ios - 在自定义方法中访问 UICollectionViewCell 组件

Question

我在 UICollectionViewCell 中有一些组件，我可以访问 cellForItemAtIndexPath 中的所有组件。我需要在自定义方法中访问组件，

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
    // UIButton
    cell.btn1.frame =CGRectMake(380,100, 150, 40);
    [cell.btn1 addTarget:self action:@selector(btnClicked) forControlEvents:UIControlEventTouchUpInside];
  return cell;
}

在自定义方法中，

-(void)btnClicked{
MycollectionclassView *cell =[[MycollectionclassView alloc]init];
cell.btn1.backgroundColor =[UIColor greenColor];
}

这里我不能改变按钮的颜色。

Answer 1

您必须创建协议(protocol)并为方法创建 IBAction。当您的操作方法被调用时，您可以通知协议(protocol)，其具有 UICollectionView 协议(protocol)的屏幕将接收此事件。

在单元头文件.h 中定义协议(protocol):

@protocol YourCellNamelDelegate <NSObject>

@required
/**
 *  Notifies that current ITEM was clicked on icon.
 *
 *  @param cell The current cell that was clicked.
 */
-(void)bookmarkClicked:(YourCellName *)cell; // OR without argument


@interface YourCellName : UITableViewCell

/**
 *  Reference to 'YourCellNameDelegate' delegate.
 */
@property (assign,nonatomic) id<YourCellNamelDelegate>delegate;

...

在您的手机文件中。m

...

- (IBAction)bookmarkClickAction:(id)sender {

   // change or update screen element here ...

    if (self.delegate) {
        [self.delegate bookmarkClicked:self];
    }

}

在您的 ViewController 上实现您的协议(protocol)

@interface SMGListViewController () <YourCellNameDelegate>


-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {

// get your cell here, for example in my case:    

    SMGCityGuideCollectionViewCell *cell;
    cell = (SMGCityGuideCollectionViewCell *)[collectionView dequeueReusableCellWithReuseIdentifier:reuseIdentifier forIndexPath:indexPath];

    SMGTouristInfo *touristInfo =  [self.listTouristInfo objectAtIndex:indexPath.row];
    [cell setTouristInfoCell:touristInfo];

    // IMPORTANT HERE *************************
    cell.delegate = self;  
    // IMPORTANT HERE *************************

    return cell;
}
...


#pragma mark <SMGPlaceCellDelegate>

-(void)bookmarkClicked:(SMGPlaceCell *)cell {

    // notify events here ...

    NSIndexPath *index = [self.tableViewPlaces indexPathForCell:cell];
    [self.tableViewPlaces reloadRowsAtIndexPaths:@[index] withRowAnimation:UITableViewRowAnimationAutomatic];
}

希望对您有帮助! :)