/**
     * 字体颜色渐变
     * @param textView
     */
    private void setTextViewStyles(TextView textView) {
        float x1=textView.getPaint().measureText(textView.getText().toString());//测量文本 宽度
        float y1=textView.getPaint().getTextSize();//测量文本 高度
        int c1=Color.RED;//初始颜色值
        int c2= Color.BLUE;//结束颜色值

        LinearGradient leftToRightLG = new LinearGradient(0, 0, x1, 0,c1, c2, Shader.TileMode.CLAMP);//从左到右渐变
        LinearGradient topToBottomLG = new LinearGradient(0, 0, 0, y1,c1, c2, Shader.TileMode.CLAMP);//从上到下渐变

        textView.getPaint().setShader(leftToRightLG);
        textView.invalidate();
    }