How to switch views in storyboard (programmatically and with IB) - ios

After struggling a bit to find the right answer for my work, and after going through numerous posts on the net (and some hours to sort out why those posts didn't work) I thought it would be helpful with a short and definite answer on how to do this in ios7+
So, using Interface builder you want to create a Seque between your view controllers that you want to transition between. All the posts Ive seen does this Ctrl-dragging from the views inside the work area in IB. You need to take use of the view hierarchy structure to the left, or it might not let you create the seque!
Choose "Present modally seque" (or you probably wouldn't be reading this).
Now go to the attributes inspector for the seque. Here you need to fill in "Identifier" for your seque.
Then go to your code and use this method to perform the transition:
[self performSegueWithIdentifier:sequeIdentifierString sender:self]
Voila!
You can also easily do the transition without using seques.
Use this code (remember to go to your view controllers attribute inspector and fill out the Identifier!):
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
MyViewController *myVC = [storyboard instantiateViewControllerWithIdentifier:myVCIdentifierString];
[self presentViewController:myVC animated:YES completion:nil];
I hope this is useful, it sure would have been for me.
Best of luck!

Related

Scenes - Use dedicated Storyboards depending iPad or iPhone

Apple now wants us to use "scenes" rather than windows and screens to display content in for iPad and iPhone. Now having added the support for scenes I seem to have lost the ability to target iPad or iPhone with Storyboards?
I set my scenes inside plist like this:
This was copied from a new project, as Apple seems to have forgotten to document how to add scenes to an existing app. Another example of Apple not documenting sufficiently!
Now I seem to have lost the ability to use different storyboards for iPad from iPhone.
Whilst I could use the same storyboard for the iPad that I use with the iPhone my app looks better with the dedicated interface I have for the iPad because I use the extra real estate it offers to give a better end user experience. iPhone is fine, the interface is best suited to a small display but looks barren on an iPad.
Help!
Now I seem to have lost the ability to use different storyboards for iPad from iPhone
It's quite simple (and, as you say, not documented). You need two completely separate scene manifest entries in your Info.plist, i.e. UIApplicationSceneManifest and UIApplicationSceneManifest~ipad. They just specify different UISceneStoryboardFile values, and you're all set just as before scenes came along.
There may be a better way to do this, but searching I couldn't see anybody else covering this. Therefore, I'm giving my solution which has been accepted by the App Store here for others to review, use, improve upon, and most importantly, not waste any time on a goose chase looking for a solution that may not exist!
The way I got around this was to add another storyboard and view controller just to handle the decision if it's a iPhone or iPad, and then immediately load up the targeted storyboard. I called this "entry decision". The only issue was when closing the subsequent views you have to ensure that you're doing it correctly or you'll end up back at the "entry decision". And with a blank view, your end user could be stuck. Therefore, to ensure a user can never really be stuck I put buttons in that view so they can manually navigate should it show up if there's a change by Apple further down the line that we don't know about. Best to cover it now.
Step 1, create an new storyboard, "entry decision":
Because I'm a nice person I explain to the user it's an error and apologise. I also give them two buttons, iPad and iPhone. In theory, if all goes well, the end user will never see this, but at no cost to us it's better to cover this possibility.
Step 2, as soon as the view controller is loading get it to move to the right storyboards we actually want.
-(void)viewDidLoad {
// Need to decide which storyboard is suitable for this particular method.
// Loading from class: https://stackoverflow.com/questions/9896406/how-can-i-load-storyboard-programmatically-from-class
if ( [UIDevice currentDevice].userInterfaceIdiom == UIUserInterfaceIdiomPad )
{
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard_iPad" bundle:nil];
ViewController *detailViewController = [storyboard instantiateViewControllerWithIdentifier:#"myViewController"];
[self.navigationController pushViewController:detailViewController animated:YES];
}
else
{
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
ViewController *detailViewController = [storyboard instantiateViewControllerWithIdentifier:#"myViewController"];
[self.navigationController pushViewController:detailViewController animated:YES];
}
}
- (IBAction)pickediPhone:(id)sender {
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
ViewController *detailViewController = [storyboard instantiateViewControllerWithIdentifier:#"myViewController"];
[self.navigationController pushViewController:detailViewController animated:YES];
}
- (IBAction)pickediPad:(id)sender {
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard_iPad" bundle:nil];
ViewController *detailViewController = [storyboard instantiateViewControllerWithIdentifier:#"myViewController"];
[self.navigationController pushViewController:detailViewController animated:YES];
}
There's nothing really special about this as it is a mix of detecting which device and then loading the right storyboards. And for full disclosure, I include a reference back to the original code I used for loading those storyboards.
The additional two methods are just the button presses, shown here for completeness.
Step 3, update the scene configuration inside plist to target Entry Decision instead of Main.
You're targeting a different storyboard, hence this needs updated.
Step 4, returning back to your main screen.
In my app, I have a welcome screen, and then table views or other views depending on which it is. Some types work find without any issues, but as I'm using a navigational controller I need to return correctly. Therefore, this one works best for the final "back" command to the main screen:
[self.navigationController popViewControllerAnimated:YES];
Other options either went back to the Entry Decision (the fault we covered just in case) or did nothing:
[self.navigationController popToRootViewControllerAnimated:YES];
[self dismissViewControllerAnimated:YES completion:NULL];
And that is how I'm able to use my existing storyboards, which have been tweaked perfectly for iPhone and iPad over the years of this app's life, and still be able to support Apple's desire to move to scenes. My app needed to use scenes for another purpose, therefore I had no option but to go this route. I went through many attempts to try and trap the scenes as they're getting loaded, but the initial scene seems to get loaded without you, the programmer, getting any options in how it should be or which one to use. You need this pre-view controller to give you that functionality back, and it is one solution which is active in the App Store now.
Be nice.

