IOS：通过长按选择 UICollectionView 单元格

Posted 2023-03-13

【中文标题】IOS：通过长按选择 UICollectionView 单元格

【英文标题】：IOS: Selecting UICollectionView Cell by Long Press

【发布时间】：2013-08-14 06:11:23

【问题描述】：

我正在使用UICollectionView 生成图片库。我在UICollectionView 单元格中使用UIImage 来加载图像。我需要通过长按（而不是单击）选择UICollectionView 单元格。

- (IBAction)longPress:(UILongPressGestureRecognizer *)gestureRecognizer


    UICollectionViewCell *cell=(UICollectionViewCell *)[gestureRecognizer view];
    int index=cell.tag;

    OverlayImage = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, cell.frame.size.width,     cell.frame.size.height)];
    OverlayImage.image = [UIImage imageNamed:@"[e-mail]"];
    [cell addSubview:OverlayImage];

【问题讨论】：

你可以使用UILongPressGestureRecognizer

【参考方案1】：

斯威夫特 4

it的更新答案

    let longPressGR = UILongPressGestureRecognizer(target: self, action: #selector(handleLongPress(longPressGR:)))
    longPressGR.minimumPressDuration = 0.5
    longPressGR.delaysTouchesBegan = true
    self.collectionView.addGestureRecognizer(longPressGR)


@objc
func handleLongPress(longPressGR: UILongPressGestureRecognizer) 
    if longPressGR.state != .ended 
        return
    
    
    let point = longPressGR.location(in: self.collectionView)
    let indexPath = self.collectionView.indexPathForItem(at: point)
    
    if let indexPath = indexPath 
        var cell = self.collectionView.cellForItem(at: indexPath)
        print(indexPath.row)
     else 
        print("Could not find index path")
    

【讨论】：

什么意思：“如果让 indexPath = indexPath ”

它解开indexPath，即self.collectionView.indexPathForItem(at: point)

【参考方案2】：

您可以使用LongPressGesture

UILongPressGestureRecognizer *longpressGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPressHandler:)];
    longpressGesture.minimumPressDuration = 5;
    [longpressGesture setDelegate:self];
    [self.yourImage addGestureRecognizer:longpressGesture];


    - (void)longPressHandler:(UILongPressGestureRecognizer *)gestureRecognizer 
        NSLog(@"longPressHandler");
        UIImageView *tempImage=(UIImageView*)[gestureRecognizer view];