快速调用LoadView函数两次

Question

I have a problem: I add all buttons and other outlets manually in the loadView() function. Due to the big amount of buttons I add them in the loadView() function to an array. But apparently the loadView() function is called twice so that I don't have 10 objects in my array but 20. Can anyone explain to me why the function is called twice and what I have to do now?

My Code:

private let myCreator = CreatorClass()
private var loadGameSlots = [UIButton]()

override func loadView() {
    UIApplication.sharedApplication().statusBarHidden = true

    for var i=0;i<5;i++ {
        var stringD:String
        var stringE:String
        if (data.delegate.allFileNames.count == 0) || (data.delegate.allFileNames.count == i+1) {
            stringD = "Nichts gespeichert"
            stringE = "Nothing saved"
        }
        else {
            stringD = data.delegate.allFileNames[i] as String
            stringE = data.delegate.allFileNames[i] as String
        }
        let myButton:UIButton = UIButton.buttonWithType(UIButtonType.Custom) as UIButton
        self.myCreator.createButton(myButton, frameForIPhone5: CGRect(x: 45, y: 195, width: 230, height: 25), titleD: stringD, titleE: stringE, bold: false, size: 18.0, titleColor: UIColor.whiteColor(), highlightedColor: UIColor.whiteColor(), shadowColor: nil, offset: 0, backgroundImage: "StartingPageButton.png", backgroundColor: UIColor.clearColor(), action: "loadGameSlotTouched:", target: self, viewToAdd: self.view)
        self.loadGameSlots += [myButton]
        myButton.hidden = true
    }
}

The .createButton method is kind of a custom class:

func createButton(button:UIButton!,var frameForIPhone5:CGRect?,titleD:String?,titleE:String?,bold:Bool?,var size:CGFloat,titleColor:UIColor?,highlightedColor:UIColor?,shadowColor:UIColor?,var offset:CGFloat?,backgroundImage:String?,backgroundColor:UIColor,action:Selector,target:AnyObject?,viewToAdd:UIView?) {

    func adjustSizes () {
        let constantY:CGFloat = viewRect.height / 568.0
        let constantX:CGFloat = viewRect.width / 320.0
        frameForIPhone5! = CGRect(x: frameForIPhone5!.origin.x * constantX, y: frameForIPhone5!.origin.y * constantY, width: frameForIPhone5!.width * constantX, height: frameForIPhone5!.height * constantY)
        size *= constantY
        offset! *= constantY
    }
    adjustSizes()
    button.frame = frameForIPhone5!
    if myData.delegate.selectedLanguage == "Deutsch" {
        button.setTitle(titleD!, forState: UIControlState.Normal)
    }
    else {
        button.setTitle(titleE!, forState: UIControlState.Normal)
    }
    if bold! {
        button.titleLabel!.font = UIFont(name: "Futura-CondensedExtraBold", size: size)
    }
    else {
        button.titleLabel!.font = UIFont(name: "Futura-Medium", size: size)
    }
    button.setTitleColor(titleColor?, forState: UIControlState.Normal)
    button.setTitleColor(highlightedColor?, forState: UIControlState.Highlighted)
    button.titleLabel!.shadowColor = shadowColor?
    button.titleLabel!.shadowOffset = CGSize(width: offset!, height: offset!)
    button.setBackgroundImage(UIImage(named: backgroundImage!), forState: UIControlState.Normal)
    button.backgroundColor = backgroundColor
    button.addTarget(target, action: action, forControlEvents: UIControlEvents.TouchUpInside)
    viewToAdd?.addSubview(button)
}

It's a lot of code now, but I don't know what you need to answer :)

PS: I didn't write anything in the viewDidLoad() function

Output:

(lldb) bt
* thread #1: tid = 0x66195, 0x0000000102bebbbd Airline Star Swift`Airline_Star_Swift.StartingPageViewController.loadView (self=0x00007fcffbe26120)() -> () + 10413 at StartingPageViewController.swift:51, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
  * frame #0: 0x0000000102bebbbd Airline Star Swift`Airline_Star_Swift.StartingPageViewController.loadView (self=0x00007fcffbe26120)() -> () + 10413 at StartingPageViewController.swift:51
    frame #1: 0x0000000102bec4f2 Airline Star Swift`@objc Airline_Star_Swift.StartingPageViewController.loadView (Airline_Star_Swift.StartingPageViewController)() -> () + 34 at StartingPageViewController.swift:0
    frame #2: 0x0000000103798ef9 UIKit`-[UIViewController loadViewIfRequired] + 75
    frame #3: 0x000000010379938e UIKit`-[UIViewController view] + 27
    frame #4: 0x00000001036c3964 UIKit`-[UIWindow handleStatusBarChangeFromHeight:toHeight:] + 948
    frame #5: 0x00000001036c6308 UIKit`+[UIWindow _noteStatusBarHeightChanged:oldHeight:forAutolayoutRootViewsOnly:] + 235
    frame #6: 0x0000000103676a2e UIKit`__79-[UIApplication _setStatusBarHidden:animationParameters:changeApplicationFlag:]_block_invoke + 141
    frame #7: 0x00000001036e5c42 UIKit`+[UIView(UIViewAnimationWithBlocks) _setupAnimationWithDuration:delay:view:options:factory:animations:start:animationStateGenerator:completion:] + 473
    frame #8: 0x00000001036e5ed8 UIKit`+[UIView(UIViewAnimationWithBlocks) animateWithDuration:animations:completion:] + 59
    frame #9: 0x0000000103676901 UIKit`-[UIApplication _setStatusBarHidden:animationParameters:changeApplicationFlag:] + 490
    frame #10: 0x0000000103676cf2 UIKit`-[UIApplication setStatusBarHidden:withAnimation:] + 126
    frame #11: 0x0000000102be93a8 Airline Star Swift`Airline_Star_Swift.StartingPageViewController.loadView (self=0x00007fcffbe26120)() -> () + 152 at StartingPageViewController.swift:18
    frame #12: 0x0000000102bec4f2 Airline Star Swift`@objc Airline_Star_Swift.StartingPageViewController.loadView (Airline_Star_Swift.StartingPageViewController)() -> () + 34 at StartingPageViewController.swift:0
    frame #13: 0x0000000103798ef9 UIKit`-[UIViewController loadViewIfRequired] + 75
    frame #14: 0x000000010379938e UIKit`-[UIViewController view] + 27
    frame #15: 0x00000001036b8db9 UIKit`-[UIWindow addRootViewControllerViewIfPossible] + 58
    frame #16: 0x00000001036b9152 UIKit`-[UIWindow _setHidden:forced:] + 276
    frame #17: 0x00000001036c565c UIKit`-[UIWindow makeKeyAndVisible] + 42
    frame #18: 0x0000000103670191 UIKit`-[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 2628
    frame #19: 0x0000000103672e5c UIKit`-[UIApplication _runWithMainScene:transitionContext:completion:] + 1350
    frame #20: 0x0000000103671d22 UIKit`-[UIApplication workspaceDidEndTransaction:] + 179
    frame #21: 0x00000001064c82a3 FrontBoardServices`__31-[FBSSerialQueue performAsync:]_block_invoke + 16
    frame #22: 0x0000000102d1fabc CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 12
    frame #23: 0x0000000102d15805 CoreFoundation`__CFRunLoopDoBlocks + 341
    frame #24: 0x0000000102d155c5 CoreFoundation`__CFRunLoopRun + 2389
    frame #25: 0x0000000102d14a06 CoreFoundation`CFRunLoopRunSpecific + 470
    frame #26: 0x0000000103671799 UIKit`-[UIApplication _run] + 413
    frame #27: 0x0000000103674550 UIKit`UIApplicationMain + 1282
    frame #28: 0x0000000102be6ede Airline Star Swift`top_level_code + 78 at AppDelegate.swift:13
    frame #29: 0x0000000102be6f1a Airline Star Swift`main + 42 at AppDelegate.swift:0
    frame #30: 0x0000000105107145 libdyld.dylib`start + 1
(lldb) 

