看一下下图：
正如您所看到的那样,边缘是尖锐的矩形,它们是从圆角按钮出来的.我怎么能不显示边缘,只显示圆形按钮？
更新(解决方案)：
我使用以下代码来实现圆角：
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:self.stopButton.bounds
byRoundingCorners:UIRectCornerAllCorners
cornerRadii:CGSizeMake(12.0,12.0)];
// Create the shape layer and set its path
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame = self.stopButton.bounds;
maskLayer.path = maskPath.CGPath;
// Set the newly created shape layer as the mask for the image view's layer
self.stopButton.layer.mask = maskLayer;
新问题：
这段代码给了我startButtonRound.layer.cornerRadius行的错误.
UIButton *roundStartButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
roundStartButton.frame = CGRectMake(10,10,100,20);
[roundStartButton setBackgroundImage:[UIImage imageNamed:@"green_gradient.jpg"] forState:UIControlStateNormal];
roundStartButton.layer.cornerRadius = 12.0;
UIBarButtonItem *startButton = [[UIBarButtonItem alloc] initWithCustomView:roundStartButton];
解决方法
你可以单独用CALayer做到这一点：
CALayer *myLayer = [CALayer layer]; [myLayer setMasksToBounds:YES]; [myLayer setCornerRadius:5.0f]; [myLayer setBorderWidth:1.0f]; [myLayer setBorderColor: [[UIColor blackColor] CGColor]]; [myLayer setBackgroundColor: [[UIColor whiteColor] CGColor]];
您还需要包含QuartzCore框架并在您自己的框架中包含框架标头.
#include <QuartzCore/QuartzCore.h>
希望这可以帮助
蒂姆
