The main functionality of my app is controlled by a UITabBarController. However, I need to load a View that has a UINavigationController. When I return to my UITabBarController using
self.tabBarController.selectedViewController = [self.tabBarController.viewControllers objectAtIndex:0];
My UITabBarController no longer responds to clicks. It seems like the View does not have focus.
However, if I use this code to switch back to the UITabBarController:
[window addSubview:tabBarController.view]
My buttons will respond. I feel like "addSubview" is less efficient because I never remove the view from the window and therefore it must be adding a second copy of the view to the stack. Am I correct? Is there a way to use the first method and make my buttons respond? Please let me know.
It sounds like maybe you're presenting the Nav Controller incorrectly. You definitely shouldn't be adding views directly to the window. You want to present it using
[myTabBarController presentModalViewController:myNavController animated:YES];
When you're done with the nav controller you dismiss it with
[myTabBarController dismissModalViewControllerAnimated:YES];
and everything should work.
BTW, this is all documented in the docs for UIViewController and the "View Controller Programming Guide for iPhone OS" document.
Related
I would like to combine UITableView and UINaviationController in an app but as a newbie most apps I've seen just send you straight to the results view (UITableView). But, I guess a "normal" search application does not assume you have the results on the first screen. There should be a search form on first screen with input fields and a button that triggers the search process and show some results and navigation.
So, I'm just trying to replicate this normal behaviour in my app. I've already made the search form (no navigation shown on it, of course) and a seperated View called "ListingViewController" with its related View and containing a UITableView and where I think I should add the Navigation...The next idea will be to make a DetailViewController and possibly and ListingMapController to show the listing in a GoogleMap.
So, where I'm stuck at is how to add this Navigation Controller ?
Some suggested me to add it in the SearchViewController delegate...
But I don't want a navigation on search form of course...
Some suggested me to open the Navigation controller modally...
But, I"m also planning at adding a Tab Bar to allow user to see other informations (like About,etc...) and with a modal Nav controller I don't know if they will still see the bottom Tabbar...
Any suggestions? What do you think is of best practices especially to avoid my app of being rejected by Apple?
Thx in advance for reading and helping!
Stephane
You could init the navigationController with your View Controller as the root view Controller. Then hide the navigationBar (if you need to). You would then add the navigationController.view as the subview. This will basically look like the original view controller. Then you can pushViewController: animated: to push the results view Controller.
So, for example in your AppDelegate (or in the proper view controller):
Create a property and ivar for a UINavigationController and hook up its outlets in interface builder. Then set your search controller as the root view controller for the nav bar, and add it as a subview.
MySearchViewController* searchController = [[MySearchViewController alloc] init];
self.myNavigationController = [[UINavigationController alloc] initWithRootController:searchController];
[searchController release];
self.myNavigationController.navigationBarHidden = YES;
[self.window addSubview:self.myNavigationController.view];
[self.window makeKeyAndVisible];
Then of course in your searchController, you would simply say:
ResultsViewController* myResultsViewController = [[MyResultsViewController alloc] init];
//You may want to create another init method and pass in some arguments like an array:
// [[MyResultsViewController alloc] initWithResults:results];
then push the viewController
//This is in your search controller class
[self.navigationController pushViewController:myResultsViewController Animated:YES];
[myResultsViewController release];
from the results viewController, to get back you pop the view controller off of the navigationController view controller's stack.
//In results view controller perhaps in some IBAction for a back button:
-(IBAction)backButtonPressed:(id)sender
{
[self.navigationController popViewControllerAnimated:YES];
}
I am designing an iPhone App wherein I would like there to be a main screen. I then want users to be able to hit an info button in the bottom right of this screen and enter an entirely different interface that will handle options and various forms of data display.
After some research on View Controllers in Apple's documentation, I have determined that I definitely want to use a modal view when the info button is pressed. My problem, though, is that the interface that fits best is a UITabBarController. I'd like to have a tab in my UITabBarController that represents the main screen and, when touched, will tell the main screen to dismiss the UITabBarController.
I have seen quite a few examples on the web where people add custom view controllers with buttons that trigger the modal view dismissal to tabs on the UITabBarController, but I would like to entirely avoid displaying an extra view. As soon as the user touches the main screen tab, I'd like the modal view to dismiss. I have already experimented with approaches that placed the main screen in the UITabBarController, and was not satisfied, so I'm hoping somebody out there is familiar with the rare modal UITabBarController design and can offer me some guidance.
Is this at all possible? If not, how can I accomplish the same interface flow in a different way?
I haven't tried this yet, but is there a way I could set the UITabBarController up with an empty UIViewController to represent the main screen and call on a UITabBarControllerDelegate to send the dismiss message to the main screen before the empty view appears?
Ok, I figured this out. I admit this is probably not the most orthodox UI design, but I think it does make intuitive sense... somebody should probably link me to the Apple UI guideline that this violates, though.
