在缩放或拖动（左，右，上，下）图像时，如何设置另一个视图的精确位置？

Question

I met a big trouble in this case. I have a imageview (green icon) added on Image background. Green icon's position is set dynamically(Pic 1)

This Image can zoom in, zoom out, drag left, right, up, down. I want to to move exactly imageview's position (green icon) when zoom or drag image background.

How can I map imageview's position (green icon) with Image background when I zoom, drag Image background?

Picture 2: Image background is zoomed but green icon view does not map with image background, it's wrong position.

Can you suggest me some solution, direction or scripts. Thanks all!

Answer 1

use following function which will overlay your image bitmap with mark image bitmap and return new bitmap which you can use to display

private Bitmap overlay(Bitmap bmp1, Bitmap bmp2, float left, float top) {
        Bitmap bmOverlay = Bitmap.createBitmap(bmp1.getWidth(), bmp1.getHeight(), bmp1.getConfig());
        Canvas canvas = new Canvas(bmOverlay);
        canvas.drawBitmap(bmp1, new Matrix(), null);
        canvas.drawBitmap(bmp2, left, top, null); 
        return bmOverlay;
    }

eg :-

        Bitmap border = null;
        Bitmap scaledBorder = null;
        border = BitmapFactory.decodeResource(getResources(), R.drawable.palette);
        scaledBorder = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
        ImageView im = (ImageView) findViewById(R.id.imageView);
        im.setImageBitmap(overlay(border, scaledBorder, 0, 0));// replace both 0,0 point with your mark point