Add Pointer capture demo to APIDemos

Bug: 30897034
Test: manually in ApiDemos > Graphics > OpenGL ES > Touch Rotate
Change-Id: Id87b17938cf876b4886de69ffaa8a2b3c4f27143

samples/ApiDemos/src/com/example/android/apis/graphics/TouchRotateActivity.java

@@ -16,9 +16,6 @@
 
 package com.example.android.apis.graphics;
 
-import javax.microedition.khronos.egl.EGLConfig;
-import javax.microedition.khronos.opengles.GL10;
-
 import android.app.Activity;
 import android.content.Context;
 import android.opengl.GLSurfaceView;
@@ -27,6 +24,9 @@ import android.view.InputDevice;
 import android.view.KeyEvent;
 import android.view.MotionEvent;
 
+import javax.microedition.khronos.egl.EGLConfig;
+import javax.microedition.khronos.opengles.GL10;
+
 /**
  * Wrapper activity demonstrating the use of {@link GLSurfaceView}, a view
  * that uses OpenGL drawing into a dedicated surface.
@@ -35,6 +35,9 @@ import android.view.MotionEvent;
  * + How to redraw in response to user input.
  */
 public class TouchRotateActivity extends Activity {
+
+    private GLSurfaceView mGLSurfaceView;
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -63,44 +66,69 @@ public class TouchRotateActivity extends Activity {
         mGLSurfaceView.onPause();
     }
 
-    private GLSurfaceView mGLSurfaceView;
-}
-
     /**
      * Implement a simple rotation control.
      *
      */
-class TouchSurfaceView extends GLSurfaceView {
+    private static class TouchSurfaceView extends GLSurfaceView {
 
-    public TouchSurfaceView(Context context) {
+        private static final float TOUCH_SCALE_FACTOR = 180.0f / 320;
+        private static final float TRACKBALL_SCALE_FACTOR = 36.0f;
+        private CubeRenderer mRenderer;
+        private float mPreviousX;
+        private float mPreviousY;
+
+        TouchSurfaceView(Context context) {
             super(context);
             mRenderer = new CubeRenderer();
             setRenderer(mRenderer);
             setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
         }
 
-    @Override public boolean onTrackballEvent(MotionEvent e) {
+        @Override
-        mRenderer.mAngleX += e.getX() * TRACKBALL_SCALE_FACTOR;
+        public boolean onTrackballEvent(MotionEvent e) {
-        mRenderer.mAngleY += e.getY() * TRACKBALL_SCALE_FACTOR;
+            updateAngles(e.getX(), e.getY(), TRACKBALL_SCALE_FACTOR);
-        requestRender();
             return true;
         }
 
-    @Override public boolean onTouchEvent(MotionEvent e) {
+        @Override
-        if (e.getActionMasked() == MotionEvent.ACTION_MOVE) {
+        public boolean onTouchEvent(MotionEvent e) {
-            updateAngles(e);
+            final int action = e.getActionMasked();
+            if (action == MotionEvent.ACTION_MOVE) {
+                updateAngles(e.getX() - mPreviousX, e.getY() - mPreviousY, TOUCH_SCALE_FACTOR);
+            } else if (action == MotionEvent.ACTION_DOWN) {
+                if (e.isFromSource(InputDevice.SOURCE_MOUSE)) {
+                    requestPointerCapture();
+                } else {
+                    releasePointerCapture();
+                }
             }
             mPreviousX = e.getX();
             mPreviousY = e.getY();
             return true;
         }
 
-    private void updateAngles(MotionEvent e) {
+        @Override
-        float dx = e.getX() - mPreviousX;
+        public boolean onCapturedPointerEvent(MotionEvent e) {
-        float dy = e.getY() - mPreviousY;
+            if (e.getActionMasked() == MotionEvent.ACTION_DOWN) {
+                releasePointerCapture();
+            } else {
+                updateAngles(e.getX(), e.getY(), TOUCH_SCALE_FACTOR);
+            }
+            return true;
+        }
+
+        @Override
+        public boolean onKeyDown(int keyCode, KeyEvent event) {
+            // Release pointer capture on any key press.
+            releasePointerCapture();
+            return super.onKeyDown(keyCode, event);
+        }
+
+        private void updateAngles(float dx, float dy, float scaleFactor) {
             if (dx != 0 && dy != 0) {
-            mRenderer.mAngleX += dx * TOUCH_SCALE_FACTOR;
+                mRenderer.mAngleX += dx * scaleFactor;
-            mRenderer.mAngleY += dy * TOUCH_SCALE_FACTOR;
+                mRenderer.mAngleY += dy * scaleFactor;
                 requestRender();
             }
         }
@@ -108,11 +136,12 @@ class TouchSurfaceView extends GLSurfaceView {
         /**
          * Render a cube.
          */
-    private class CubeRenderer implements GLSurfaceView.Renderer {
+        private static class CubeRenderer implements GLSurfaceView.Renderer {
-        public CubeRenderer() {
+            CubeRenderer() {
                 mCube = new Cube();
             }
 
+            @Override
             public void onDrawFrame(GL10 gl) {
                 /*
                  * Usually, the first thing one might want to do is to clear
@@ -138,6 +167,7 @@ class TouchSurfaceView extends GLSurfaceView {
                 mCube.draw(gl);
             }
 
+            @Override
             public void onSurfaceChanged(GL10 gl, int width, int height) {
                 gl.glViewport(0, 0, width, height);
 
@@ -153,6 +183,7 @@ class TouchSurfaceView extends GLSurfaceView {
                 gl.glFrustumf(-ratio, ratio, -1, 1, 1, 10);
             }
 
+            @Override
             public void onSurfaceCreated(GL10 gl, EGLConfig config) {
                 /*
                  * By default, OpenGL enables features that improve quality
@@ -168,20 +199,14 @@ class TouchSurfaceView extends GLSurfaceView {
                 gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT,
                         GL10.GL_FASTEST);
 
-
                 gl.glClearColor(1, 1, 1, 1);
                 gl.glEnable(GL10.GL_CULL_FACE);
                 gl.glShadeModel(GL10.GL_SMOOTH);
                 gl.glEnable(GL10.GL_DEPTH_TEST);
             }
             private Cube mCube;
-        public float mAngleX;
+            float mAngleX;
-        public float mAngleY;
+            float mAngleY;
+        }
     }
-
-    private final float TOUCH_SCALE_FACTOR = 180.0f / 320;
-    private final float TRACKBALL_SCALE_FACTOR = 36.0f;
-    private CubeRenderer mRenderer;
-    private float mPreviousX;
-    private float mPreviousY;
 }