ColorHueSlider.java 文件源码

@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    super.onSizeChanged(w, h, oldw, oldh);

    LinearGradient gradient =
            new LinearGradient(0.0f, 0.0f, ((float) getWidth()), 0.0f,
                    new int[]{0xFF000000, 0xFF0000FF, 0xFF00FF00, 0xFF00FFFF,
                            0xFFFF0000, 0xFFFF00FF, 0xFFFFFF00, 0xFFFFFFFF},
                    null, Shader.TileMode.CLAMP);
    ShapeDrawable shape = new ShapeDrawable(new RectShape());
    shape.getPaint().setShader(gradient);

    Rect bounds = getProgressDrawable().getBounds();
    setProgressDrawable(shape);
    getProgressDrawable().setBounds(bounds);
}