@ -70,6 +70,12 @@ void resize(int width, int height) {
         }
     }
 
+    @Override
+    void setOpaque(boolean isOpaque) {
+        mOpaque = isOpaque;
+        GLES20Canvas.nSetOpaqueLayer(mLayer, isOpaque);
+    }
+
     @Override
     HardwareCanvas getCanvas() {
         return mCanvas;

core/java/android/view/GLES20TextureLayer.java

@@ -42,12 +42,6 @@ class GLES20TextureLayer extends GLES20Layer {
         }        
     }
 
-    GLES20TextureLayer(SurfaceTexture surface, boolean isOpaque) {
-        this(isOpaque);
-        mSurface = surface;
-        mSurface.attachToGLContext(mTexture);
-    }
-
     @Override
     boolean isValid() {
         return mLayer != 0 && mTexture != 0;
@@ -92,6 +86,11 @@ void update(int width, int height, boolean isOpaque) {
         GLES20Canvas.nUpdateTextureLayer(mLayer, width, height, isOpaque, mSurface);
     }
 
+    @Override
+    void setOpaque(boolean isOpaque) {
+        throw new UnsupportedOperationException("Use update(int, int, boolean) instead");
+    }
+
     @Override
     void setTransform(Matrix matrix) {
         GLES20Canvas.nSetTextureLayerTransform(mLayer, matrix.native_instance);

core/java/android/view/HardwareLayer.java

@@ -106,6 +106,13 @@ boolean isOpaque() {
         return mOpaque;
     }
 
+    /**
+     * Sets whether or not this layer should be considered opaque.
+     * 
+     * @param isOpaque True if the layer is opaque, false otherwise
+     */
+    abstract void setOpaque(boolean isOpaque);
+
     /**
      * Indicates whether this layer can be rendered.
      * 

core/java/android/view/View.java

@@ -11928,9 +11928,24 @@ HardwareLayer getHardwareLayer() {
                 mHardwareLayer = mAttachInfo.mHardwareRenderer.createHardwareLayer(
                         width, height, isOpaque());
                 mLocalDirtyRect.set(0, 0, width, height);
-            } else if (mHardwareLayer.getWidth() != width || mHardwareLayer.getHeight() != height) {
-                mHardwareLayer.resize(width, height);
-                mLocalDirtyRect.set(0, 0, width, height);
+            } else {
+                if (mHardwareLayer.getWidth() != width || mHardwareLayer.getHeight() != height) {
+                    mHardwareLayer.resize(width, height);
+                    mLocalDirtyRect.set(0, 0, width, height);
+                }
+
+                // This should not be necessary but applications that change
+                // the parameters of their background drawable without calling
+                // this.setBackground(Drawable) can leave the view in a bad state
+                // (for instance isOpaque() returns true, but the background is
+                // not opaque.)
+                computeOpaqueFlags();
+
+                final boolean opaque = isOpaque();
+                if (mHardwareLayer.isOpaque() != opaque) {
+                    mHardwareLayer.setOpaque(opaque);
+                    mLocalDirtyRect.set(0, 0, width, height);
+                }
             }
 
             // The layer is not valid if the underlying GPU resources cannot be allocated
@@ -13989,6 +14004,8 @@ public void setBackground(Drawable background) {
      */
     @Deprecated
     public void setBackgroundDrawable(Drawable background) {
+        computeOpaqueFlags();
+
         if (background == mBackground) {
             return;
         }

core/jni/android_view_GLES20Canvas.cpp

@@ -769,6 +769,13 @@ static void android_view_GLES20Canvas_resizeLayer(JNIEnv* env, jobject clazz,
     env->ReleaseIntArrayElements(layerInfo, storage, 0);
 }
 
+static void android_view_GLES20Canvas_setOpaqueLayer(JNIEnv* env, jobject clazz,
+        Layer* layer, jboolean isOpaque) {
+    if (layer) {
+        layer->setBlend(!isOpaque);
+    }
+}
+
 static void android_view_GLES20Canvas_updateTextureLayer(JNIEnv* env, jobject clazz,
         Layer* layer, jint width, jint height, jboolean isOpaque, jobject surface) {
     float transform[16];
@@ -969,6 +976,7 @@ static JNINativeMethod gMethods[] = {
     { "nCreateLayerRenderer",    "(I)I",       (void*) android_view_GLES20Canvas_createLayerRenderer },
     { "nCreateLayer",            "(IIZ[I)I",   (void*) android_view_GLES20Canvas_createLayer },
     { "nResizeLayer",            "(III[I)V" ,  (void*) android_view_GLES20Canvas_resizeLayer },
+    { "nSetOpaqueLayer",         "(IZ)V",      (void*) android_view_GLES20Canvas_setOpaqueLayer },
     { "nCreateTextureLayer",     "(Z[I)I",     (void*) android_view_GLES20Canvas_createTextureLayer },
     { "nUpdateTextureLayer",     "(IIIZLandroid/graphics/SurfaceTexture;)V",
             (void*) android_view_GLES20Canvas_updateTextureLayer },