ColorSquare.java 文件源码

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);

    if(paint==null)
    {
        paint = new Paint();
        lg = new LinearGradient(0.0f, 0.0f, 0.0f, this.getMeasuredHeight(), 0xffffffff, 0xff000000,  TileMode.CLAMP);
    }

    if(updateColor){
        int rgb = Color.HSVToColor(color);
        lg2 = new LinearGradient(0.0f, 0.0f, this.getMeasuredWidth(), 0.0f, 0xffffffff, rgb, TileMode.CLAMP);
        shader = new ComposeShader(lg, lg2, PorterDuff.Mode.MULTIPLY);
        updateColor = false;
    }

    paint.setShader(shader);
    canvas.drawRect(0.0f, 0.0f, this.getMeasuredWidth(), this.getMeasuredHeight(), paint);
}