Swift 4 - 如果已选择，请取消选择集合视图单元格

Posted 2023-02-23

【中文标题】Swift 4 - 如果已选择，请取消选择集合视图单元格

【英文标题】：Swift 4 - deselect collection view cell if already selected

【发布时间】：2018-02-05 17:54:16

【问题描述】：

我有一个集合视图，用户可以在其中选择多个单元格并将索引数组发送到服务器以保存他们的选择。

一切正常，除了在创建集合视图时需要单击所选项目两次才能取消选择它们。

如何解决双击的问题？

extension ThirdViewController: UICollectionViewDelegate, UICollectionViewDataSource 


    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int 

        return categoryList.count
    

    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell 
         let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellIdentifier, for: indexPath) as! UserCategoryCollectionViewCell

        cell.categoryLbl.text = categoryList[indexPath.row]

        if Defaults.hasKey(.categoryListIndices) 
            if (Defaults[.categoryListIndices]?.contains(indexPath.row))! 
                cell.alpha = 0.1
                cell.isSelected = true
             else 

                cell.alpha = 1

            
        

        return cell
    


    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) 
        let cell = collectionView.cellForItem(at: indexPath) as! UserCategoryCollectionViewCell


        cell.alpha = 0.1

    

    func collectionView(_ collectionView: UICollectionView, didDeselectItemAt indexPath: IndexPath) 
        let deselectedCell = collectionView.cellForItem(at: indexPath) as? UserCategoryCollectionViewCell
        deselectedCell?.alpha = 1

        print(deselectedCell?.isSelected)
        collectionView.deselectItem(at: indexPath, animated: false)
    

【问题讨论】：

您必须将UITapGestureRecognizer 和setNumberOfTapsRequired = 2 设置为单元格以进行双击事件。

【参考方案1】：

首先。将此添加到您的 viewDidLoad。

 collectionView?.allowsMultipleSelection = true

然后添加这两个函数。

 override func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) 
    let cell=collectionView.cellForItem(at: indexPath)
    collectionView.selectItem(at: indexPath, animated: true, scrollPosition: [])
    cell?.backgroundColor = Color.hexStringToUIColor(hex: "#F5A331")
    let lbl = cell?.subviews[1] as! UILabel
    lbl.textColor = Style.cellHighlightedColor

 override func collectionView(_ collectionView: UICollectionView, didDeselectItemAt indexPath: IndexPath) 
    collectionView.deselectItem(at: indexPath, animated: true)
    let cell=collectionView.cellForItem(at: indexPath)
    collectionView.deselectItem(at: indexPath, animated: true)
    
    cell?.backgroundColor = UIColor.white
    let lbl = cell?.subviews[1] as! UILabel
    lbl.textColor = UIColor.darkGray

这样就可以了