如何使用线性渐变填充Android中的路径？

Question

给定一个封闭的Path对象结果是这样的:

虽然这是一个矩形我正在寻找适用于任何封闭路径的东西.

Answer 1

虽然steelbytes的答案可能会让你更多地控制渐变的各个部分,但你可以在没有路径的情况下完成:

protected void onDraw(Canvas canvas)
{
    super.onDraw(canvas);
    Paint p = new Paint();
    // start at 0,0 and go to 0,max to use a vertical
    // gradient the full height of the screen.
    p.setShader(new LinearGradient(0, 0, 0, getHeight(), Color.BLACK, Color.WHITE, Shader.TileMode.MIRROR));
    canvas.drawPaint(p);
}

Answer 2

这可能有所帮助

protected void onDraw(Canvas canvas)
{
    super.onDraw(canvas);
    int w = getWidth();
    int h = getHeight();
    Paint p = new Paint(Paint.ANTI_ALIAS_FLAG|Paint.FILTER_BITMAP_FLAG);
    Path pth = new Path();
    pth.moveTo(w*0.27f,0);
    pth.lineTo(w*0.73f,0);
    pth.lineTo(w*0.92f,h);
    pth.lineTo(w*0.08f,h);
    pth.lineTo(w*0.27f,0);
    p.setColor(0xff800000);
    p.setShader(new LinearGradient(0,0,0,h,0xff000000,0xffffffff,Shader.TileMode.CLAMP));
    canvas.drawPath(pth,p);
}