如何在prepare(for: segue)中使用SwipeCellKit的indexPath传递数据

问题场景 #

点击UITableView单元格行时，以下代码能正常将Auto对象传递到目标视图控制器：

override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    print(indexPath.row)
    performSegue(withIdentifier: "editAutoDetailsSegue", sender: self)
}

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "editAutoDetailsSegue" {
        print("Preparing to segue")
        let destinationVC = segue.destination as! EditAutoInfoViewController
        if let indexPath = tableView.indexPathForSelectedRow {
            print("Row Selected")
            destinationVC.selectedAuto = autombiles?[indexPath.row]
        }
    }
}

但使用SwipeCellKit实现滑动显示编辑按钮后，点击编辑按钮执行segue时无法传递Auto对象。当前滑动操作的代码如下：

extension AutoViewController: SwipeTableViewCellDelegate {
    func tableView(_ tableView: UITableView, editActionsForRowAt indexPath: IndexPath, for orientation: SwipeActionsOrientation) -> [SwipeAction]? {
        guard orientation == .right else { return nil }

        let deleteAction = SwipeAction(style: .destructive, title: "Delete") { action, indexPath in
            if let theAuto = self.autombiles?[indexPath.row] {
                do {
                    try self.realm.write {
                        self.realm.delete(theAuto)
                    }
                } catch {
                    print("There was an error deleting the auto \(error)")
                }
            }
        }
        
        let editAction = SwipeAction(style: .default, title: "Edit") { action, indexPath in
            self.performSegue(withIdentifier: "editAutoDetailsSegue", sender: self)
        }

        return [deleteAction, editAction]
    }
    
    func tableView(_ tableView: UITableView, editActionsOptionsForRowAt indexPath: IndexPath, for orientation: SwipeActionsOrientation) -> SwipeOptions {
        var options = SwipeOptions()
        options.expansionStyle = .destructive
        options.transitionStyle = .border
        return options
    }
}

核心原因 #

滑动点击编辑按钮时，单元格并未被选中，tableView.indexPathForSelectedRow会返回nil，导致无法获取对应的Auto对象。

解决方案 #

方案1：传递indexPath作为sender

修改编辑按钮的闭包，将当前的indexPath作为performSegue的sender参数：

let editAction = SwipeAction(style: .default, title: "Edit") { action, indexPath in
    self.performSegue(withIdentifier: "editAutoDetailsSegue", sender: indexPath)
}

然后更新prepare(for:sender:)方法，同时处理两种sender类型：

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "editAutoDetailsSegue" {
        print("Preparing to segue")
        let destinationVC = segue.destination as! EditAutoInfoViewController
        
        // 处理点击单元格的情况
        if let indexPath = tableView.indexPathForSelectedRow {
            print("Row Selected")
            destinationVC.selectedAuto = autombiles?[indexPath.row]
        }
        // 处理滑动编辑按钮的情况
        else if let indexPath = sender as? IndexPath {
            print("Swipe Edit Action Triggered")
            destinationVC.selectedAuto = autombiles?[indexPath.row]
        }
    }
}

方案2：直接传递Auto对象（更简洁）

在编辑按钮闭包中直接获取对应的Auto对象并作为sender传递：

let editAction = SwipeAction(style: .default, title: "Edit") { action, indexPath in
    if let selectedAuto = self.autombiles?[indexPath.row] {
        self.performSegue(withIdentifier: "editAutoDetailsSegue", sender: selectedAuto)
    }
}

然后更新prepare(for:sender:)方法，处理Auto类型的sender：

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "editAutoDetailsSegue" {
        print("Preparing to segue")
        let destinationVC = segue.destination as! EditAutoInfoViewController
        
        // 处理点击单元格的情况
        if let indexPath = tableView.indexPathForSelectedRow {
            print("Row Selected")
            destinationVC.selectedAuto = autombiles?[indexPath.row]
        }
        // 处理滑动编辑按钮的情况
        else if let selectedAuto = sender as? Auto {
            print("Swipe Edit Action Triggered")
            destinationVC.selectedAuto = selectedAuto
        }
    }
}

说明 #

两种方案都能解决问题，方案2更直接，减少了通过indexPath查找数据的步骤；方案1则保留了indexPath的灵活性，适合需要额外使用indexPath的场景。

内容的提问来源于stack exchange，提问作者Jon