Call a method from a previous story board

I have the mainstoryboard + viewcontroller
When I press a button on the mainstoryboard it will show another storyboard.
When I press a button in the new storyboard I want to call a function of the mainstoryboard.
How can I make this happen?
You can grab the storyboard and instantiate a viewController from it like this:
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"yourStoryboardName" bundle:nil];
YourViewController *viewController = [storyboard instantiateViewControllerWithIdentifier:#"yourViewControllerIdentifier"];
But if you require a function that contains the context of the previous view controller, you should keep a reference to it and just call your methods directly from there. You can also use the presentingViewController property to access the view controller that started the modal presentation. Or if using a navigationController you can use the viewControllers property to access previous viewControllers in the stack.
The comment of Abizem gave me the right tag to search for.
'Protocols'.
I found a very good explanation here on stackoverflow.
Look there:
How to access a previous story board.
Just have a look at the answer of Matt Price. Very nice explanation!

Contained UIViewControllers - should I use .xib or the storyboard?

I'm making an app that will have a VC doing a similar job as a UITabBarController and I'm using
[self addChildViewController:theViewController];
// [self addSubview ... etc
to put a custom UIViewController's view as a subview of my main (root) VC.
So my question is, which is the correct way to instantiate a VC and not have to build it's UI programatically - from a .xib file, or from a storyboard?
With a xib:
UICustomViewController *controller = [[UICustomViewController alloc] initWithNibName:#"customVC" bundle:nil];
With a storyboard:
UICustomViewController* child = [self.storyboard instantiateViewControllerWithIdentifier:identifier];
I believe .xib files are old stuff and storyboards are the way to go, but I also read this article, which suggests that using a storyboard to do this is a bit hacky. I don't know, any thoughts?
there is nothing any major difference in both way , they are same . but in many other angle storyboard is the straight way, there is nothing any hacky
If you want the child view controller to be present when the app opens, you can do it in a storyboard without any code at all. Add a container view to your root vc, and you will automatically get a view controller embedded in it.

