Question

Is there a way to Pan a grid view to Horizontal Direction. I am implementing a grid view on a image. So whenever I zoom the image grid should also get to be zoom and pan in all direction, so i can select a specific area of the image.

I googled for panning of grid but not got satisfactory answers. please help me with some example code.

Answer 1

I too searched for some standard methods for zooming views other than image views but didn’t find anything. So, I did a workaround for this and it works.
For zooming a view you can apply zoom animation on the view with fillAfter property enabled.

Here is how you can do this:

    ScaleAnimation scale;
    final float MAX_SCALE_FACTOR = 5f;
    float currentScaleFactor = 1;
    public static final long DURATION = 500;

    GridView grid = (GridView)findViewById(R.id.grid);


    public void scaleMyView()
    {
        if(currentScaleFactor <= MAX_SCALE_FACTOR)
        {
             DecelerateInterpolator interpolator = new  DecelerateInterpolator();
             scale = new ScaleAnimation(currentScaleFactor, currentScaleFactor*1.2f, 
                            currentScaleFactor, currentScaleFactor*1.2f);
             currentScaleFactor *= 1.2;
             scale.setDuration(DURATION);
             scale.setInterpolator(interpolator);
             scale.setFillEnabled(true);
             scale.setFillAfter(true);

             grid.startAnimation(scale);
       }
  }

Here each time this method is called the view is scaled and the dimension is saved. You can decrease the animation duration to give the effect of instant zooming. Now you can call this method onPan or onTouch to apply zoom.

I hope this will help.