title: Android: How to perform zoom on two imageviews in android?
body: <p>I have two images inside my layout. I need to zoom that image which i touched. We know that Frame can display a single view at a time. So how do i perform zoom on each imageview separately ? My xml file :</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  
  &lt;FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent" &gt;
  
  &lt;ImageView
      android:id="@+id/imageView1"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent"
      android:gravity="center"
    android:src="@drawable/image1" /&gt;
  
    &lt;ImageView
      android:id="@+id/imageView2"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent"
      android:gravity="center"   android:src="@drawable/image2"
  
    /&gt;
  
  &lt;/FrameLayout&gt;
  </code></pre>
  
  <p>Activity file : </p>
  
  <pre><code>public class MyActivity extends Activity implements OnTouchListener
  {
  private static final String TAG = "Touch";
  
  // These matrices will be used to scale points of the image
  Matrix matrix = new Matrix();
  Matrix savedMatrix = new Matrix();
  
  // The 3 states (events) which the user is trying to perform
  static final int NONE = 0;
  static final int DRAG = 1;
  static final int ZOOM = 2;
  int mode = NONE;
  
  // these PointF objects are used to record the point(s) the user is touching
  PointF start = new PointF();
  PointF mid = new PointF();
  float oldDist = 1f;
  
  private ImageView iv1;
  private ImageView iv2;
  @Override
  protected void onCreate(Bundle savedInstanceState) {
  
      super.onCreate(savedInstanceState);
  
      setContentView(R.layout.main);
  
  
      iv1 = ((ImageView)findViewById(R.id.imageView1));
      iv1.setOnTouchListener(this);
  
  
      iv2 = ((ImageView)findViewById(R.id.imageView2));
      iv2.setOnTouchListener(this);
  
  
  
  }
  @Override
  public boolean onTouch(View v, MotionEvent event) {
      switch (v.getId()) {
      case R.id.imageView1:
          zoomImageView(v, event);
          break;
      case R.id.imageView2:
          zoomImageView(v, event);
          break;
  
      default:
          break;
      }
      return true;
  }
  private boolean zoomImageView(View v, MotionEvent event) {
  
  
      ImageView view = (ImageView) v;
      view.setScaleType(ImageView.ScaleType.MATRIX);
      float scale;
  
  
      switch (event.getAction() &amp; 255) 
      {
      case MotionEvent.ACTION_DOWN:   // first finger down only
          savedMatrix.set(matrix);
          start.set(event.getX(), event.getY());
          Log.d(TAG, "mode=DRAG"); // write to LogCat
          mode = DRAG;
          break;
  
      case MotionEvent.ACTION_UP: // first finger lifted
  
      case 6: // second finger lifted
  
          mode = NONE;
          Log.d(TAG, "mode=NONE");
          break;
  
      case 5: // first and second finger down
  
          oldDist = spacing(event);
          Log.d(TAG, "oldDist=" + oldDist);
          if (oldDist &gt; 5f) {
              savedMatrix.set(matrix);
              midPoint(mid, event);
              mode = ZOOM;
              Log.d(TAG, "mode=ZOOM");
          }
          break;
  
      case MotionEvent.ACTION_MOVE:
  
          if (mode == DRAG) 
          { 
              matrix.set(savedMatrix);
              matrix.postTranslate(event.getX() - start.x, event.getY() - start.y); // create the transformation in the matrix  of points
          } 
          else if (mode == ZOOM) 
          { 
              // pinch zooming
              float newDist = spacing(event);
              Log.d(TAG, "newDist=" + newDist);
              if (newDist &gt; 5f) 
              {
                  matrix.set(savedMatrix);
                  scale = newDist / oldDist; // setting the scaling of the
                  // matrix...if scale &gt; 1 means
                  // zoom in...if scale &lt; 1 means
                  // zoom out
                  matrix.postScale(scale, scale, mid.x, mid.y);
              }
          }
          break;
      }
  
      view.setImageMatrix(matrix); // display the transformation on screen
  
      return true; // indicate event was handled
  
  }
  private float spacing(MotionEvent event) 
  {
      float x = event.getX(0) - event.getX(1);
      float y = event.getY(0) - event.getY(1);
      return FloatMath.sqrt(x * x + y * y);
  }
  
  /*
   * --------------------------------------------------------------------------
   * Method: midPoint Parameters: PointF object, MotionEvent Returns: void
   * Description: calculates the midpoint between the two fingers
   * ------------------------------------------------------------
   */
  
  private void midPoint(PointF point, MotionEvent event) 
  {
      float x = event.getX(0) + event.getX(1);
      float y = event.getY(0) + event.getY(1);
      point.set(x / 2, y / 2);
  }
   }
  </code></pre>
  
  <p>Now i'am able zoom only image1 which is on top. How do i get the zoom functionality for  bottom image on touch of image2 ? I should be able to zoom the image on which i touched.   Please help me.</p>