Question

我有一个viewController，其TableView和accessoryType detailbutton的{{1}}。按下accessoryType时，我会显示带文字的半透明视图。

我希望此视图以特定方式显示，因此我创建了一个自定义视图控制器。

然而，尝试在detailbutton中运行该viewController将无效。

我的部分代码：

//Defined in the class
let customTransitionManager = TransitionManager()

//in tableView cellForRowAtIndexPath
if (tableView == continent){
        let cell:UITableViewCell = UITableViewCell(style:UITableViewCellStyle.Default, reuseIdentifier: "continentSelector")
        cell.textLabel?.text = "Continent"
        cell.accessoryType = UITableViewCellAccessoryType.DetailButton;
        return cell


func tableView(tableView: UITableView, accessoryButtonTappedForRowWithIndexPath indexPath: NSIndexPath){
    println(indexPath)
    let detailController = storyboard?.instantiateViewControllerWithIdentifier("detailButtonStoryBoard") as? detailedView
    detailController?.modalPresentationStyle = .Custom
    detailController?.transitioningDelegate = customTransitionManager;
    presentViewController(detailController!, animated: true, completion: nil)
}

运行此代码会出现以下错误：

fatal error: unexpectedly found nil while unwrapping an Optional value

以下内容突出显示：

-> 0x100209cf0 <function signature specialization <Arg[0] = Exploded, Arg[1] = Exploded, Arg[2] = Dead, Arg[3] = Dead> of Swift._fatalErrorMessage (Swift.StaticString, Swift.StaticString, Swift.StaticString, Swift.UInt) -> ()+44>: brk    #0x1

Answer 1

我看到两个你可以有零值的地方。第一个是在索引路径的行的单元格中，但这不太可能。第二个也是更有可能的是你在展示detailContoller时尝试打开它的地方。您是否确认从故事板中取回控制器？

更新：我在评论中放置的解决方案格式可怕，这是一个更好的格式

找到解决方案使用segue而不是手动显示控制器。

从didSelectRowAtIndexPath

把这个：

let toViewController = segue.destinationViewController as UIViewController
toViewController.transitioningDelegate = self.customTransitionManager`

完全归功于本教程：http://mathewsanders.com/animated-transitions-in-swift/#custom-transition-animations

更新2：下载了您的项目并使其正常运行。以下是我所做的更改：

我在牛仔裤控制器和细节控制器之间添加了一个模态segue。我称之为'DetailSegue'

我更新了jeans.swift文件accessoryButtonTappedForRowWithIndexPath方法，如下所示：

func tableView(tableView: UITableView, accessoryButtonTappedForRowWithIndexPath indexPath: NSIndexPath){
    println(indexPath)
    self.performSegueWithIdentifier("DetailSegue", sender: self)
}

然后我更新了TransitionManger animateTransition函数，如下所示，基本上使to和from视图可选，并适当处理nil

func animateTransition(transitionContext: UIViewControllerContextTransitioning) {
    //get reference to our FROM View, To View, and container view that we should perform the transition in
    let container = transitionContext.containerView()

    let fromView = transitionContext.viewForKey(UITransitionContextFromViewKey)
    let toView = transitionContext.viewForKey(UITransitionContextToViewKey)

    //setup from 2D transform that we'll use in the animation
    let offScreenRight = CGAffineTransformMakeTranslation(container.frame.width, 0)
    let offScreenLeft = CGAffineTransformMakeTranslation(-container.frame.width, 0)

    //start the view to the right of the screen 
    toView?.transform = offScreenRight

    //add both the views to our view controller
    if toView != nil {
        container.addSubview(toView!)
    }

    if fromView != nil {
        container.addSubview(fromView!)
    }

    // get the duration of the animation
    let duration = self.transitionDuration(transitionContext)

    //perform the animation

    UIView.animateWithDuration(duration, delay: 0.0, options: nil, animations: {
        fromView?.transform = offScreenLeft
        toView?.transform = CGAffineTransformIdentity
        }, completion: { finished in transitionContext.completeTransition(true)})
}

以下是最终结果的截屏视频：http://screencast.com/t/2mC07BLCC

我希望这可以帮助您推进项目。

在swift中向presentViewController添加自定义转换

1 个答案: