Question

Currently I am writing a program that is supposed to add an image to a canvas and then add that canvas to a relative layout. The problem that I am having is that when I call this the layout is displayed but the canvas is not drawn on the layout.

canvas = (RelativeLayout) findViewById(R.id.canvasLayout);                  
imageCanvas = new Canvas();
mainImage = BitmapFactory.decodeResource(getResources(), R.drawable.image);

imageCanvas.drawBitmap(mainImage, 50, 50, null);

imageCanvas.drawColor(Color.BLACK);
canvas.draw(imageCanvas);

That is the code that is attempting to add the image to the canvas and then the canvas to the layout.

I am completely lost as to what to do to attempt to fix this.

Answer 1

The following will programmatically add an image to your layout from a bitmap resource which sounds like what you want to do. If you need to draw on top of that image, say, you would need to make a custom component by extending ImageView and overriding onDraw().

canvas = (RelativeLayout) findViewById(R.id.canvasLayout);                  
imageView = new ImageView(getApplicationContext());
mainImage = BitmapFactory.decodeResource(getResources(), R.drawable.image);
imageView.setImageBitmap( mainImage );
canvas.addView( imageView );