Implement touch control

platform_tools/android/apps/viewer/src/main/java/org/skia/viewer/ViewerActivity.java

Index: platform_tools/android/apps/viewer/src/main/java/org/skia/viewer/ViewerActivity.java
diff --git a/platform_tools/android/apps/viewer/src/main/java/org/skia/viewer/ViewerActivity.java b/platform_tools/android/apps/viewer/src/main/java/org/skia/viewer/ViewerActivity.java
index d6fe710aeb0fa8fa0f8a3b9daf2f8f11886de67b..49f711d517171556670b14cd8432a3cff7a2e474 100644
--- a/platform_tools/android/apps/viewer/src/main/java/org/skia/viewer/ViewerActivity.java
+++ b/platform_tools/android/apps/viewer/src/main/java/org/skia/viewer/ViewerActivity.java
@@ -32,6 +32,7 @@ public class ViewerActivity
     private native void onSurfaceChanged(long handle, Surface surface);
     private native void onSurfaceDestroyed(long handle);
     private native void onKeyPressed(long handle, int keycode);
+    private native void onTouched(long handle, int owner, int state, float x, float y);
 
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
@@ -96,6 +97,14 @@ public class ViewerActivity
 
     @Override
     public boolean onTouch(View v, MotionEvent event) {
-        return false; // TODO pass the touch event to native code
+        int count = event.getPointerCount();
+        for (int i = 0; i < count; i++) {
+            final float x = event.getX(i);
+            final float y = event.getY(i);
+            final int owner = event.getPointerId(i);
+            int action = event.getAction() & MotionEvent.ACTION_MASK;
+            onTouched(mApplication.getNativeHandle(), owner, action, x, y);
+        }
+        return true;
     }
 }