title: setXfermode(new PorterDuffXfermode(Mode.SRC_OUT)) is giving error
body: <p>I have two images, one above one and i want to make the upper image transparent when user erase it and covered image should be shown...hear is my code </p>
  
  <pre><code>import android.app.Activity;
  import android.content.Context;
  import android.graphics.Bitmap;
  import android.graphics.Bitmap.Config;
  import android.graphics.BlurMaskFilter.Blur;
  import android.graphics.BitmapFactory;
  import android.graphics.BlurMaskFilter; 
  import android.graphics.Canvas;
  import android.graphics.Color;
  import android.graphics.Paint;
  import android.graphics.PorterDuff.Mode;
  import android.graphics.PorterDuffXfermode;
  import android.os.Bundle;
  import android.view.MotionEvent;
  import android.view.View;
  
  public class StartActivity extends Activity {
  
      @Override
      public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(new TouchView(this));
      }
  
      class TouchView extends View{
          Bitmap bgr;
          Bitmap overlayDefault;
          Bitmap overlay;
          Paint pTouch;
          int X = -100;
          int Y = -100;
          Canvas c2;
  
          public TouchView(Context context) {
              super(context);
  
              bgr = BitmapFactory.decodeResource(getResources(),R.drawable.bgr);
              overlayDefault = BitmapFactory.decodeResource(getResources(),R.drawable.over);
              overlay = BitmapFactory.decodeResource(getResources(),R.drawable.over).copy(Config.ARGB_8888, true);  
              c2 = new Canvas(overlay);
  
              pTouch = new Paint(Paint.ANTI_ALIAS_FLAG);         
              pTouch.setXfermode(new PorterDuffXfermode(Mode.SRC_OUT)); 
              pTouch.setColor(Color.TRANSPARENT);
              pTouch.setMaskFilter(new BlurMaskFilter(15, Blur.NORMAL));
          }
  
          @Override
          public boolean onTouchEvent(MotionEvent ev) {
  
              switch (ev.getAction()) {
  
                  case MotionEvent.ACTION_DOWN: {
                      X = (int) ev.getX();
                      Y = (int) ev.getY();
                      invalidate();
                      break;
                  }
  
                  case MotionEvent.ACTION_MOVE: {
                      X = (int) ev.getX();
                      Y = (int) ev.getY();
                      invalidate();
                      break;
                  }           
  
                  case MotionEvent.ACTION_UP: {
                      break;
                  }
              }
              return true;
          }
  
          @Override
          public void onDraw(Canvas canvas) {
              super.onDraw(canvas);
  
              //draw background
              canvas.drawBitmap(bgr, 0, 0, null);
              //copy the default overlay into temporary overlay and punch a hole in it                          
              c2.drawBitmap(overlayDefault, 0, 0, null); //exclude this line to show all as you draw
              c2.drawCircle(X, Y, 80, pTouch);
              //draw the overlay over the background  
              canvas.drawBitmap(overlay, 0, 0, null);
          }
      }
  }
  </code></pre>
  
  <p>But I am getting error at line:</p>
  
  <blockquote>
    <p>pTouch.setXfermode(new PorterDuffXfermode(Mode.SRC_OUT));</p>
  </blockquote>
  
  <p>The error is:</p>
  
  <blockquote>
    <p>"SRC_OUT cannot be resolved or is not a field".</p>
  </blockquote>