I implemented a custom tab bar controller as a set of buttons each one related to it's own View Controller. I guided on this link http://idevrecipes.com/2011/01/04/how-does-the-twitter-iphone-app-implement-a-custom-tab-bar/ to achieve the behavior. So the relevant part of code is as follows:
- (void) selectedItemAtIndex:(NSUInteger)itemIndex
{
// Get the right view controller
NSDictionary* data = [self.tabBarItems objectAtIndex:itemIndex];
UIViewController* viewController = [data objectForKey:#"viewController"];
// Remove the current view controller's view
UIView* currentView = [self.view viewWithTag:SELECTED_VIEW_CONTROLLER_TAG];
[currentView removeFromSuperview];
// Set the view controller's frame to account for the tab bar (+ 48)
viewController.view.frame = CGRectMake(0,48,self.view.bounds.size.width, self.view.bounds.size.height - 48);
// Se the tag so we can find it later
viewController.view.tag = SELECTED_VIEW_CONTROLLER_TAG;
// Add the new view controller's view
[self.view insertSubview:viewController.view belowSubview:self.tabBar];
//Keep track of current view controller
self.currentController = viewController;
}
So far is working, I can see each view controller in a similar maner to the default TabBarViewController. But then there's a requirement where I need to push a new navigation controller modally (it should take all the application frame) from inside one of the tabBar controllers.
At first glance I tried the following code from within one of the tab controllers:
DetailViewController *detailViewController = [[DetailViewController alloc]init];
UINavigationController *navigationController = [[UINavigationController alloc]detailViewController];
[self presentModalViewController:navigationController animated:YES];
However is not working as expected, first the view is shown below the TabBar and second the new view is not taking in consideration the parent view frame which should be the screen bounds less the tabbar. (0, 48, 360, 412). My detail view controller it's loading content from a nib file.
Well, this is quite obvious since the TabBar Controller is inserting each view below my custom TabBar.
[self presentModalViewController:navigationController animated:YES];
So I tried inserting it directly as a window subview:
[[UIApplication sharedApplication].keyWindow addSubview:navigationController.view];
But, I think this is not okay... there should be a better approach that I can't figure out. So if anybody could give me suggestions on how to correct or improve this navigation system it would be great.
Thanks a lot.
If you are building you app for iOS 5.0 and up you can make use of childViewController. In your custom Tab Bar you can have a containerView and a tabView.
The view of viewController is added to containerView. All the necessary events are generated to the subsequently added viewController if the following methods are implemented correctly
- (void)addChildViewController:(UIViewController *)childController;
- (void)removeFromParentViewController;
More about viewController containment can be found here.
Related
How can one present a UINavigationController such that the view it was presented from is still visible in the background?
My experience is that the UINavigationController will clip anything below its view, so setting UINavigationController.view.alpha will uncover a fixed color background, not the presenting view's content.
Can this be changed?
EDIT
I am not interested in the navigation bar, but the full content the navigation controller manages.
The problem is not the UINavigationController, but the fact that you present it modally. ViewControllers presented modally can never be transparent.
You can fake a modal presentation by adding you UINavigationControllers view as a subview to the main UIWindow.
This example works for me when testing in XCode:
UIViewController *viewController = [[UIViewController alloc] init];
viewController.view.backgroundColor = [[UIColor greenColor] colorWithAlphaComponent:0.35];
UINavigationController *navCon = [[UINavigationController alloc] initWithRootViewController:viewController];
[[[[UIApplication sharedApplication] delegate] window] addSubview:navCon.view];
Of course you will have to do any animated transition yourself, but that should be trivial using animation blocks.
There is now a way to achieve this using the iOS7 custom transitions, this way :
MyController * controller = [MyController new];
[controller setTransitioningDelegate:self.transitionController];
controller.modalPresentationStyle = UIModalPresentationCustom;
[self controller animated:YES completion:nil];
To create your custom transition, you need 2 things :
A TransitionDelegate object (implementing
<UIViewControllerTransitionDelegate>)
An "AnimatedTransitioning" object
(implementing <UIViewControllerAnimatedTransitioning>)
You can find more informations on custom transitions in this tutorial : http://www.doubleencore.com/2013/09/ios-7-custom-transitions/
if you wish this behavior you can not use a UINavigationController, as you say the navigation controller clip the view of the content controller. To do what you want you should add a navigator bar to your view instead, and simulate the actions of the navigation controller. To create a back button similar to the controller read this article
I'm trying to add some navigation controller in my app, it's sth likes:
in my index page view controller, I try to initialize the navigation controller like this:
-(void)viewDidLoad{
...
//allocate a navigation controller.
myNavigationController = [[UINavigationController alloc]init];
myNavigationController.delegate = self;
myNavigationController.navigationBar.hidden = YES;
[self.view addSubview:myNavigationController.view];
[myNavigationController pushViewController:tabViewController animated:YES];
[self presentModalViewController:myNavigationController animated:YES];
}
Here, index page view controller is the root view controller of my app, it's just a common UIViewController here.
