在Swift

Question

我想将参数传递给 timer 中名为 selector 的函数。特别是对cell的引用，以便我可以更新 UI 中的内容。

所以我想要这样的东西：

timer = Timer.init(timeInterval: 1.0, target: self, selector: #selector(downloadTimer(cell: cell), userInfo: nil, repeats: true)

功能

func downloadTimer(cell: InnerCollectionCell) {
    cell.progressBar.setProgress(downloadProgress, animated: true)
}

虽然我可能有点侄女假设可以做到这一点？

------编辑------

根据以下示例，但未从单元格中获得预期结果

let innerCell: InnerCollectionCell = collectionView.dequeueReusableCell(withReuseIdentifier: reuseIdentifierInner, for: indexPath) as! InnerCollectionCell

timer = Timer.init(timeInterval: 1.0, target: self, selector: #selector(downloadTimer(_:)), userInfo: innerCell, repeats: true)


func downloadTimer(_ timer: Timer) {

    let cell = timer.userInfo

    cell. // no options as expected of a cell

}

如果数据发送正确，我期待更多这样的选项：

Answer 1

使用userinfo

设置您的计时器

timer = Timer.init(timeInterval: 1.0, target: self, selector: #selector(downloadTimer(cell: cell), userInfo: data, repeats: true)

并获取userinfo如下

func downloadTimer(_ timer: Timer) {
   let data = timer.userInfo
}

------编辑------

根据以下示例，但未从单元格中获得预期结果

let innerCell: InnerCollectionCell = collectionView.dequeueReusableCell(withReuseIdentifier: reuseIdentifierInner, for: indexPath) as! InnerCollectionCell

timer = Timer.init(timeInterval: 1.0, target: self, selector: #selector(downloadTimer(_:)), userInfo: innerCell, repeats: true)


func downloadTimer(_ timer: Timer) {

    let cell = timer.userInfo as! InnerCollectionCell

    cell. // no options as expected of a cell

}

Answer 2

在创建Timer时传入所需的数据作为userInfo参数：

timer = Timer.init(timeInterval: 1.0, target: self, selector: #selector(downloadTimer(_:), userInfo: myData, repeats: true)

并使回调看起来像：

func downloadTimer(_ timer: Timer) {
    // access timer.userInfo here
}