And after the second breakpoint:

(lldb) bt
* thread #1: tid = 0x66195, 0x0000000102bebbbd Airline Star Swift`Airline_Star_Swift.StartingPageViewController.loadView (self=0x00007fcffbe26120)() -> () + 10413 at StartingPageViewController.swift:51, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
  * frame #0: 0x0000000102bebbbd Airline Star Swift`Airline_Star_Swift.StartingPageViewController.loadView (self=0x00007fcffbe26120)() -> () + 10413 at StartingPageViewController.swift:51
    frame #1: 0x0000000102bec4f2 Airline Star Swift`@objc Airline_Star_Swift.StartingPageViewController.loadView (Airline_Star_Swift.StartingPageViewController)() -> () + 34 at StartingPageViewController.swift:0
    frame #2: 0x0000000103798ef9 UIKit`-[UIViewController loadViewIfRequired] + 75
    frame #3: 0x000000010379938e UIKit`-[UIViewController view] + 27
    frame #4: 0x00000001036b8db9 UIKit`-[UIWindow addRootViewControllerViewIfPossible] + 58
    frame #5: 0x00000001036b9152 UIKit`-[UIWindow _setHidden:forced:] + 276
    frame #6: 0x00000001036c565c UIKit`-[UIWindow makeKeyAndVisible] + 42
    frame #7: 0x0000000103670191 UIKit`-[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 2628
    frame #8: 0x0000000103672e5c UIKit`-[UIApplication _runWithMainScene:transitionContext:completion:] + 1350
    frame #9: 0x0000000103671d22 UIKit`-[UIApplication workspaceDidEndTransaction:] + 179
    frame #10: 0x00000001064c82a3 FrontBoardServices`__31-[FBSSerialQueue performAsync:]_block_invoke + 16
    frame #11: 0x0000000102d1fabc CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 12
    frame #12: 0x0000000102d15805 CoreFoundation`__CFRunLoopDoBlocks + 341
    frame #13: 0x0000000102d155c5 CoreFoundation`__CFRunLoopRun + 2389
    frame #14: 0x0000000102d14a06 CoreFoundation`CFRunLoopRunSpecific + 470
    frame #15: 0x0000000103671799 UIKit`-[UIApplication _run] + 413
    frame #16: 0x0000000103674550 UIKit`UIApplicationMain + 1282
    frame #17: 0x0000000102be6ede Airline Star Swift`top_level_code + 78 at AppDelegate.swift:13
    frame #18: 0x0000000102be6f1a Airline Star Swift`main + 42 at AppDelegate.swift:0
    frame #19: 0x0000000105107145 libdyld.dylib`start + 1

I'm confused because I did the exactly same thing in Objective-C but it worked perfectly

Thanks in advance! :)

Answer 1

The problem is this line:

 self.myCreator.createButton(myButton, frameForIPhone5: CGRect(x: 45, y: 195, width: 230, height: 25), titleD: stringD, titleE: stringE, bold: false, size: 18.0, titleColor: UIColor.whiteColor(), highlightedColor: UIColor.whiteColor(), shadowColor: nil, offset: 0, backgroundImage: "StartingPageButton.png", backgroundColor: UIColor.clearColor(), action: "loadGameSlotTouched:", target: self, viewToAdd: self.view)

You are mentioning self.view inside loadView . But inside loadView there is no self.view ; its job, in fact, is to create one, but you are not creating it. That's circular and causes loadView to be called twice.

The ultimate source of the problem is that you should never have implemented loadView in the first place. Perhaps when you did this in Objective-C you used viewDidLoad , but now you have accidentally changed it to loadView and this is messing you up.

Answer 2

loadView is wrong place to create your entire view hierarchy. You should only create top view (which is self.view) in loadView. First create self.view in loadView then do other stuff in viewDidLoad.