[myNavigationController pushViewController:tabViewController animated:YES];
The tabViewController here I've pushed into the navigation controller is a custom tabview controller which makes use of a container view to hold the tab button and also holds an navigation controller for tab switching.
The problem here is:
myNavigationController.navigationBar.hidden = YES;
since I've make the navigation bar invisible, it doesn't show when my custom view controller shows, but when I'd like to switch to some other view controller with the navigation controller and I also want the navigation bar visible:
myNavigationController.navigationBar.hidden = NO;
MyViewController *toSwitchNC = [[MyViewController alloc]init];
[myNavigationController pushViewController:toSwitchNC animated:YES];
The navigation bar would never show any more. I've also tried to put:
self.navigationController.navigationBar.hidden = NO
in MyViewController's viewDidLoad, ViewDidAppear or even in the navigation controller's delegate method, it didn't show the navigation bar neither.
So what's wrong with it? Why I initialized the navigation bar to be invisible at first, it will never show again even I set the hidden flag to be false?
Okay, I've got this fixed by removing the navigation controller container in my index page view controller. This might be a stupid question, since apple've formally stated in the developer document that the navigation view controller should be place as root as possible in the view stack. Since IOS is a closed system, who knows WTH is going on under-beneath except Apple.
I have added a navigation controller inside a viewcontroller thats inside another navigation controller... lol
well anyway because of this structure I have an issue with any views I push to the "sub"navigation controller.. because its only fitting inside the grame of the "parent" navigation controller its pushing the pushed views contents down by about 20/40pxl...
I was wondering how I get stop this from happening.. here are two pictures showing you what is happening.
where the label is clearly centered in Interface builder
This is the code I have so far for this stuff.
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.
// Init the (sub)navigationController
otherNav = [[UINavigationController alloc] init];
// Add this (sub)NavController to the current viewcontroller (which is inside the (parent)navcontroller)
[self.view addSubview:otherNav.view];
// Hide the (sub)NavControllerbar
otherNav.navigationBar.hidden = YES;
// Load a detial view into the (sub)NavController
DetailViewController *detailView = [[DetailViewController alloc] initWithNibName:#"DetailViewController" bundle:[NSBundle mainBundle]];
[otherNav pushViewController:detailView animated:NO];
}
The otherNav is also set up in the .h file for global access in this view.
When the "super" NavigationBar is visible, the self.view.frame.height is:
480-20-44 (actualViewheight-statusbarheight-navigationBarheight).
There are 2 solutions for your problem.
1. For simplicity I would say, if your only problem is to make it centralized.
[self.view addSubview:otherNav.view];
[otherNav.view setCenter:self.view.center];
This will make your label center alligned.
2.Though, if you are using interface builder;
select the xib file.
select the view.
open Utilities.
set the Top bar as Navigation bar.
then the things you will align you will get as it is on device/simulator or what ever you are testing on.
I have a tab bar application and when I display a modal view controller, the content screen is offset by about 20 pixels to the top and left. It looks like this:
I'm presenting this view from the child view controller (detail view) of navigation controller (main view) of the tabview.
When I show the view, I'm hiding the tab bar and navigation bar but status bar is kept visible. Adjusting the view to be centered (through Interface Builder's Simulated Interface Elements->View Mode : Center) and changing the view's frame after a call to 'viewDidLoad' in the controller doesn't seem to shift it.
- (void)viewDidLoad {
// this still doesn't cause it to shift
self.view.frame = CGRectMake(0, 20, 320, 460);
}
What's the way to adjust this so that the content area is shown correctly?
I launch the child view like this:
[detailController presentModalViewController:tvc animated:NO];
The app's view controller hierarchy:
Tab view with two child navigation controllers are created in the app delegate and the nav controllers added to the TabBar's view controllers:
tabBarController = [[UITabBarController alloc] init];
tabBarController.viewControllers = [NSArray arrayWithObjects:tab1ViewController,
tab2ViewController, nil];
[window addSubview:tabBarController.view];
Each view controllers of the tab is created as a NavigationController with 1 view controller:
// MainViewController inherits from UIViewController
[MainViewController *viewController = [[MainViewController alloc] initWithNib..];
tab1ViewController.viewControllers = [NSArray arrayWithObject:viewController];
A detail view controller is launched with 'pushViewController' as a result of some action on tab1ViewController :
DetailController *detailController = [[DetailController alloc]
initWithNibName:#"DetailView"
bundle:[NSBundle mainBundle]];
[self.navigationController pushViewController:detailController animated:YES];
[detailController release];
It's from the detailController that I'm trying to launch the problem controller.
Some things to check right off: is "viewDidLoad" actually getting called?
If so, what is self.view.frame set to after the assignment?
Put an NSLog at the end that prints out the x, y, width, height, and see what's there.
Also, since the trouble vc is modal, it will occupy the entire screen.
"On iPhone and iPod touch devices, the view of modalViewController is always presented full screen."