The following code will allow a user to press an info button that will animate the presentation of a modal UITabBarController. In this example, the UITabBarController has only one tab and the tab bar has not been set up with icons or titles. Once in the modal view, the user can click the first tab in the bar and the modal view will be dismissed. (This logically means that you'll want to tell the UITabBarController to start at an index other than the first.)
- (IBAction)infoButtonPressed
{
UIViewController *mainScreen = [[UIViewController alloc] init];
NSArray *viewControllers = [[NSArray alloc] initWithObjects:mainScreen, nil];
UITabBarController *tabBarController = [[UITabBarController alloc] init];
tabBarController.viewControllers = viewControllers;
//This means that "self" needs to implement the UITabBarControllerDelegate protocol
tabBarController.delegate = self;
[self presentModalViewController:tabBarController animated:YES];
[mainScreen release];
[viewControllers release];
[tabBarController release];
}
- (void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController
{
if (viewController == [tabBarController.viewControllers objectAtIndex:0]) {
[self dismissModalViewControllerAnimated:YES];
}
}
I am now, however, getting a warning about two-stage rotation animation:
Using two-stage rotation animation. To use the smoother single-stage animation, this application must remove two-stage method implementations.
Using two-stage rotation animation is not supported when rotating more than one view controller or view controllers not the window delegate
Preliminary research said that it was because I was using a UIImageViewController to display a background on my mainScreen view, but I have since changed that to UIColor initWithPatternImage. Anybody know how to get rid of the warning-- or if it even matters to ignore it?
Sounds like a confusing (or at least unusual) user experience. Tabs are expected to be the apps main navigation level.
You should consider showing the sections in a segmented button or in a vertical list with back navigation (e.g. The preferences app)
Still learning Obj-C slowly... forgive the dumb questions...
On my 1st XIB I have the App Delegate, Nav Controller and several view controllers. Along with that I have several buttons that calls a 2nd or 3rd or subsequent XIB.
The subsequent XIBS all have buttons which display views.
So on the 2nd+ XIB I have configured it in the .h as an UIViewController however I am guessing I need to make it something else like the primary .h is an AppDelgate.
So right now the XIB wants the view set, but I don't want it to go to a view, I want it to go to the view controller... I think??
Maybe I am still going about this all wrong. I need the primary menu to call the next menu (2nd XIB) which in turn calls various views. In my Java Android app I have about 70 classes, and guess and about 45 views so I am guessing again that I do in fact need the multiple XIBS.
So the question is how do I set up the additional XIBs? Are they AppDelegates or what?
Does that change the way I call the 2nd XIB?
The XIBs or the UIViews (or it's subclasses) are just the facial make up.
For the actually programming part, you deal directly among the "controllers" classes for these views.
View controllers that you make can have an XIB attached to them. But the behavior of how and when the view is shown or hidden, is all handled by the view controller itself.
So to come to the point, if you want to have a navigation bar on the top of you app (assuming that it's a simple app wanting to show many views with a navigation bar):
Create a UINavigationController instance in your applicationDidFinishLaunching: method in the app delegate:
// Assuming that mainViewController is the first controller + view for your app.
navigationController = [[UINavigationController alloc] initWithRootViewController:mainViewController];
[window addSubview:navigationController.view];
This will automatically add a navigation bar to your views. You don't need to add them manually in XIB or anywhere else. Now how you draw/implement mainViewController, is up to you.
When you want to show another view from within mainViewController, you should call:
AnotherViewController *anotherViewController = [[[AnotherViewController alloc] init] autorelease];
[self.navigationController pushViewController:anotherViewController animated:YES];
This will "push" your new view (from anotherViewController instance) into your navigation structure, which will automatically add a back button on the top.
Hope this helps clear the scene of how it works, a bit.
If you have doubts, comment about it. Have a great day!
This is the situation:
I have a tab bar with 2 tabs. Tab01 and Tab02.
In Tab01 I have a button which pushes repVC:
repVC.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
[self presentModalViewController:repVC animated:YES];
[(UIViewController *)[tabController.viewControllers objectAtIndex:0] setView:repVC.view];
[repVC release];
Inside repVC I have another button which pushes an MFMailComposerViewController:
MFMailComposeViewController *mail = [[MFMailComposeViewController alloc] init];
[self presentModalViewController:mail animated:YES];
[mail release];
The problem is: when mailView is shown(in Tab01) and I click Tab02, then back to Tab01, the mailView is hidden and even if I click the email button again, the view won't be presented.
So what I have is: Tab01.view -> repVC.view -> mail.view
For repVC, I use this line when I push the view so that even if I go switch tabs, that view will still be activated:
[(UIViewController *)[tabController.viewControllers objectAtIndex:0] setView:repVC.view];
But I can't do the same for mail because tabController is declared in another class which I cannot import. So I can't access the tabController and set the view for Tab01.
