ios - CollectionView多单元格选择

Question

我有一个包含两个自定义单元格的 Collection View ，一个用于网格，一个用于列表，我希望能够触摸单元格并选择它们，就好像要删除或共享它们一样，我现在想要的只是能够选择和取消选择它们，我会在下面发布我的代码，结果是当我触摸一个单元格时，所有单元格都被选中!这是代码:

func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
    if isGridSelected {

        let cell:cell2_Class = collectionView.dequeueReusableCellWithReuseIdentifier("cell2", forIndexPath: indexPath) as! cell2_Class

        cell.listImage.image = imageArray[indexPath.row]

        if flag == true {
            cell.layer.borderColor = UIColor.blueColor().CGColor
            cell.layer.borderWidth = 3
            cancelButton.hidden = false
        } else {
            cell.layer.borderColor = UIColor.clearColor().CGColor
            cancelButton.hidden = true
        }
        return cell
    } else {
        let cell:PhotoCollectionCell = collectionView.dequeueReusableCellWithReuseIdentifier("cell", forIndexPath: indexPath) as! PhotoCollectionCell

        if flag == true {
            cell.layer.borderColor = UIColor.blueColor().CGColor
            cell.layer.borderWidth = 3
            cancelButton.hidden = false
        } else {
            cell.layer.borderColor = UIColor.clearColor().CGColor
            cancelButton.hidden = true
        }
        cell.imageView.image = imageArray[indexPath.row]
        cell.NameLabel.text = namelabel[indexPath.row]
        cell.ModifiedLbl.text = modfLabel[indexPath.row]

        return cell
    }
}

func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {

    let cell = collectionView.cellForItemAtIndexPath(indexPath)

    if cell!.selected == true {
        flag = true
    } else {
        flag = false 
    }
    self.collectionView.reloadData()
}

Answer 1

在 PhotoCollectionCell 和 cell2_Class 中(或在普通的 superclass 中)简单地覆盖这个方法

- (void) setSelected:(BOOL)selected 
{ 
     if (selected) 
     {        
         self.layer.borderColor = UIColor.blueColor().CGColor
         self.layer.borderWidth = 3
     } 
     else 
     {
         self.layer.borderColor = UIColor.clearColor().CGColor
     }
}

那么您就不必在delegate 或dataSource 中处理实际的选择/突出显示。

确保您的 collectionView 的属性 allowsSelection 为 YES。

如果您想要多选，那么还要将allowsMultipleSelection 设置为YES 并在您的委托(delegate) 中实现以下方法

- (BOOL) collectionView:(UICollectionView *)collectionView shouldSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
    if ([collectionView.indexPathsForSelectedItems containsObject: indexPath])
    {
        [collectionView deselectItemAtIndexPath: indexPath animated: YES];
        return NO;            
    }
    return YES;
}

快速解决方案

collectionViewCell 的子类

override var selected: Bool {
    didSet {
        self.layer.borderWidth = 3.0
        self.layer.borderColor = selected ? UIColor.blueColor().CGColor : UIColor.clearColor().CGColor
    }
}

在 UICollectionViewDelegate 中:

func collectionView(collectionView: UICollectionView, shouldSelectItemAt indexPath: NSIndexPath) -> Bool {
    if let selectedItems = collectionView.indexPathsForSelectedItems() {
        if selectedItems.contains(indexPath) {
            collectionView.deselectItemAtIndexPath(indexPath, animated: true)
            return false
        }
    }
    return true
}