LayoutLib: Reuse canvas when possible.

Also moved the prepare/cleanupThread methods to Bridge
as they are not really specific to the scene anymore.

Change-Id: I7b93821913ce4d2fcbe3d8be489be6533ff87e57

1 files changed, 19 insertions, 7 deletions

diff --git a/tools/layoutlib/bridge/src/android/graphics/Canvas_Delegate.java b/tools/layoutlib/bridge/src/android/graphics/Canvas_Delegate.java
index b901e0d..bc6ad64 100644
--- a/tools/layoutlib/bridge/src/android/graphics/Canvas_Delegate.java
+++ b/tools/layoutlib/bridge/src/android/graphics/Canvas_Delegate.java
@@ -92,13 +92,6 @@ public class Canvas_Delegate {
         return mGraphicsStack.peek();
     }
 
-    /**
-     * Disposes of the {@link Graphics2D} stack.
-     */
-    public void dispose() {
-
-    }
-
     // ---- native methods ----
 
     /*package*/ static boolean isOpaque(Canvas thisCanvas) {
@@ -985,6 +978,16 @@ public class Canvas_Delegate {
     }
 
     /*package*/ static void finalizer(int nativeCanvas) {
+        // get the delegate from the native int so that it can be disposed.
+        Canvas_Delegate canvasDelegate = sManager.getDelegate(nativeCanvas);
+        if (canvasDelegate == null) {
+            assert false;
+            return;
+        }
+
+        canvasDelegate.dispose();
+
+        // remove it from the manager.
         sManager.removeDelegate(nativeCanvas);
     }
 
@@ -997,6 +1000,15 @@ public class Canvas_Delegate {
     private Canvas_Delegate() {
     }
 
+    /**
+     * Disposes of the {@link Graphics2D} stack.
+     */
+    private void dispose() {
+        while (mGraphicsStack.size() > 0) {
+            mGraphicsStack.pop().dispose();
+        }
+    }
+
     private void setBitmap(BufferedImage image) {
         mBufferedImage = image;
         mGraphicsStack.push(mBufferedImage.createGraphics());