Hope the edit helped the understanding.
Hmm,
I still would suggest to use a Navigationcontroller. Would make things way easier, is conform to apple guidelines and suggestions and is pretty fast implemented. (Just create a Navigationcontroller, put the View of Tab1 as main view and hand it over to the TabbarController. Then for the mailView use [self.navigationController pushViewController:mail animated:YES]; Then the navcontroller "saves" the present view for you when u switch tabs)
But if for some Reason you have to use a modalViewcontroller you could either just deactivate the tabbar while the ModalView is shown or try to implement a switch or a simple if...else case in your ViewWillAppear where u check what screen to load.
Then Clean out the Window and load the right screen.
Hope you get the idea of what I mean, sometimes my way of writing seems to confuse people. ^^
A little more information would be great.
How did u set up your TabbarController?
How do u push the new view? Within a UINavigationController? If not, then do it with a navController, he should save the actual state of view and your problem should be solved.
If u already use a navController please post your ViewDidLoad and ViewWillAppear of the Viewcontroller of Tab 1
As #Amandir points out you could probably solve your problems by using a UINavigationController. I get a feeling that you are trying to abuse the modal view controller concept a bit and that's why it doesn't work as you expect. When you use presentModalViewController:animated: the intention should be that you are displaying a view that is modal, i.e. the user must interact and dismiss the modal view before she can continue.
What the paragraph above means that when you present a modal view controller it shouldn't be possible to use the tab bar. Since you are using the word push I'm guessing that you would like change the view of Tab01 while still being able to use the functionality of the tab bar. The problem is that there isn't any built-in method of pushing view controllers besides UINavigationController. persentModalViewController:animated: should only be used in case where you want a modal view, which on the iPhone means a full screen view.
The easiest way would probably be to use an UINavigationController and hide the navigation bar. Then you would get the functionality I think you are after. The other option is to manually add and remove sub views.
[self.view addSubview:repVC.view];
and
[repVC.view removeFromSuperview];
[self.view addSubview:mail.view];
You can use block animations if you want some fancy transitions.
I've been reading the Head First iPhone Development book and I understand how to get to a new view from a table but how exactly would I be able to get to a new view or view controller, by just simply pressing a button? Is that even possible?
I mean there are some apps where you click a button, not a table cell and it loads a new view. How exactly is that done? If someone could help out a newbie it would be greatly appreciated!
I think what you're looking for is a modal vew controller. THis presents a modal view like you described on top of everything else. If rootViewController is the view controller that is displaying your current view, and myNewViewController the view controller you want to display modally:
[rootViewController presentModalViewController:myNewViewController animated:YES];
There's plenty of examples of this kind of thing on the net, just search for presentModalViewController
Like bpapa said in the comments, it's hard to be specific without code. However, generally what you want to do is:
Build a navigation controller that contains one original view.
Create a button in your original view using the Interface Builder.
Build a callback method (usually defined with IBAction) that is run when the button is pushed.
In that callback method, create a new view and push it onto the navigation controller the same way you would using a table view cell.
Alternately, if you only want one level of hierarchy, you could use a modal view controller; instead of pushing onto the navigation controller in the last step, just present the modal view controller.
The general answer is that you have an object that manages which view controller loads when.
The most commonly used is the UINavigationController. It is a UIViewController that instead of controlling views, controls other view controllers. It works like a simple stack. You push views you want to display onto the nav's controller stack and when you want them to disappear you pop them off.
A common (though sloppy) way of using a nav is to make it a property of your app delegate. Then anywhere in your app you can references it by:
UINavigationController *nav=[[[UIApplication sharedApplication] delegate] navigationController];
The view controller for the first the user sees is held in the nav's topViewController property. If you want to load a view based on a user action in the topViewController.view, you would have something like this:
- (IBAction) loadNextView:(id) sender{ // Action called by a a UI event such as a button press.
UINavigationController *nav=[[[UIApplication sharedApplication] delegate] navigationController];
UIViewController *nextViewController=...// load from nib, connect with IBOutlet, create programmatically
[nav pushViewController:nextView animated:YES];
}
The first view disappears to be replaced by the next one. To return to the first view, you have a method in the next view controller like so:
- (IBAction) unloadSelf:(id) sender{ // Action called by a a UI event such as a button press.
UINavigationController *nav=[[[UIApplication sharedApplication] delegate] navigationController];
[nav popViewControllerAnimated:YES];
}
... and the nav returns you automatically to the previous view regardless of what that view was.
When you first start out, especially if you use Interface Builder, the structure of the app is largely hidden. Behind the scenes all view controllers and their views exist in a hierarchy of some kind that leads back up to the app delegate. You should train yourself to think in hierarchal terms even if it is not immediately obvious how that hierarchy is constructed.