My viewController doesn't show up right - ios

in my iPad-app I am trying to present one of my views with a modal formsheet-style.
Here's some code:
-(void)present
{
SecondViewController *modal = [[SecondViewController alloc]init];
modal.modalPresentationStyle = UIModalPresentationStyleFormSheet;
[self presentModalViewController:modal animated:YES];
}
I am using Storyboard, and I have put stuff like a textView and toolbars in the view I'd like to show. I have set the right class in Identity Inspector, and in the class-files I have checked that it's the right view appearing with putting NSLog(#"Right view");
When calling the void present, a view is appearing, but only as a dark-white square. Nothing og my content from Storyboard is in it, I even tried changing the background color of the view and the textView to see if something was just outside the square, but the whole thing stayed white. It feels like it's not using the view I created in storyboard, but I have set it to the correct class, and the NSLog gets printed out when calling it. I have not connected the two views in any way in Storyboard, the SecondViewController is just floating around, so that might be the problem? The button that calls for -(void)present is created programmatically, so I can't ctrl+drag it to the button either.
Why is it showing an empty version of my class?

In the "Identity Inspector" set a "Storyboard ID" for your ViewController, and then present it like this:
-(void)present
{
SecondViewController *modal = [self.storyboard instantiateViewControllerWithIdentifier:#"myStoryboardID"];
modal.modalPresentationStyle = UIModalPresentationStyleFormSheet;
[self presentModalViewController:modal animated:YES];
}
And if you're using iOS6, presentModalViewController:animated: is deprecated, so use this:
-(void)present
{
SecondViewController *modal = [self.storyboard instantiateViewControllerWithIdentifier:#"myStoryboardID"];
modal.modalPresentationStyle = UIModalPresentationStyleFormSheet;
[self presentViewController:modal animated:YES completion:nil];
}

Your problem is that you're assuming the program will intrinsically know where to find the, already laid out, view for this controller when that's simply not how storyboards work. The code you list about will create a view controller, but without an associated view it will simply show as a black square.
There's a few ways to solve your dilemma:
Add the modal transition as a segue in the view controller, this would be the simplest way and is what iOS storyboards expect you to do.
Move the view from the storyboard to an external .xib and call the initWithNibName:bundle: method to load this as your view controller's view. This is the best solution if you just want to programmatically load the view.
Load the view from your storyboard programmatically with the instantiateViewControllerWithIdentifier: method, this is probably a bad idea as it goes against the design of storyboards.
I can elaborate on those if you want.

Related

iOS8 - Presenting a modal view removes sub view

I am updating our app to be compiled with xcode6/iOS8.
One issue I am running into is that when a modal view is presented. the underlying subview is removed. It is completely blacked out.. until the modal view is dismissed.. then it re-appears.
Has anyone run into this with iOS8? The same code has worked since iOS4.
Code:
PigDetailViewController *pigDetailViewController = [[PigDetailViewController alloc] initWithNibName:#"PigDetailViewController" bundle:nil];
self.navigationController.modalPresentationStyle = UIModalPresentationCurrentContext;
self.navigationController.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
[self presentViewController:pigDetailViewController animated:YES completion:nil];
In iOS 8 they've added a new presentation style that behaves like UIModalPresentationCurrentContext in the circumstance you've described, it's UIModalPresentationOverCurrentContext. The catch here is that unlike with UIModalPresentationCurrentContext, you want to set the view controller to be PRESENTED with this presentation style, like so:
PigDetailViewController *pigDetailViewController = [[PigDetailViewController alloc] initWithNibName:#"PigDetailViewController" bundle:nil];
pigDetailViewController.modalPresentationStyle = UIModalPresentationOverCurrentContext;
self.navigationController.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
[self presentViewController:pigDetailViewController animated:YES completion:nil];
Note that to support iOS 7 and below you'll likely need to check the OS version and decide how to present the view controller based on that.
edit: I'd like to add one more note to this. In iOS7 with UIModalPresentationCurrentContext, when the presented VC was dismissed, the underlying VC had its viewDidAppear method called. In iOS8 with UIModalPresentationOverCurrentContext, I've found the underlying VC does not have its viewDidAppear method called when the VC presented over top of it is dismissed.
Adding a point to BrennanR's answer.. even viewWillAppear doesn't call when the VC presented over top of it is dismissed.
I think you are misunderstanding how a modal view controller works.
When you present a view controller modally it will control the entire screen. It has an opaque background (normally black) and then draws its view on top of that.
So, if you set the view.backgroundColor to yellow (for example) it will have a yellow background. If you set it to clear then it will show through to the black background.
What I think you want is for the other view to "show through" so it looks like the modal view is sitting on top of it.
The best way I have found of doing this is to use this method...
// in the view controller that is presenting the modal VC
modalVC = // the modal VC that you will be presenting
UIView *snapshotView = [self.view snapshotViewAfterScreenUpdates:NO];
[modalVC.view insertSubView:snapshotView atIndex:0];
// present the modal VC
This will take a "screenshot" of the current view hierarchy and then place that snapshot underneath everything in the modal VC.
That way your black screen will be replaced by a screenshot of the previous view controller.

