对于一个CollectionView而言，多个Cell，而每个cell都有一样的按钮。那么怎么在生成按钮时给每个按钮传递indexPath.row的参数给按钮，让每次响应UIControlEventTouchUpInside又能获到呢？此时可以考虑运行时，如下：
//获取参数,object实参指定为按钮，key是@selector(paramValue:)对象
- (NSNumber *)paramValue:(id)object
{
return objc_getAssociatedObject(object, _cmd);
}
//设置参数，object实参指定为按钮，key是@selector(paramValue:)对象
- (void)setparamValue:(NSNumber *)value object:(id)object
{
objc_setAssociatedObject(object, @selector(paramValue:), value, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
//构造按钮并传递index.row
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
UIButton* collectButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[collectButton addTarget:self action:@selector(clickCollect:) forControlEvents:UIControlEventTouchUpInside];
[self setparamValue:@(indexPath.row) object:collectButton];
}
//响应方法获取index.row区别不同的按钮
-(void)clickCollect:(UIButton*)button
{
NSNumber *number = [self paramValue:button]
}
以上同样可以运用在tableviewcell的控件中。
