Help with Canvas.DrawBitmap() !!!

Hello, Im getting started with this.....

I´m cretaing a videogame, aand im trying to draw something, before i could do it, but now i cant......

i put something like this....

canvas.drawBitmap(BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher), null, new Rect(0,0,100,100), null);

but it doesnt draw it

playing with numbers in the Rects i obtained some extrange results, like the half of the image drawed .... and its very wear.

Can you help me??? i have tried many ways and i need this.....

Thanks