如何在 UICollectionView 中拥有自定义单元格

How to have custom cell in UICollectionView

我有一个 UICollectionView,我想让它显示 3 个自定义单元格。

我已阅读文档,但无法解决此问题。

有没有我遗漏的东西?

      func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    return 1
}

我尝试将 return 1 更改为 3 以显示 3 个自定义单元格,但它只会使第一个自定义单元格出现 3 次。

我已经创建了一个视频并链接到下面的视频来解释我的情况。

https://www.loom.com/share/9b5802d6cc7b4f9a93c55b4cf7d435bb

Edit I have used @Asad Farooq method and it seems to have worked for me. I added my CollectionView's shown below and I can now make custom cells!

    if(indexPath.item==0)
    {
        let cell  = collectionView.dequeueReusableCell(withReuseIdentifier: "DailyCollectionViewCell", for: indexPath) as! DailyCollectionViewCell
        return cell
    }
    if(indexPath.item==1)
    {
        let cell  = collectionView.dequeueReusableCell(withReuseIdentifier: "WeeklyCollectionViewCell", for: indexPath) as! WeeklyCollectionViewCell
        return cell
        
    }
    else {
    
        let cell  = collectionView.dequeueReusableCell(withReuseIdentifier: "MonthlyCollectionViewCell", for: indexPath) as! MonthlyCollectionViewCell
        return cell
    }
}

从Apple的documentation可以看出,

You typically don’t create instances of this class yourself. Instead, you register your specific cell subclass (or a nib file containing a configured instance of your class) using a cell registration. When you want a new instance of your cell class, call the dequeueConfiguredReusableCell(using:for:item:) method of the collection view object to retrieve one.

我们必须在使用之前将cell注册到collectionView,例如:

class CustomCollectionViewCell: UICollectionViewCell {
    // my custom collection view cell
}

然后我们将其注册到集合视图:

class MyViewController: UIViewController {
    ...
    override func viewDidLoad(){
        super.viewDidLoad()
        ...
        self.myCollectionView.dataSource = self
        // register the cells, so the collectionView will "know" which cell you are referring to.
        self.myCollectionView.register(UINib(nibName: "CustomCollectionViewCell", bundle: nil), forCellReuseIdentifier: "customReuseIdentifier")
        // register all type of cell you wanted to show.
    }

}

extension MyViewController: UICollectionViewDataSource {
    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        // return number of cell you wanted to show, based on your data model
        return 3
    }

    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = routineCollectionView.dequeueReusableCell(withReuseIdentifier: "customReuseIdentifier", for: indexPath) as! CustomCollectionViewCell
        // cast the cell as CustomCollectionViewCell to access any property you set inside the custom cell.
        // dequeue cell by the reuseIdentifier, "explain" to the collectionView which cell you are talking about.
        return cell
    }
}

上面的代码片段只是一个简短的例子,但我希望能解释这个想法。

如果您有多种类型的自定义单元格,则必须为它们创建 classes(UICollectionViewCell 的sub-class),将它们注册到您的 collectionView,并在 collectionView( cellForRowAt:).

网上有很多教程,这里分享我最喜欢的一个: https://www.raywenderlich.com/9334-uicollectionview-tutorial-getting-started

编辑:

如果您仅使用情节提要来添加自定义 collectionViewCell,则无需再次注册单元格,该单元格已存在于 collectionView 中(抱歉,以上代码只是我的偏好)。只需设置单元格的 class 和标识符,并使用 collectionView(cellForRowAt:).

中的标识符使单元格出列

我们必须在使用之前将三个不同的自定义单元格注册到 collectionView,然后在此函数中添加此代码

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

    if(indexPath.item==0)
    {
       let cell  = collectionView.dequeueReusableCell(withReuseIdentifier: "cell1", for: indexPath) as! cell1
return cell1
    }
if(indexPath.item==1)
    {
       let cell  = collectionView.dequeueReusableCell(withReuseIdentifier: "cell2", for: indexPath) as! cell2
return cell2
    
}
else
{
let cell  = collectionView.dequeueReusableCell(withReuseIdentifier: "cell3", for: indexPath) as! cell3
return cell3
    }