在UIBotton中移除CAGradientLayer渐变色图层

1.设置渐变色的代码，代码中一定要加上gradient.name = @"gradientLayer";

CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame =CGRectMake(0, 0, btn.frame.size.width, btn.frame.size.height);
gradient.name = @"gradientLayer";
gradient.colors = [NSArray arrayWithObjects:
(id)HexColor(@"#1892BF").CGColor,
(id)HexColor(@"#2EAA7B").CGColor,
nil];
[btn.layer insertSublayer:gradient atIndex:0];//插入layer

2.查找渐变色图层，根据上文赋值给layer的“name”进行查找

for (CALayer *layer in [btn.layer.sublayers copy]){
    if ([[layer name] isEqualToString:@"gradientLayer"]) {
        NSLog(@"Gradient layer found.");
    }
}

3.对找到的图层进行移除，再if里面加上[layer removeFromSuperlayer];

示例：

for (CALayer *layer in [btn.layer.sublayers copy]){
    if ([[layer name] isEqualToString:@"gradientLayer"]) {
        NSLog(@"Gradient layer found.");
        [layer removeFromSuperlayer];//删除layer
    }
}