title: Set maximum and minimum zooming levels for image
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/9357090/imageview-issue-with-zoom-in-and-out-drag-with-maximum-and-minimum-levels">Imageview issue with zoom in and out,drag with maximum and minimum levels</a>  </p>
  </blockquote>
  
  
  
  <p>I have image zooming and dragging in my application. My requirement is the image sets maximum and minimum zooming levels. I have used the below code.</p>
  
  <pre><code>public class PinchZoomListener implements OnTouchListener {
  
      private static final String TAG = "Touch";
      // These matrices will be used to move and zoom image
      Matrix matrix = new Matrix();
      Matrix savedMatrix = new Matrix();
  
      // We can be in one of these 3 states
      static final int NONE = 0;
      static final int DRAG = 1;
      static final int ZOOM = 2;
      int mode = NONE;
  
      // Remember some things for zooming
      PointF start = new PointF();
      PointF mid = new PointF();
      float oldDist = 1f;
  
      public boolean onTouch(View v, MotionEvent event) {
          ImageView view = (ImageView) v;
          dumpEvent(event);// Dump touch event to log
  
          switch (event.getAction() &amp; MotionEvent.ACTION_MASK) {
          case MotionEvent.ACTION_DOWN:
              savedMatrix.set(matrix);
              start.set(event.getX(), event.getY());
              Log.d(TAG, "mode=DRAG");
              mode = DRAG;
              break;
          case MotionEvent.ACTION_POINTER_DOWN:
              oldDist = spacing(event);
              Log.d(TAG, "oldDist=" + oldDist);
              if (oldDist &gt; 10f) {
                  savedMatrix.set(matrix);
                  midPoint(mid, event);
                  mode = ZOOM;
                  Log.d(TAG, "mode=ZOOM");
              }
              break;
          case MotionEvent.ACTION_UP:
          case MotionEvent.ACTION_POINTER_UP:
              mode = NONE;
              Log.d(TAG, "mode=NONE");
              break;
          case MotionEvent.ACTION_MOVE:
              if (mode == DRAG) {
                  // ...
                  matrix.set(savedMatrix);
                  matrix.postTranslate(event.getX() - start.x, event.getY() - start.y);
              } else if (mode == ZOOM) {
                  float newDist = spacing(event);
                  Log.d(TAG, "newDist=" + newDist);
                  if (newDist &gt; 10f) {
                      matrix.set(savedMatrix);
                      float scale = newDist / oldDist;
                      matrix.postScale(scale, scale, mid.x, mid.y);
                  }
              }
              break;
          }
          view.setImageMatrix(matrix);
          return true; // indicate event was handled
      }
  
      /** Show an event in the LogCat view, for debugging */
      private void dumpEvent(MotionEvent event) {
          String names[] = { "DOWN", "UP", "MOVE", "CANCEL", "OUTSIDE", "POINTER_DOWN", "POINTER_UP", "7?", "8?", "9?" };
          StringBuilder sb = new StringBuilder();
          int action = event.getAction();
          int actionCode = action &amp; MotionEvent.ACTION_MASK;
          sb.append("event ACTION_").append(names[actionCode]);
          if (actionCode == MotionEvent.ACTION_POINTER_DOWN || actionCode == MotionEvent.ACTION_POINTER_UP) {
              sb.append("(pid ").append(action &gt;&gt; MotionEvent.ACTION_POINTER_ID_SHIFT);
              sb.append(")");
          }
          sb.append("[");
          for (int i = 0; i &lt; event.getPointerCount(); i++) {
              sb.append("#").append(i);
              sb.append("(pid ").append(event.getPointerId(i));
              sb.append(")=").append((int) event.getX(i));
              sb.append(",").append((int) event.getY(i));
              if (i + 1 &lt; event.getPointerCount())
                  sb.append(";");
          }
          sb.append("]");
          Log.d(TAG, sb.toString());
      }
  
      /** Determine the space between the first two fingers */
      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);
      }
  
      /** Calculate the mid point of the first 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>How can I set maximum and minimum zooming levels for image in Android?</p>