Swift 4使用动画在索引：0处添加和删除自定义单元格

Question

当在位置0的indexPath中添加新单元格时，我无法移动单元格。 当我要移动图片时，我想在索引0处添加带有动画的自定义单元格，我想移动我的图片，它应该从索引1开始，当我单击保存时，自定义单元格应该消失，图片会从索引0开始显示，并带有动画。

NewAlbumEmptyCollectionViewCell-自定义单元格

EditPhotoCollectionViewCell-默认图片单元格

@objc func saveAction(){
        if rightBarButton.title == "Edit"{
            rightBarButton.title = "Save"
            isEditEnabled = true
            UI.collectionView.reloadData()
        }else{
            rightBarButton.title = "Edit"
            isEditEnabled = false
            UI.collectionView.reloadData()
        }
    }

extension NewAlbumViewController: UICollectionViewDataSource, UICollectionViewDelegate{
    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        if isEditEnabled == true{
            print(photoAssets.count + 1)
            return photoAssets.count
        }else{
            print(photoAssets.count)
            return photoAssets.count
        }
    }

    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {

        if isEditEnabled == true{
            if indexPath.section == 0 && indexPath.row == 0 {
                let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "emptyCell", for: indexPath) as! NewAlbumEmptyCollectionViewCell
                return cell
            }else{
                let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "EditPhotoCollectionViewCell", for: indexPath) as! EditPhotoCollectionViewCell

                cell.data = photoAssets[indexPath.row]
                return cell
            }
        }else{
            let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "EditPhotoCollectionViewCell", for: indexPath) as! EditPhotoCollectionViewCell
            cell.data = photoAssets[indexPath.row]
            return cell
        }
    }
}

Answer 1

您错过了返回photoAssets.count + 1的增量值的操作。进行如下更改。

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    if isEditEnabled == true{

        print(photoAssets.count + 1)
        return photoAssets.count + 1
    }else{
        print(photoAssets.count)
        return photoAssets.count
    }
}

为获得流畅的动画效果：

@objc func saveAction(){
    if rightBarButton.title == "Edit"{
        rightBarButton.title = "Save"
        isEditEnabled = true
        UI.collectionView.insertItems(at: [IndexPath(item: 0, section: 0)])
    }else{
        rightBarButton.title = "Edit"
        isEditEnabled = false
        UI.collectionView.deleteItems(at: [IndexPath(item: 0, section: 0)])
    }
}