UISplitViewController detailview changing result is gray area

I am trying to replace the detailview of a UISplitViewController for a quite a while now, but the solutions I found on the internet wasn't useful.
I am executing this:
DetailViewController* secondVc = [[DetailViewController alloc] init];
NSMutableArray* arr = [[NSMutableArray alloc] initWithArray:self.splitViewController.viewControllers];
[arr replaceObjectAtIndex:1 withObject:secondVc];
[self.splitViewController setViewControllers:arr];
DetailViewController is just a normal UIViewController (is this the problem?) I chose red as its background but I am seeing a completely gray area in the detail view after this code is executed.
What surprises me is that viewDidLoad and viewDidAppear functions are called for the DetailView class, but I can't see it on the screen. The self.view.frame is 0,0,768,1024 although all my settings are in landscape mode in storyboard.
I only want to use this in landscape mode, I don't need a generic solution.
What is the most basic way to change the detail view of a split view controller? I have looked at Apple's MultipleDetailViews but that felt like overkill since most of the code in it is about responding orientation changes, like hiding the master vc etc.
I suspect your problem is using alloc init to instantiate secondVC -- that would work if you made your controller's view in code, or in a xib with the name "DetailViewController". Since it appears that you're using a storyboard, then you should be using,
DetailViewController* secondVc = [self.storyboard instantiateViewControllerWithIdentifier:#"secondVC"]; // be sure to use this same identifier in the storyboard
In storyboard, select the view controller. On the right side, go to "Simulated Metrics" and pick "Detail" for "Size". As for the color, try setting it in viewDidLoad.

Present Modal View Controller from inside Popover View

So in my universal app I have a section where a person can look at an existing list of notes from our system (retrieved through a simple web service) and then also create a new note if they want. So for the iphone it's pretty simple layout, a TableViewController for displaying the list with a "Add" button on the NavigationBar that presents the modalview for adding the new item. On the iPad though, the same layout has a lot of wasted space so I opted to go with the popOver method to show the list in a popOver and then let them add from there. My problem is that when the user clicks on the Add button within the PopOver view, the modal view comes up full screen instead of just coming up within the popover view. Here's the code I have so far:
-(void) AddButtonPressed:(id)sender {
NewNoteVC *newNote = [[[NewNoteVC alloc] initWithNibName:#"NewNoteVC" bundle:nil] autorelease];
newNote.defaultClientID = defaultClientID;
UINavigationController *navCon = [[[UINavigationController alloc] initWithRootViewController:newNote] autorelease];
if ([isPopOver isEqualToString:#"YES"]) {
[navCon setModalInPopover:YES];
[self.navigationController setModalInPopover:YES];
[self.navigationController presentModalViewController:navCon animated:YES];
}
else {
[self.navigationController presentModalViewController:navCon animated:YES];
}
}
The "isPopOver" string is just a placeholder sent from the previous screen that called this TableView (I know I can switch this to a boolean for better performance I just put this together real quick to try it out). I know I messed up somewhere, I just don't know what setting I need to get this working correctly.
You need to define the view controller's modalPresentationStyle to be "current context".
navCon.modalPresentationStyle = UIModalPresentationCurrentContext;
This will result in modal view controller filling the popover like the popover's root controller.
Try using the presentViewController:animated:completion: instead of presentModalViewController:animated: and set self.navigationController.definesPresentationContext = YES

