button点击切换背景图片的问题

我做了个UIButton的扩展，代码如下：

#import <UIKit/UIKit.h>

@interface CheckBoxButton : UIButton
@property (nonatomic,assign) BOOL isChecked;
@end

    if (button.isChecked) {
        self.collectionButton.imageView.image = [UIImage imageNamed:@"shouchang_do"];

    }else
    {
        self.collectionButton.imageView.image = [UIImage imageNamed:@"shouchang_undo"];

    }

    if (button.isChecked) {
        //self.collectionButton.imageView.image = [UIImage imageNamed:@"shouchang_do"];
        [self.collectionButton setImage:[UIImage imageNamed:@"shouchang_do"] forState:UIControlStateNormal];
    }else
    {
        //self.collectionButton.imageView.image = [UIImage imageNamed:@"shouchang_undo"];
        [self.collectionButton setImage:[UIImage imageNamed:@"shouchang_undo"] forState:UIControlStateNormal];

    }

button点击切换背景图片的问题

原文：http://blog.csdn.net/feixiang_song/article/details/41867809