未执行Segue iOS8

Question

I am using XCode 6, targeting iOS 8 and coding this in Swift.

My storyboard controllers look like this:

Tab Bar > Navigation > Table View > Detail View

The Show Detail segue is from a Table Cell to the Detail View .

The prepareForSegue method is not triggered when clicking a table cell. Segue from a button to detail works fine, though. performSegueWithIdentifier in didSelectRowAtIndexPath also works fine.

I have also created a brand new test project to test this issue - the controller code looks like this:

import UIKit

class TestTableController: UITableViewController
{
    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int
    {
        return 2;
    }

    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
    {
        let cellId = "testCell";
        var cell: UITableViewCell? = tableView.dequeueReusableCellWithIdentifier(cellId) as? UITableViewCell;

        if (cell == nil)
        {
            cell = UITableViewCell(style: UITableViewCellStyle.Default, reuseIdentifier: cellId);
        }

        cell!.textLabel!.text = "cell \(indexPath.item)";

        return cell!;
    }
}

Any idea why this does not work out of the box?

PS: when using Split View instead of a Tab Bar , the same segue works fine.

Answer 1

This happened with me when I was registering cell in ViewDidLoad method using tableView.register(AnyClass?, forCellReuseIdentifier: String) When i commented this line and added the cell class and cell identifier in storyboard, it started working. Again if I uncomment that code in viewdidload, it stops working.

Answer 2

I just tested it with a sample project. It works fine. There must be something wrong with your wiring up the cell.

Here is my code. Only indicating changes from plain vanilla tab bar project template.

// FirstViewController.swift
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return 2
}

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    var cell = tableView.dequeueReusableCellWithIdentifier("Cell") as UITableViewCell
    cell.textLabel?.text = "Cell \(indexPath.row + 1)"
    return cell
}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    let detail = segue.destinationViewController as DetailController
    let cell = sender as UITableViewCell
    let indexPath = self.tableView.indexPathForCell(cell)
    detail.detailItem = "Cell \(indexPath!.row + 1)"
}

//DetailController.swift
class DetailController: UIViewController {

    var detailItem : String!
    @IBOutlet var label : UILabel!

    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated)
        label.text = detailItem
    }
}

Answer 3

for calling the method prepareForSegue you must have to add a segue to connect the prototype cell and the destination Controller! method doesn't called if you navigate to destination controller programmatically!