java - Cannot draw updated Canvas to Activity

Question

We're trying to code a small clone of 2048 for Android. We have activity where we draw the tiles on top of the background grid. Initially we set up the Bitmap (background) and the Canvas (gameCanvas) in our Activity like this:

ImageView canvasBackgroundImage = findViewById(R.id.imageCanvas);
background = BitmapFactory.decodeResource(getResources(), R.drawable.grid4x4_background).copy(Bitmap.Config.ARGB_8888, true);
canvasBackgroundImage.setImageBitmap(background);
gameCanvas = new Canvas(background);
canvasHandler = new CanvasHandler(gameCanvas);
gameCanvas = canvasHandler.drawGridToCanvas(gameGrid,background);

Then, after every game move, we want our canvasHandler to pass us the new canvas with the new game state so and draw that to the screen (gameGrid being the state of the game).

private void updateCanvas() {
        gameCanvas = canvasHandler.drawGridToCanvas(gameGrid,background);
}

This doesn't work. We tried view.invalidate() but that also wouldn't work.

This is the drawGridToCanvas() method in CanvasHandler:

public Canvas drawGridToCanvas(Grid grid, Bitmap background) {
        canvas = new Canvas(background);
        drawTileAtLocation(2,3);
        //dummy method
        return canvas;
}

question from:https://stackoverflow.com/questions/65858028/cannot-draw-updated-canvas-to-activity

Answer 1

Waitting for answers