Fairly new to iPhone app development, so this might be really obvious (if so, apologies in advance!)
I'm building an app which has a tab bar. However, when the app first runs and 'launch screen' is shown with 3 UIButtons - each of these buttons points at a view of one of the tabs. What I need to do is:
Close the existing view
Open the selected view
Set the highlighted tab accordingly
This sounds like it should be quite easy, but a few hours of Googling has found nothing!
Thanks for your help,
Kev
Additional:
Sorry - I am using a tabBarController... But instead of immediately launching the tab bar views I'm using the code below to launch the home menu instead.
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
homeViewController *splashView = [[homeViewController alloc] initWithNibName:#"homeView" bundle:nil];
[window addSubview:splashView.view];
// [window addSubview:tabBarController.view];
[window makeKeyAndVisible];
return YES;
}
On the home menu there are UIButtons which need to link to individual tabs... Hope this clarifies...
Cheers!
Oh. Then it gets a bit more complex. What you want to do is basically this:
Add a method to your AppDelegate - (void)showTabBarWithSelectedTab:(NSUInteger)tabIndex. In this method, use tabBarController.selectedIndex to select the correct index, then remove homeViewController's view from the window and add tabBarController's view instead.
In homeViewController, have actions for the buttons that calls the newly created AppDelegate method with the correct tab index.
Generally I would say that this adds a bit too much logic to the AppDelegate. Ideally you'd implement this in a new view controller, surrounding and managing both homeViewController and tabBarController. However, having a UITabbarController inside of another view controller isn't officially supported - although you can get it to work anyway.
it's a bit hard to fully understand your question, but it sounds like you should be using UITabBarController instead of the stand-alone view UITabbar. This is essential reading! Good luck
Related
I'm sure this has been asked countless times, and I've seen similar questions though the answer still eludes me.
I have an application with multiple view controllers and as a good view controller does its own task. However I find myself stuck in that I can't switch from one view controller to another. I've seen many people say "use a navigation controller" but this isn't what I want to use due to the unwanted view elements that are part and parcel to view controller.
I've done the following and have had limited success. The view controller is switched but the view does not load and I get an empty view instead:
- (IBAction)showLogin:(id)sender
{
PPLoginViewController *login = [[PPLoginViewController alloc] initWithNibName:#"PPLoginViewController" bundle:nil];
PPAppDelegate *appDelegate = [UIApplication sharedApplication].delegate;
appDelegate.window.rootViewController = login;
[self.view insertSubview:login.view atIndex:0];
}
Using UINavigationController as a rootViewController is a good tone of creating iOS application.
As i understand unwanted view elements is a navigationBar? You can just hide it manually, setting:
[self.navigationController setNavigationBarHidden:YES];
And about your case, if you want to change you current viewController(targeting iOS 6), you can just present new one:
[self presentViewController:login animated:YES completion:nil];
or add child (Here is nice example to add and remove a child):
[self addChildViewController:login];
Why to set UINavigationController as a root?
1) First of all it makes your application visible viewcontrollers to be well structured. (Especially it is needed on iPhone). You can always get the stack and pop (or move) to any viewController you want.
2) Why I make always make navigation as a root one, because it makes the application more supportable, so to it will cost not so many code changes to add some features to the app.
If you create one (root) viewcontroller with a lot of children, or which presents other viewcontrolls, it will make your code really difficult to support, and make something like gode-object.
Listen to George, UINavigationController is the way to go. Your reasons for not wanting to use it are not valid.
However, the reason your code doesn't work might have to do with the unnecessary line after setting the rootViewController to the login vc.
Per Apple's documentation, setting rootViewController automatically sets the window's view to the view controller's view.
What is the right way to change XIB View which loaded at app start depending on some app settings. Of course I know how to get all settings I need.
In your application's delegate, in the method
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
if(yourSettings)
myViewController = [[MyViewController alloc] initWithNibName:#"FirstNibName" bundle:nil];
else
myViewController = [[MyViewController alloc] initWithNibName:#"SecondNibName" bundle:nil];
self.window.rootViewController = self.myViewController;
[self.window makeKeyAndVisible];
return YES;
}
And that's it. Probably you may want to save your settings in your user defaults so you can load the view properly.
However, I would use 2 different view controllers, as you probably want them to do different things, not just modify some graphics.