Moving from one view to another iOS

I'm relatively new to iOS development. I am to move from one viewController to another I use a modal segue transition on button click. This is a game so i want to allow the user to click images to essential move the the app menus.
I have a main page that displays several images, on clicking one i want to be able to move to another view. Currently doing this with a modal segue is causing odd problems with my touchesEnded event where if, for example, i navigate to a page 3 times the touchesEnded event is fired 3 times.
Is there a better way for me to do this or am i just missing thing fundamental?
Thanks
Yes, I think you must make the the navigation controller your root view controller then push views accordingly
UINavigationController * nav = [[UINavigationController alloc] initWithRootViewController:YOUR_BASE_CONTROLLER]
self.rootViewController = nav;
this is in your app delegate.
Then in your action method
[self.navigationController pushViewController:secondViewController animated:YES]
Im assuming you are using the Storyboard to link VCs using segues.
Modal segues are great for simple transitions but really seem to limit what you can accomplish when they are just linked through SB. Ive found that creating an IBAction that includes the following for a VC segue will allow you to not only control your segues more efficiently but also allow you to have a clearer view of what is actually occurring during the transition.
-(IBAction)goToVc:(id)sender{
//Other code to take place during the segue here
//This will identify the Storyboard in use
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
//This will identify the View Controller to switch to
SecondViewController *vc2 = [storyboard instantiateViewControllerWithIdentifier:#"SecondViewControllerID" ];
[self presentViewController:vc2 animated:YES completion:NULL];
}
Every time you perform a modal segue, you lose the UINavigationController that you were previously using. What you need to do is embed a UINavigationController in the view that you are performing a modal segue to.
Check out a question I answered the other day to help you visualize more clearly what I'm talking about.

How to load a scene in a storyboard from a view controller

I am developing an application that loads a web page (using UIWebView) using Storyboard (I do know nothing about previous xib neither). I have already created a view controller for that UIWebView and everything works fine. The thing is: since previous versions of iOS don't allow to upload files, I need to make a new view (scene I thought it is called) that allows the user to pick and post a picture. I am able to develop both views separately and they work as expected but now I need to connect them based on event triggered when user wants to post a picture to the server. Using shouldStartLoadWithRequest I can catch that action, then I need to redirect to new view (which contains image picker and a button in order to upload the selected image) if iOS version is below 6.0 but I am really lost when it comes to load the new controller to show that view. Using buttons it is trivial but I don't know how to called inside the code. So far, I have a view controller linked to that scene and I have tried these ways:
WritePostViewController *postViewController = [[WritePostViewController alloc] init];
[self.navigationController pushViewController:postViewController animated:YES];
And even calling the storybard:
UIStoryboard *sb = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
[sb instantiateInitialViewController];
UIViewController *vc = [sb instantiateViewControllerWithIdentifier:#"WritePostView"];
vc.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentViewController:vc animated:YES completion:NULL];
The first approach does nothing and second one shows this error log:
* WebKit discarded an uncaught exception in the webView:decidePolicyForNavigationAction:request:frame:decisionListener: delegate: Storyboard () doesn't contain a view controller with identifier 'WritePostView'*
I have been browsing and reading a lot but nothing solves my problem. For sure this a problem with my not-so-large knowledge about iOS but I am really stuck. I will thank any help.
By the way, I need to come back after posting the file but I could imagine it is the same way opposite direction, right?
If your code is inside a view controller (which it seems to be), you can get the current storyboard with self.storyboard. You also don't need instantiateInitialViewController because, if all your UI is coming from the same storyboard, it has already gone through the loading of the initial controller.
As for the actual error, it's complaining that #"WritePostView" isn't a recognized name for any view controller in the storyboard. Note that what it looks for here is not the class name for the controller but the Storyboard ID for the controller. (Which makes sense since you could have different "scenes" with the same type of controllers.)
Ok, it seems is solved. I just have added a segue between scenes
and then I just need to add this one:
[self performSegueWithIdentifier:#"writePostViewSegue" sender:self];
and it works!. Anyway, I am not sure if it is the way to do it, so if someone knows better, please let me know.
Cheers

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