Pinch Zoom on Two Views in Single Viewgroup android

Question

I am doing a project in which i need two imageviews in single layout with zooming options. AFAIK android allows one view to make zoom easily. But my problem is not like that. I have two imageviews one over another. I've try to do it in Frame Layout. but the results are not so good. The images are shrink when it goes out of bounds of layout and the zooming is not so smooth. I have tried to do it with the deprecated Absolute layout.but it doesn't work All suggestions are welcomed.

My Code is here

  int x = (int)event.getRawX();
     int y = (int)event.getRawY();
         ImageView view = (ImageView) v;

         switch (event.getAction() & MotionEvent.ACTION_MASK) {
          case MotionEvent.ACTION_DOWN:
             savedMatrix.set(matrix);
             start.set(event.getX(), event.getY());

             mode = DRAG;
           hoffset = x - v.getLeft();
       voffset = y - v.getTop();
             break;
          case MotionEvent.ACTION_POINTER_DOWN:
             oldDist = spacing(event);
             Log.d(TAG, "oldDist=" + oldDist);
             if (oldDist > 10f) {
                savedMatrix.set(matrix);
                midPoint(mid, event);
                mode = ZOOM;
                Log.d(TAG, "mode=ZOOM");
             }
             break;
          case MotionEvent.ACTION_UP:
            // moveView(v, x - hoffset, y - voffset);
          case MotionEvent.ACTION_POINTER_UP:
             mode = NONE;

             Log.d(TAG, "mode=NONE");
             break;
          case MotionEvent.ACTION_MOVE:
             if (mode == DRAG) {
                 moveView(v, x - hoffset, y - voffset);
                hrecent = x;
                vrecent = y;
             }
             else if (mode == ZOOM) {


                newDist = spacing(event);
                if (newDist > 10f) {

                   matrix.set(savedMatrix);

                   float scale = newDist / oldDist;
         matrix.postScale(ScaleFactorForZoom, ScaleFactorForZoom, mid.x, mid.y);



               float delta =10.0f+ (newDist -oldDist)/oldDist;
           // view.setImageMatrix(matrix);    
                 float newHeight;
                 float newWidth;


        newHeight=(float) ((delta)+view.getHeight());
        newWidth=(float) ((delta)+view.getWidth());

                    oldDist = newDist; 



                 zoomView(view, newWidth, newHeight);

                }
             }
             break;
          }



          return true; 
    }

The MoveView Function is

     public void moveView(View v, int x, int y)
       {
         ViewGroup.LayoutParams params = v.getLayoutParams();
         if (params instanceof FrameLayout.LayoutParams)
         {
           FrameLayout.LayoutParams par = (FrameLayout.LayoutParams)params;
          View parent = (View)(v.getParent());
           x = Math.min(x, parent.getWidth());
           x = Math.max(x, 0);
           y = Math.min(y, parent.getHeight());
           y = Math.max(y, 0);


          par.leftMargin=x;
          par.topMargin=y;
           v.setLayoutParams(par);
       }
   }

The Zoom Function is here

public void zoomView(View v, float width, float height)
   {
       ViewGroup.LayoutParams params = v.getLayoutParams();
       if (params instanceof FrameLayout.LayoutParams)
       {
           FrameLayout.LayoutParams par = (FrameLayout.LayoutParams)params;
           par.width = (int)width;
           par.height = (int)height;

           v.setLayoutParams(par);


       }
   }

Answer 1

I did it by placing two image views above Frame Layout and write touch event for Frame Layout and put two buttons for choosing the view to zoom and set matrix for that image

Answer 2

You should not use par.width = (int) width because the fractional part is truncated by a fault always by default, instead uses par.width = Math.round (Width) and think of a mechanism to restore the default values ​​sometimes.