EDIT-
Let me see if I understand. You will always load the first view controller and, if some conditions are met, you modally want to present the second view controller that will get dismissed at some point, returning the user to the first view controller. If this is the case, I suggest you move the code in your first view controller, in viewDidLoad or better yet in viewDidAppear, as this view controller will always get loaded. Also this way the user can see that he will eventually go to that view controller. I use something like this in applications the user needs to login to so that it will be obvious for him that he cannot continue until he does login.
I can't say that this is the right way to do it, because it's up to the programmer how he arranges his code, but it would seem to me that the place that controls what view and how it appears belongs in a view controller and not in the delegate, especially considering that your first view controller always gets loaded. It should be up to that view controller to see if it presents the second one or not.
I think this is a pretty common usecase as I have seen it in several apps. But after spending couple of days, I am still struggling with this. I have a structure like the following:
UITabBarController
-- UINavigationController1
---- UITableViewController1
-- UINavigationController2
---- UITableViewController2
Now I have a logout button on UITableViewController2. When I click on that logout button I want all and any viewcontroller to be deallocated, all view unloaded. Basically start fresh like launching the app. I basically want the viewDidLoad on each of those UITableViewController called again.
I tried the following method to be called in my appdelegate when the logout action on UITableViewController2 is taken.
-(void) logout {
for (UINavigationController* ctrl in self.tabBarController.viewControllers) {
[ctrl popToRootViewControllerAnimated:NO];
ctrl.visibleViewController.view = nil;
}
[self.tabBarController.view removeFromSuperview];
[self.window addSubview:self.tabBarController.view];
}
But alas, it does not seem to work?
Any ideas how such a thing is accomplished? Also I see different behaviors in iOS4 vs iOS5 with the visibleViewController. I am not using any modal viewcontroller here. Any gotchas?
Update: I am not using ARC
thanks
mbh
Your for-loop will release and thus dealloc any view controllers that you have pushed onto the respective UINavigationController roots (depending on how many tabs you have), i.e. as these will not have a superview when you pop back to the root of each navigation controller, these are dealloc-ed automatically. These are your UITableViewControllers taken care of.
As for the respective UINavigationControllers, you would need your tabbar-controller to release the old instance. IMHO, this should be done for you when you release the UITabBarController.
This then leaves the UITabBarController itself. I don't think it can be done tbh. Your code will only remove the view, but not dealloc the tabbar controller itself. And as Krishna K points out, you need at least one view controller to reload all others.
Putting the code into the appdelegate makes sense, but you need to ensure that your logout() will not cause a retain on the UITableViewController2 as well as the UITabbarController as it's called from UITableViewController2 somewhere.
One idea to explore, does your AppDelegate hold an instance to the TabBar-Controller which you could release and create a new instance after removing the view from self.window?
// manually create UITabBarController - AppDelegate holds instance
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
mytabcontroller=[[UITabBarController alloc] initWithNibName:#"foo" bundle:nil];
}
- (void) logout {
[self.tabBarController.view removeFromSuperview];
[mytabcontroller release];
mytabcontroller=[[UITabBarController alloc] initWithNibName:#"foo" bundle:nil];
[self.window addSubview:self.tabBarController.view];
}
But as I said, there might be caveats with memory management at this point.
You need to release your view controllers. When their release method is called, that method should include statements to release all of its object's resources (and also dealloc its superclass).
Your rootViewController for both Navigation controllers are their respective TableView controllers. So I don't think popToRootViewController would do anything.
You probably need to reset the data and refresh the views instead of deallocating the views.
I have a program where we are using a navigation controller and need the app to launch to one of two different views. Basically if certain info has previously been entered then we need the app to launch to view A, but if the info has never been entered then we need it to launch to view B. I am having difficulty getting this to work and am wondering what ways if any I could implement this. I am certain it needs to be done in the app delegate but I am not sure how. Thanks in advance!
Implement the following method in your app delegate.
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
[window makeKeyAndVisible];
if(condition) {
[window addSubview:[mainViewControllerA view]];
} else {
[window addSubview:[mainViewControllerB view]];
}
}
There you can choose which view to load depending on your condition.
From your question, it sounds as though your UINavigationController is defined inside a XIB along with your root view controller. In that case, you will need to load the appropriate view from within application:didFinishLaunchingWithOptions: of your App Delegate. From there, you can set the first view controller for the UINavigationController using setViewControllers:animated:.
