我正在使用 CAGradientLayer 来设置我的 uibuttons 样式。基本上在一个单元格中有三个按钮。当我首先设置 CAGradientLayer 属性时，它工作正常（我得到一个渐变）。
但是，当我将 CAGradientLayer 应用于第二个时，它确实出现在第二个上，但从第一个上消失了。如果我在第三个上做，那么它会出现在第三个上，然后从前两个上消失。
我应该在 UIButton 设置之间释放 CAGradientLayer 吗？
这是一些示例代码：
//like button
self.likeButton=[[UIButton alloc] initWithFrame:CGRectMake(10, 430, 80, 26)];
[self.likeButton.titleLabel setFont:[UIFont boldSystemFontOfSize:12]];
[self.likeButton.titleLabel setTextAlignment:NSTextAlignmentLeft];
self.likeButton.tag=indexPath.row;
[self.likeButton addTarget:self action:@selector(likeButtonPressed:) forControlEvents:UIControlEventTouchUpInside];
[self.likeButton setBackgroundColor:[UIColor blackColor]];
[self.likeButton setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
[self.likeButton setTitleColor:[UIColor greenColor] forState:UIControlStateHighlighted];
CAGradientLayer *btnGradient=[CAGradientLayer layer];
btnGradient.frame=self.likeButton.bounds;
btnGradient.colors=[NSArray arrayWithObjects:(id)[[UIColor colorWithRed:102.0f / 255.0f green:102.0f / 255.0f blue:102.0f / 255.0f alpha:1.0f] CGColor], (id)[[UIColor colorWithRed:41.0f / 255.0f green:41.0f / 255.0f blue:41.0f / 255.0f alpha:1.0f]CGColor], nil];
[self.likeButton.layer insertSublayer:btnGradient atIndex:0];
CALayer *btnLayer=self.likeButton.layer;
[btnLayer setMasksToBounds:YES];
[btnLayer setCornerRadius:5.0f];
[btnLayer setBorderWidth:1.0f];
[btnLayer setBorderColor:[[UIColor darkGrayColor]CGColor]];
[cell addSubview:self.likeButton];
//comment button
UIButton *commentButton=[[UIButton alloc]initWithFrame:CGRectMake(110, 430, 80, 26)];
[commentButton.titleLabel setFont:[UIFont boldSystemFontOfSize:12]];
[commentButton.titleLabel setTextAlignment:NSTextAlignmentLeft];
[commentButton setBackgroundColor:[UIColor blackColor]];
[commentButton setTitle:@"Comment" forState:UIControlStateNormal];
[commentButton addTarget:self action:@selector(commentButtonPressed:) forControlEvents:UIControlEventTouchUpInside];
[commentButton setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
[commentButton setTitleColor:[UIColor greenColor] forState:UIControlStateHighlighted];
CAGradientLayer *commentBGLayer=[CAGradientLayer layer];
commentBGLayer.frame=commentButton.bounds;
commentBGLayer.colors=[NSArray arrayWithObjects:(id)[[UIColor colorWithRed:102.0f / 255.0f green:102.0f / 255.0f blue:102.0f / 255.0f alpha:1.0f] CGColor], (id)[[UIColor colorWithRed:41.0f / 255.0f green:41.0f / 255.0f blue:41.0f / 255.0f alpha:1.0f]CGColor], nil];
[commentButton.layer insertSublayer:btnGradient atIndex:0];
CALayer *commentBLayer=commentButton.layer;
[commentBLayer setMasksToBounds:YES];
[commentBLayer setCornerRadius:5.0f];
[commentBLayer setBorderWidth:1.0f];
[commentBLayer setBorderColor:[[UIColor darkGrayColor]CGColor]];
[cell addSubview:commentButton];