Android VideoRendererGui: Add dispose function

talk/app/webrtc/java/android/org/webrtc/VideoRendererGui.java

Index: talk/app/webrtc/java/android/org/webrtc/VideoRendererGui.java
diff --git a/talk/app/webrtc/java/android/org/webrtc/VideoRendererGui.java b/talk/app/webrtc/java/android/org/webrtc/VideoRendererGui.java
index 0c910f14c7b4a51456d4ed98cd8ec53b2e3fa570..c2eccce36743391d291b38e65d17b4c93953c1b3 100644
--- a/talk/app/webrtc/java/android/org/webrtc/VideoRendererGui.java
+++ b/talk/app/webrtc/java/android/org/webrtc/VideoRendererGui.java
@@ -101,6 +101,24 @@ public class VideoRendererGui implements GLSurfaceView.Renderer {
     yuvImageRenderers = new ArrayList<YuvImageRenderer>();
   }
 
+  public static void dispose() {

[AlexG, 2015/08/05 18:19:23]

May be better to declare this method as synchronized (will be synchronized on
class) and remove synchronization on instance, so all instance modifications are
synchronized on class?

[magjed_webrtc, 2015/08/11 10:38:15]

Done.

+    if (instance == null){
+      return;
+    }
+    synchronized (instance) {
+      synchronized (instance.yuvImageRenderers) {
+        for (YuvImageRenderer yuvImageRenderer : instance.yuvImageRenderers) {
+          yuvImageRenderer.release();
+        }
+      }
+      instance.surface = null;
+      if (instance.drawer != null) {
+        instance.drawer.release();
+      }
+      instance = null;
+    }
+  }
+
   /**
    * Class used to display stream of YUV420 frames at particular location
    * on a screen. New video frames are sent to display using renderFrame()
@@ -178,6 +196,16 @@ public class VideoRendererGui implements GLSurfaceView.Renderer {
       rotationDegree = 0;
     }
 
+    private void release() {

[AlexG, 2015/08/05 18:19:23]

synchronized?

[magjed_webrtc, 2015/08/11 10:38:15]

Done.

+      surface = null;
+      if (yuvTextures[0] != -1) {
+        GLES20.glDeleteTextures(3, yuvTextures, 0);
+        for (int i = 0; i < 3; ++i) {
+          yuvTextures[i] = -1;
+        }
+      }
+    }
+
     private void createTextures() {
       Log.d(TAG, "  YuvImageRenderer.createTextures " + id + " on GL thread:" +
           Thread.currentThread().getId());
@@ -425,6 +453,10 @@ public class VideoRendererGui implements GLSurfaceView.Renderer {
 
     @Override
     public synchronized void renderFrame(I420Frame frame) {
+      if (surface == null) {
+        // This object has been released.
+        return;
+      }
       setSize(frame.width, frame.height, frame.rotationDegree);
       long now = System.nanoTime();
       framesReceived++;