ios 给view添加一个渐变的背景色

CAGradientLayer *gradientLayer = [[CAGradientLayer alloc] init];

    gradientLayer.colors = @[(__bridge id)mRGBToColor(0xff8800).CGColor,(__bridge id)mRGBToColor(0xff5100).CGColor];

　　//位置x,y    自己根据需求进行设置   使其从不同位置进行渐变

    gradientLayer.startPoint = CGPointMake(1, 0);

    gradientLayer.endPoint = CGPointMake(1, 1);

    gradientLayer.frame = CGRectMake(0, 0, CGRectGetWidth(self.backView.frame), CGRectGetHeight(self.backView.frame));

    [self.backView.layer addSublayer:gradientLayer];