gistfile1.java

public class ColorGradientCircleButton extends View{
	
	private Paint mPaint;
    private int width, height;

	public ColorGradientCircleButton(Context context) {
		super(context);
		init();
	}
	public ColorGradientCircleButton(Context context, AttributeSet attrs) {
		super(context, attrs);
		init();
	}
	public ColorGradientCircleButton(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		init();
	}
	private void init() {		
		mPaint = new Paint();
		mPaint.setColor(Color.BLACK);
		mPaint.setStrokeWidth(1);
		mPaint.setStyle(Paint.Style.FILL_AND_STROKE);
	}
	@Override
	protected void onDraw(Canvas canvas) {
		super.onDraw(canvas);
		width = getWidth();
		height = getHeight();
		canvas.drawCircle(width/2, height/2, height/3, mPaint);
	}
	public void changeColor(int color){
		mPaint.setColor(color);
		invalidate();
	}
}