I have met this issue and solved it.
In you navigation controller build a container view.
Then depending on your conditions you decided what view to put in the container. You might have built these two views beforehand. Then, you can add the view into the container view.
I think the "Elements" sample has an example of the container view.
I have a window within an iPhone application, which is displayed modally to allow the user to enter their settings for a web service upon 'first run'.
The text fields have helper text set, and when you tap them the keyboard shows and allows you to enter text.
Unfortunately the text fields do not clear the helper text, show the edit caret or show the text being entered (as in the screenshot below).
Any suggestions?
The window is being displayed with [self presentModalViewController:<controller_name> animated:YES];, which may or may not be the cause of this issue - when I run the UI via the Interface Builder 'test' application the text boxes respond like normal.
Clear when editing begins has been set for both fields.
Thanks in advance!
Edited: More information
After the info Bart Gottschalk provided I thought I should add some more information. First, the application is a Navigation Based Application.
Secondly, the test app Bart recommended worked fine, so that takes the modal window and the view out of the equation.
Third, I was presenting the modal view when the -(void)viewWillAppear... delegate method was being called - which may very well be the wrong place... however I'm not 100% sure if I should be presenting the modal view from within the didFinishLaunchingWithOptions of the App Delegate...
(this is happening on Simulator and iPhone 3.1.3)
In Interface Builder did you check the box for "Clear When Editing Begins"? With that checked the text field should clear any value once the use taps to edit which is the behavior I think you're looking for.
You can also set the same property programatically using clearsOnBeginEditing if that is convenient in your code.
My guess is that you've done this and it's not behaving as you expect. Just checking on this as a first step in helping you debug.
Also, does this happen in both the Simulator and on a testing device?
Bart
Edited Below...
This seems strange. Let's strip away everything but the basics of presenting a modal view when the application starts and see what happens.
I've recreated the most basic app (that I know of) to test presenting a modal view controller at launch and verify that field editing works fine. What happens for you when you do the same/similar in a new project?
Here is what I'm doing:
1) Create a new view-based app in Xcode called "ModalViewTest"
2) Create a new UIViewController with xib called ModalViewController
3) In ModalViewController.h add a method
-(IBAction)closeModalView;
4) In ModalViewController.m add the method implementation as
-(IBAction)closeModalView {
[self dismissModalViewControllerAnimated:YES];
}
5) In the ModalViewController.xib create two text fields and set the placeholder text for each to abcd1234 and confirm that "Clear When Editing Begins" is checked.
6) In the ModalViewController.xib add a button "Close" and set Touch Up Inside to fire "closeModalView"
7) In the application delegate (ModalViewTestAppDelegate) add the following import
#import "ModalViewController.h"
8) In the application delegate (ModalViewTestAppDelegate) applicationDidFinishLaunching add the following after the line containing [window makeKeyAndVisible];
ModalViewController *modalViewController = [[ModalViewController alloc] initWithNibName:#"ModalViewController" bundle:nil];
[viewController presentModalViewController:modalViewController animated:YES];
9) Save everything
10) Build and Run this new app
Does editing of the text fields work as expected? If yes, what is different about how you are building and presenting your modalView? If no, then we'll need to dig further to determine what is going on in your environment.
Second Edit Below...
When creating a navigation-based application I did the following to present the modal view at application start. Does this work for you in both your test app as well as your real app?
- (void)applicationDidFinishLaunching:(UIApplication *)application {
// Override point for customization after app launch
[window addSubview:[navigationController view]];
[window makeKeyAndVisible];
ModalViewController *modalViewController = [[ModalViewController alloc] initWithNibName:#"ModalViewController" bundle:nil];
[navigationController presentModalViewController:modalViewController animated:YES];
}
Well, I just figured it out, but honestly without the persistence and awesome help from Bart it would have taken much longer and been much more frustrating.
It turns out the problem was that I was using a Window instead of a View in the XIB file. This was why when showing the modal view within the Navigation controller it wouldn't display properly (i.e. only a white screen) and why the UITextField would not work properly when showing the view from the RootViewController.
So, to recap - modal views should have UIView, not UIWindow in the XIB/NIB File.
Thanks for your help Bart!
I have the same problem but in iOS7 only. I solved it by changing the tint color of textField to blue in the Storyboard