HTH,
Mike
I am showing a modal view which is a UITableViewController class. For some reason it won't show the navigation bar when I show it. Here is my code:
SettingsCreateAccount *detailViewController = [[SettingsCreateAccount alloc] initWithStyle:UITableViewStyleGrouped];
detailViewController.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
detailViewController.navigationController.navigationBarHidden = NO;
[self.navigationController presentModalViewController:detailViewController animated:YES];
detailViewController = nil;
[detailViewController release];
I thought it was shown by default? If it helps, I am calling this from another class that is also a UITableViewController managed by a UINavigationController. Ideas?
When you present a modal view controller it does not use any existing navigation controllers or navigation bars. If all you want is to display a navigation bar, you need to add the navigation bar as a subview of your modal view and present it as you're doing.
If you want to present a modal view controller with navigation functionality, you need to present a modal navigation controller containing your detail view controller instead, like so:
SettingsCreateAccount *detailViewController = [[SettingsCreateAccount alloc] initWithStyle:UITableViewStyleGrouped];
UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:detailViewController];
[detailViewController release];
navController.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
[self presentModalViewController:navController animated:YES];
[navController release];
Your modal controller will manage its own navigation stack.
Here is one way to display navigation bar for those who are using storyboards, suggested by Apple's Tutorial on Storyboard.
Because a modal view controller doesn’t get added to the navigation stack, it doesn’t get a navigation bar from the table view controller’s navigation controller. To give the view controller a navigation bar when presented modally, embed it in its own navigation controller.
In the outline view, select View Controller.
With the view controller selected, choose Editor > Embed In > Navigation Controller.
On iOS 7 and you just want a navigation bar on your modal view controller to show a title and some buttons? Try this magic in your UITableViewController:
// in the .h
#property (strong) UINavigationBar* navigationBar;
//in the .m
- (void)viewDidLoad {
[super viewDidLoad];
self.navigationItem.title = #"Awesome";
self.navigationBar = [[UINavigationBar alloc] initWithFrame:CGRectZero];
[self.view addSubview:_navigationBar];
[self.navigationBar pushNavigationItem:self.navigationItem animated:NO];
}
-(void)layoutNavigationBar{
self.navigationBar.frame = CGRectMake(0, self.tableView.contentOffset.y, self.tableView.frame.size.width, self.topLayoutGuide.length + 44);
self.tableView.contentInset = UIEdgeInsetsMake(self.navigationBar.frame.size.height, 0, 0, 0);
}
-(void)scrollViewDidScroll:(UIScrollView *)scrollView{
//no need to call super
[self layoutNavigationBar];
}
-(void)viewDidLayoutSubviews{
[super viewDidLayoutSubviews];
[self layoutNavigationBar];
}
I want to share how the accepted solution can be used in projects with storyboards:
The simple approach is to put in a storyboard blank navigation controller before the VC which is to be presented modally, so the relations look like:
(Presenter VC) -> presents modally -> (navigation controller having a controller to be presented as its root).
We've tried this approach for a while and noticed that our storyboards become "polluted" by a large number of such intermediate navigation controllers when each! of them is used exclusively for one! presentation of some other controller, that we want to be presented modally with navigation bar.
Our current solution is to encapsulate the code from accepted answer to a custom segue:
#import "ModalPresentationWithNavigationBarSegue.h"
#implementation ModalPresentationWithNavigationBarSegue
- (void)perform {
UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:self.destinationViewController];
[self.sourceViewController presentViewController:navigationController animated:YES completion:nil];
}
#end
Having this segue in our project we do not create intermediate navigation controllers in our storyboards anymore, we just use this ModalPresentationWithNavigationBarSegue like:
Presenter VC --> Presentee VC
I hope that this answer will be helpful to people who like to avoid unnecessary duplication in their apps storyboards.
I just wanted to add something to what #Scott said. His answer is definitely the easiest and most accepted way of doing it now with Storyboards, iOS 7 and 8... (and soon, 9).
Definitely adding a view controller to the Storyboard and Embedding it as described by #Scott is the right way to go.
Then, just add the segue by control-dragging from the source view controller to the target (the one you want to show modally), select "Present Modally" when the little view appears with the choices for the type of segue. Probably good to give it a name too (in the example below I use "presentMyModalViewController").
One thing that I needed that was missing is #Scott's case is when you want to actually pass on some data to that modally-presented view controller that is embedded in the navigation controller.
If you grab the segue.destinationViewController, it will be a UINavigationController, not the controller you embedded in the UINavigationController.
So, to get at the embedded view controller inside the navigation controller, here's what I did:
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([segue.identifier isEqualToString:#"presentMyModalViewController"]) {
// This could be collapsed, but it's a little easier to see
// what's going on written out this way.
// First get the destination view controller, which will be a UINavigationController
UINavigationController *nvc = (UINavigationController *)segue.destinationViewController;
// To get the view controller we're interested in, grab the navigation controller's "topViewController" property
MyModalViewController *vc = (EmailReceiptViewController *)[nvc topViewController];
// Now that we have the reference to our view controller, we can set its properties here:
vc.myAwesomeProperty = #"awesome!";
}
}
Hope this helps!
If you only need a NavigationBar, you can add an instance of UINavigationBar and assign BarItems to it.