drawImage Java api

drawImage(Image img, int x, int y, Color bgcolor, ImageObserver observer)

I would like to specify a null colour for bg colour in the above m开发者_如何学编程ethod. It defaults to black. I thought I could specify null as argument for bgcolor but it doesn't work. Any ideas?

I'm using

drawImage(img, 0, 0, null, this);

It works, but just draws black when I want no colour.

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Why do you want to specify null as a colour; what is your goal? Do you want the background to be transparent instead of black?

When this is what you want, try using a colour that has alpha set to 0 (fully transparent):

Color transparent = new Color(0, 0, 0, 0);
graphics.drawImage(img, 0, 0, transparent, this);