4 files changed, 21 insertions, 12 deletions

diff --git a/core/jni/android/graphics/Picture.cpp b/core/jni/android/graphics/Picture.cpp
index d048a29..b0d943e 100644
--- a/core/jni/android/graphics/Picture.cpp
+++ b/core/jni/android/graphics/Picture.cpp
@@ -42,10 +42,6 @@ Canvas* Picture::beginRecording(int width, int height) {
     mWidth = width;
     mHeight = height;
     SkCanvas* canvas = mRecorder->beginRecording(width, height, NULL, 0);
-    // the java side will wrap this guy in a Canvas.java, which will call
-    // unref in its finalizer, so we have to ref it here, so that both that
-    // Canvas.java and our picture can both be owners
-    canvas->ref();
     return Canvas::create_canvas(canvas);
 }
 
diff --git a/core/jni/android/graphics/SkiaCanvas.cpp b/core/jni/android/graphics/SkiaCanvas.cpp
index 793d177..7de54c4 100644
--- a/core/jni/android/graphics/SkiaCanvas.cpp
+++ b/core/jni/android/graphics/SkiaCanvas.cpp
@@ -44,10 +44,18 @@ namespace android {
 // Holds an SkCanvas reference plus additional native data.
 class SkiaCanvas : public Canvas {
 public:
-    SkiaCanvas(SkBitmap* bitmap);
-
-    SkiaCanvas(SkCanvas* canvas) : mCanvas(canvas) {
+    explicit SkiaCanvas(SkBitmap* bitmap);
+
+    /**
+     *  Create a new SkiaCanvas.
+     *
+     *  @param canvas SkCanvas to handle calls made to this SkiaCanvas. Must
+     *      not be NULL. This constructor will ref() the SkCanvas, and unref()
+     *      it in its destructor.
+     */
+    explicit SkiaCanvas(SkCanvas* canvas) : mCanvas(canvas) {
         SkASSERT(canvas);
+        canvas->ref();
     }
 
     virtual SkCanvas* getSkCanvas() {
diff --git a/core/jni/android/graphics/pdf/PdfDocument.cpp b/core/jni/android/graphics/pdf/PdfDocument.cpp
index be90612..8ba164f 100644
--- a/core/jni/android/graphics/pdf/PdfDocument.cpp
+++ b/core/jni/android/graphics/pdf/PdfDocument.cpp
@@ -73,11 +73,6 @@ public:
         SkCanvas* canvas = page->mPictureRecorder->beginRecording(
                 contentRect.width(), contentRect.height(), NULL, 0);
 
-        // We pass this canvas to Java where it is used to construct
-        // a Java Canvas object which dereferences the pointer when it
-        // is destroyed, so we have to bump up the reference count.
-        canvas->ref();
-
         return canvas;
     }
 
diff --git a/include/private/graphics/Canvas.h b/include/private/graphics/Canvas.h
index 3cd57f4..2eda6a4 100644
--- a/include/private/graphics/Canvas.h
+++ b/include/private/graphics/Canvas.h
@@ -28,6 +28,16 @@ public:
     virtual ~Canvas() {};
 
     static Canvas* create_canvas(SkBitmap* bitmap);
+
+    /**
+     *  Create a new Canvas object which delegates to an SkCanvas.
+     *
+     *  @param skiaCanvas Must not be NULL. All drawing calls will be
+     *      delegated to this object. This function will call ref() on the
+     *      SkCanvas, and the returned Canvas will unref() it upon
+     *      destruction.
+     *  @return new Canvas object. Will not return NULL.
+     */
     static Canvas* create_canvas(SkCanvas* skiaCanvas);
 
     // TODO: enable HWUI to either create similar canvas wrapper or subclass