I have a login page at the beginning of my app that I do not want on the view stack. Is there a way to load my first post-login view after the login without using UINavigatorController?
Is there a better way to be doing this? Should I be using 2 UINavigationControllers? Is there a way to change the RootViewController for a UINavigationController?
Yes, you can change root controller of window. Set window's property rootViewController to new controller and you're done. Don't forget though that first controller (one you are removing) will not receive viewWillDisappear: and viewDidDisappear: messages. Send them yourself before switching controllers if you're interested in them.
You might also look at UIViewController#presentViewController
Related
This is my first app using storyboards/segues, and I'm pretty sure the answer to this is easy, but I'll be as thorough as possible in describing my issue.
I am making a simple app which has a Tab Bar Controller scene and two View Controllers.
My app launches by being sent a URL from another app. The application:openURL:sourceApplication:annotation: method in the app delegate performs some work to determine
which tab to display first, and
what information to display on it.
My goal is to use the performSegueWithIdentifier method (I'm open to alternatives though) from within the AppDelegate to select the tab, and also find a way to send a method to the instance of the view controller created by the storyboard.
Issue #1 is that I can't set an identifier. When I select the tab "relationship" there are no choices available in the Attributes Inspector (it says "Not Applicable"). How do I set a name for this segue? Can I? Or is there some rule under which UITabBarController segues can't be trigger programmatically?
Issue #2 is that I can't find a way to have a pointer to the view controller. Pre-Storyboard I would alloc and init a new view controller and then set it up, but here if I do that, it does not get displayed when my app launches (I think this is because Storyboard is displaying a different instance of the same view controller.)
I know this post is long, but I feel like I'm missing something simple. What is it?
Sounds like you need to have your AppDelegate set the entry point to your storybard.
I'm having trouble to achieve the following using a storyboard:
When setup is not done:
run app -> show settings view controller -> show main navigation controller
When setup is done:
run app -> show main navigation controller
So basically, I want the app to programmatically start with the settings view in certain cases, and otherwise skip right ahead to the main navigation controller.
I did manage to show the settings view with a modal style segue from the main navigation controller, but I don't know how to display it before the main navigation controller is displayed. Any ideas?
By default, the initial view controller from your main storyboard is instantiated and displayed automatically when your app starts up. To prevent this happening you need to remove the UIMainStoryboardFile setting from your info.plist file.
With no default view controller, you are now free to create one programmatically at app startup. See the UIStoryboard documentation. Use +storyboardWithName:bundle: to load the storyboard and then use –instantiateViewControllerWithIdentifier: to create the correct view controller. You will also need to create a main UIWindow and add the view controller's view to it just like you used to do with .nib based UI. Note that without the UIMainStoryboardFile setting a main window is not created for you - read the explanation.
I managed to do it a bit different:
Use a UINavigationController as the initial view controller.
Create a root view controller that will manage the decision of what to load.
Create a Storyboard Segues from the root view controller to the main view and to settings view, and give the segues proper identifiers.
Call the performSegueWithIdentifier with the proper identifier from your root view controller.
Just another solution, hope this helps.
I did something similar to amoshaviv, his advice is sound. I did it slightly different though, and I'll give some more info.
I created a custom MyInitialViewController class, derived from UIViewController, and made this the initial view controller.
In the storyboard file, I created modal segues with appropriate names to all (in my case three) possible 'real' first view controllers.
In the MyInitialViewController class, I implemented the
- (void)viewDidAppear:(BOOL)animated;
method, to first perform the check which view to switch to, and then do the correct
[self performSegueWithIdentifier:#"NameOfSegue" sender:self];
Effectively, this makes the MyInitialViewController nothing more than a switch performed when it's brought into view. I first tried doing this when loaded because I don't care for actually seeing this view, but that did not work, while viewDidAppear does.
To make this visually smooth, I tried the following. In the properties of the segues, I disabled animation. The view I left empty, and I gave it a background color matching to that of the startup image.
My UINavigationController's navigation bar is kind of static. This means, there is no back button, because going back in the stack is done via the first entry of the UITableView the controller holds. The title also always shows the name of the root item.
To achieve this I have added my own custom view to UINavigationController.NavigationItem.titleView
It looks a bit odd if a new controller is pushed in: the old navigation item vanishes, just to get replaced by one looking exactly the same.
Is there a way to prevent this behavior? I want the animation for the content of the controller, so pushing the new controller without animation is not an option.
Add your own UINavigationBar and implement your own delegate and custom animations for the content views.
It sounds like you'll only need one UINavigationItem, so that makes this model easy to manage.
When I switch tabs in my tab bar application, one of my views needs to update because the user may have changed a preference that affects it. It is a UIViewController's view, but when the views switch, the viewDidLoad/Appear methods aren't called. Can this be solved using an NSNotification or any other way? Please give example code, especially for NSNotifications, as I am new to them.
You might want to peek at UITabBarControllerDelegate and tabBarController:didSelectViewController:. There you can determine how to handle the view change and whether you need to update the view based on the possible preference change.
tabBarController:didSelectViewController: you can implement this method in the appdelegate.
you will get the sxact root view controller at which yopu clicked . then you can update that view .
Is there a way to prevent auto-rotation from a view controller when the keyboard is showing?
I don't want to capture the notifications and handle all drawing by hand if possible.
Edit:I found that the root view controller in the chain was preventing the shouldAutorotateToInterfaceOrientation: message from coming down the pipe. Once it was taken away at the root view controller level and left to the sub-view controllers to handle it worked quite well.
Does the editing use a UITextField? If so, have you tried using the UITextFieldDelegate method textFieldShouldBeginEditing: as a place to modify a flag referenced by shouldAutorotateToInterfaceOrientation: ?