Android ImageView Zoom-in and Zoom-Out

Question

I want to Zoom-in and Zoom-out an Android ImageView. I tried most of the samples but in all of them the image in the ImageView itself is getting Zoomed-in and Zoomed-out, while I want to Zoom-in and Zoom-out the ImageView. I want to increase the ImageView width and height while Zooming-in and reduce the ImageView width and height while Zooming-out. How do I achieve that?

Answer 1

Make two java classes

Zoom class

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.drawable.Drawable;
import android.view.KeyEvent;
import android.view.View;
import android.widget.Button;
import android.widget.ImageButton;

public class Zoom extends View {

    private Drawable image;
    ImageButton img,img1;
    private int zoomControler=20;

    public Zoom(Context context){
            super(context);

            image=context.getResources().getDrawable(R.drawable.j);
            //image=context.getResources().getDrawable(R.drawable.icon);

            setFocusable(true);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        //here u can control the width and height of the images........ this line is very important
        image.setBounds((getWidth()/2)-zoomControler, (getHeight()/2)-zoomControler, (getWidth()/2)+zoomControler, (getHeight()/2)+zoomControler);
        image.draw(canvas);
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {

            if(keyCode==KeyEvent.KEYCODE_DPAD_UP){
                    // zoom in
                    zoomControler+=10;
            }
            if(keyCode==KeyEvent.KEYCODE_DPAD_DOWN){
                    // zoom out
                    zoomControler-=10;
            }
            if(zoomControler<10){
                    zoomControler=10;
            }

            invalidate();
            return true;
    }
}

make second class

import android.app.Activity;
import android.os.Bundle;

public class Zoomexample extends Activity {
   /** Called when the activity is first created. */

   @Override
   public void onCreate(Bundle icicle) {
       super.onCreate(icicle);
       setContentView(new Zoom(this));
   }
}