来自自定义原型单元中的 UIButton 的 PrepareForSegue

Question

正如标题所说，我有一个带有原型单元格的 tableView；单元格是一个自定义单元格（所以我创建了一个名为CustomCell.swift 的类，我为图像、标签、按钮等创建了IBOutlet）；这是我的课

import UIKit

class CustomCell: UITableViewCell
{
    @IBOutlet var imageSquadra: UIImageView!
    @IBOutlet var button: UIButton!

    override func awakeFromNib()
    {
        super.awakeFromNib()
        // Initialization code
    }

    override func setSelected(selected: Bool, animated: Bool)
    {
        super.setSelected(selected, animated: animated)

        // Configure the view for the selected state
    }
}

然后我做了UITableViewController:

import UIKit

class SquadreController: UITableViewController
{
    var index: NSIndexPath?
    var isScrolling = Bool()

    override func viewDidLoad()
    {
        super.viewDidLoad()

        DataManager.sharedInstance.createCori()

    }

    override func didReceiveMemoryWarning()
    {
        super.didReceiveMemoryWarning()
    }

    override func numberOfSectionsInTableView(tableView: UITableView) -> Int
    {
        return 1
    }

    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int
    {
        return DataManager.sharedInstance.arrayCori.count
    }

    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
    {
        let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! CustomCell
        let squadra = DataManager.sharedInstance.arrayCori[indexPath.row]

        cell.backgroundColor = UIColor.clearColor()

        if (indexPath.row % 2 == 0)
        {
            cell.backgroundColor = UIColor.greenColor()
        }
        else
        {
            cell.backgroundColor = UIColor.blueColor()
        }

        //Here I added target to the button in the cell, and below in the class I implemented the fun makeSegue()
        cell.button.addTarget(self, action: "makeSegue", forControlEvents: UIControlEvents.TouchUpInside)

        return cell
    }


    //Following 4 method are used to detect UIScollView scrolling and to change cell height.
    override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath)
    {
        tableView.deselectRowAtIndexPath(indexPath, animated: true)
        index = indexPath
        tableView.beginUpdates()
        tableView.endUpdates()
    }

    override func scrollViewWillBeginDragging(scrollView: UIScrollView)
    {
        isScrolling = true
        tableView.beginUpdates()
        tableView.endUpdates()
    }

    override func scrollViewDidEndDragging(scrollView: UIScrollView, willDecelerate decelerate: Bool)
    {
        isScrolling = false
    }

    override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat
    {
        if isScrolling
        {
            return 100
        }

        if index == indexPath
        {
            return 200
        }
        else
        {
            return 100
        }
    }

    //Here I implemented the makeSegue() func, the action I had made as target of the button.
    func makeSegue() {
        self.performSegueWithIdentifier("toCoriViewController", sender: self)
    }
}

好的，现在最困难的部分来了：制作prepareForSegue;我没有任何想法如何解决这个问题，我试过了

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?)
    {
        if segue.identifier == "toCoriViewController"
        {
            if let indexPath = ?????????????
            {
                let controller = segue.destinationViewController as! CoriViewController
                controller.coriSquadra = DataManager.sharedInstance.arrayCori[indexPath.row]
            }
        }
    }

但我不知道如何设置常量indexPath。

哦，首先我通过控制权从按钮到第二个控制器进行了转场：也许我必须从 tableView 单元格进行转场？？？

希望有人可以帮助我！

Answer 1

你可以像这样得到单元格的索引路径

let indexPath : NSIndexPath
if let button = sender as? UIButton {
    let cell = button.superview?.superview as! UITableViewCell
    indexPath = self.tableView.indexPathForCell(cell)
}

您还需要像这样更改您的makeSegue：

func makeSegue(button:UIButton) {
    self.performSegueWithIdentifier("toCoriViewController", sender: button)
}

在您的cellForRowAtIndexPath 中，只需将您设置操作的行更改为cell.button.addTarget(self, action: "makeSegue:", forControlEvents: UIControlEvents.TouchUpInside)。

或者，您可以在自定义单元格类中创建一个squadra 属性来保存该单元格的arrayCori 值，因此您将拥有一些如下所示的代码：

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
{
    let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! CustomCell
    let squadra = DataManager.sharedInstance.arrayCori[indexPath.row]
    cell.squadra = squadra #add this line
    cell.backgroundColor = UIColor.clearColor()
    if (indexPath.row % 2 == 0)
    {
        cell.backgroundColor = UIColor.greenColor()
    }
    else
    {
        cell.backgroundColor = UIColor.blueColor()
    }

    //Here I added target to the button in the cell, and below in the class I implemented the fun makeSegue()
    cell.button.addTarget(self, action: "makeSegue", forControlEvents: UIControlEvents.TouchUpInside)

    return cell
}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?)
{
    if segue.identifier == "toCoriViewController"
    {
        let controller = segue.destinationViewController as! CoriViewController
        if let button = sender as? UIButton {
            let cell = button.superview?.superview as! CustomCell
            controller.coriSquadra = cell.squadra
        }
    }
}

Answer 2

故事板 + prepareForSegue

只需添加一个单独的UIStoryboardSegue 并为故事板中的按钮添加一个单独的标识符，几乎无需代码即可完成。

prepareForSegue 变为：

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if "fromButtonToViewController" == segue.identifier {
        if let button = sender as? UIButton {
            // ... The UIButton is the sender
        }
    }
}

这会同时或单独处理点击单元格和点击按钮，将正确的sender 传递给prepare:segue:sender，从而允许自定义单元格、按钮、转换以及最终的目标视图。该语句的演示可以在下面的紧凑项目中找到。

---

► 在GitHub 上查找此解决方案，在Swift Recipes 上查找更多详细信息。

Answer 3

对于那些正在寻找通用方法的人。

/* Generic function to get uitableviewcell from any UIKit controllers which stored in deep level of views or stackviews */

func getCell<T>(_ view: T) -> UITableViewCell? {

    guard let view = view as? UIView else {
        return nil
    }

    return view as? UITableViewCell ?? getCell(view.superview)
}


override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?)
{
    if segue.identifier == "toCoriViewController"
    {
        if let button = sender as? UIButton,
            let cell = getCell(button),
            let indexPath = tableView.indexPath(for: cell)
        {
            let controller = segue.destinationViewController as! CoriViewController
            controller.coriSquadra = DataManager.sharedInstance.arrayCori[indexPath.row]
        }
    }
}