Allow Canvas.setBitmap() to receive a null Bitmap.

Change-Id: I6096f0b44866e532ccd96a29c816bf34d48c1dc2

4 files changed, 19 insertions, 9 deletions

diff --git a/core/java/android/view/View.java b/core/java/android/view/View.java
index dd7eaa9ee9e0..c270fd4d037e 100644
--- a/core/java/android/view/View.java
+++ b/core/java/android/view/View.java
@@ -10287,6 +10287,7 @@ public class View implements Drawable.Callback2, KeyEvent.Callback, Accessibilit
         canvas.restoreToCount(restoreCount);
 
         if (attachInfo != null) {
+            canvas.setBitmap(null);
             // Restore the cached Canvas for our siblings
             attachInfo.mCanvas = canvas;
         }
diff --git a/core/jni/android/graphics/Canvas.cpp b/core/jni/android/graphics/Canvas.cpp
index 682c3c4a25fb..f8be136f4866 100644
--- a/core/jni/android/graphics/Canvas.cpp
+++ b/core/jni/android/graphics/Canvas.cpp
@@ -88,9 +88,12 @@ public:
         return canvas->getDevice()->accessBitmap(false).height();
     }
 
-    static void setBitmap(JNIEnv* env, jobject, SkCanvas* canvas,
-                          SkBitmap* bitmap) {
-        canvas->setBitmapDevice(*bitmap);
+    static void setBitmap(JNIEnv* env, jobject, SkCanvas* canvas, SkBitmap* bitmap) {
+        if (bitmap) {
+            canvas->setBitmapDevice(*bitmap);
+        } else {
+            canvas->setDevice(NULL);
+        }
     }
  
     static int saveAll(JNIEnv* env, jobject jcanvas) {
diff --git a/graphics/java/android/graphics/Canvas.java b/graphics/java/android/graphics/Canvas.java
index 35ed4d2087cc..6ae8c9ba17ae 100644
--- a/graphics/java/android/graphics/Canvas.java
+++ b/graphics/java/android/graphics/Canvas.java
@@ -178,17 +178,22 @@ public class Canvas {
      * @see #getDensity()
      */
     public void setBitmap(Bitmap bitmap) {
-        if (!bitmap.isMutable()) {
-            throw new IllegalStateException();
-        }
         if (isHardwareAccelerated()) {
             throw new RuntimeException("Can't set a bitmap device on a GL canvas");
         }
-        throwIfRecycled(bitmap);
 
-        native_setBitmap(mNativeCanvas, bitmap.ni());
+        int pointer = 0;
+        if (bitmap != null) {
+            if (!bitmap.isMutable()) {
+                throw new IllegalStateException();
+            }
+            throwIfRecycled(bitmap);
+            mDensity = bitmap.mDensity;
+            pointer = bitmap.ni();
+        }
+
+        native_setBitmap(mNativeCanvas, pointer);
         mBitmap = bitmap;
-        mDensity = bitmap.mDensity;
     }
     
     /**
diff --git a/tests/HwAccelerationTest/src/com/android/test/hwui/PathsActivity.java b/tests/HwAccelerationTest/src/com/android/test/hwui/PathsActivity.java
index 833b61caae0f..c241a6243011 100644
--- a/tests/HwAccelerationTest/src/com/android/test/hwui/PathsActivity.java
+++ b/tests/HwAccelerationTest/src/com/android/test/hwui/PathsActivity.java
@@ -101,6 +101,7 @@ public class PathsActivity extends Activity {
             Canvas canvas = new Canvas(mBitmap);
             canvas.translate(-mPathBounds.left + mOffset * 1.5f, -mPathBounds.top + mOffset * 1.5f);
             canvas.drawPath(mPath, mMediumPaint);
+            canvas.setBitmap(null);
         }
 
         @Override