Adding a child view controller and changing its label

I got a view controller named IntroViewController in my storyboard and I want to add this as a child to another view controller like this:
IntroViewController *introViewController = [self.storyboard instantiateViewControllerWithIdentifier:#"View1"];
[introViewController.textLabel setText:#"test"];
[self addChildViewController:introViewController];
On the IntroViewController I've put a label named textLabel on it in the storyboard, if I run the program it works and shows me the view controller, but the text doesn't get changed. Any idea how I can fix this?
When you instantiate a view controller from a storyboard, the view is not loaded until it is actually presented on screen. At the point in your code you have posted introViewController.textLabel is nil.
One option you could do is add a property to your IntroViewController class and instead set that:
introViewController.initialText = #"test";
Then, inside -viewDidLoad of your IntroViewController the label will be instantiated so you can make the call:
[self.textLabel setText:self.initialText];
It is also worth noting that most of the time it would be recommended to have a view controller be the one to set values on the views it owns, rather than some other view controller.

IOS Switch view and storyboard not works

I have a problem with switching views. I'm using a simulator with xcode 4.2
Storyboard contains:
NavigationController (initial view controller)
UIViewController which has relationship with the navigation controller
UIViewController (paired with my custom class: ViewEntryImageController) which hasn't got any relationship. Contains a button, a bottom toolbar with some toolbar button.
User come into the UIViewController, where he can see a ScrollView and in ScrollView some images.
Images has a gesture:
UITapGestureRecognizer *recognizer=[[UITapGestureRecognizer alloc]initWithTarget:self action:#selector(openEntryImage)];
[image addGestureRecognizer:recognizer];
[recognizer release];
The openEntryImage function:
(IBAction)openEntryImage
{
ViewEntryImageController *controller=[[ViewEntryImageController alloc]initWithNibName:nil bundle:nil];
controller.modalTransitionStyle=UIModalTransitionStyleCrossDissolve;
[self presentModalViewController:controller animated:YES];
[controller release];
}
When I try to tap the image, the openEntryImage works as well (the effect is correct), but I don't see my ViewEntryImageController view and my buttons, I'm only see a black window.
I try to put a NSLog line into the ViewEntryImageController viewDidLoad function, and it works, so what is the black window and where is my view controller?
When I try to use pushViewController, on the new view I found a navigation toolbar with a back button, but no other controls.
I tried another version, I created a UIViewController class, but now with a xib file. I used it instead of ViewEntryImageController and it works. Why?
I want to use this controller in storyboard too.
The ViewEntryImageController class by itself has no information about how to build the dialog. But you can instantiate your view controller on your own from the storyboard:
UIStoryboard *myStoryboard = [UIStoryboard storyboardWithName:#"StoryboardFileName" bundle:nil];
ViewEntryImageController *controller = (ViewEntryImageController *)[myStoryboard instantiateViewControllerWithIdentifier:#"ViewEntryImage"];
This assumes a storyboard name of StoryboardFileName and that the view entry image controller has an identifier of ViewEntryImage set in the view properties (Attributes inspector, section "View Controller").
Try it like this :
ViewEntryImageController *controller=[[ViewEntryImageController alloc]initWithNibName:#"ViewEntryImageController" bundle:nil];
If you don't use .nib names but rather use storyboards, it's a bit harder. Create a segue from the controller to the ViewEntryImageController controller by holding ctrl and dragging from one view to the other. Click this segue and give it an identifier.
Then use the [self performSegue:#"identifier"]; function to present the next view.

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