Question

In Android, how to give draw a rotating/flipping coin wrt user on SurfaceView. It’s very easy to use an animation and show the flipping coin in an ImageView, but I require this on SurfaceView with the same smoothness. Is there any way that I can give flipping animation in an ImageView then take out its content at every instant and then draw it on the SurfaceView continuously?

Answer 1

you can use Matrix class to perfom these operation on drawing bitmap.

something like

Paint paint = new Paint();
    paint.setAntiAlias(true);
    Matrix needleTransMatrix = new Matrix();
    needleTransMatrix.postRotate(rotationAngle,needleImage.getWidth()/2,needleImage.getHeight());
    needleTransMatrix.postTranslate( centerX+METER_OFFSET-needleImage.getWidth()/2, centerY-needleImage.getHeight());

    Matrix dialTransMatrix = new Matrix();
    dialTransMatrix.postRotate(rotationAngle,dialImage.getWidth()/2,dialImage.getHeight()/2);
    dialTransMatrix.postTranslate( METER_OFFSET,0);

    canvas.drawBitmap(bgImage, METER_OFFSET, 0, paint);
    canvas.drawBitmap(dialImage, dialTransMatrix, paint);
    canvas.drawBitmap(needleImage, needleTransMatrix, paint);

The below is the drawing thread about which i am talking about

private class AnimationThread extends Thread{

    private boolean isRunning = true;
    private int destinationNeedlePosition = NEEDLE_POSITION_ENQURIES;

    public AnimationThread(int destinationNeedlePosition) {
        this.destinationNeedlePosition = destinationNeedlePosition;
    }

    public void cancelAnimation(){
        isRunning = false;
    }

    @Override
    public void run() {

        int destinationAngle = destinationNeedlePosition *45;

        while(isRunning && destinationAngle != rotationAngle){
            if(destinationAngle > rotationAngle)
                rotationAngle++;
            else
                rotationAngle--;
            postInvalidate();
            try {
                sleep(10);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

}