So, adding a view that appears over the UINavigationBar in a UINavigationController is easy enough:
self.navigationController?.view.addSubview(testView);
However, getting that UIView to push/transition alongside UIViewController changes in that navigation flow is more tricky. Aside from simply fading the view alpha from 1 to 0 or vice versa on appear/disappear, is there an elegant solution/hack for getting the horizontal position of the view to stay centered, for example?
EDIT: The reason why setting titleView on the UIViewController's navigationItem won't work is because when another view is popping it clips the titleView... (compare this image to the one above)
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I am trying to add subview to UITabBar which should be behind other UITabBar Subviews.
I added the subview like this in my subclass of UITabBarController:
self.tabBar.addSubview(CustomTabBarController.xView!)
and then I send it to back as below:
self.tabBar.sendSubview(toBack: CustomTabBarController.xView!)
Problem is it doesn't go back and always appear infront. Also, even when this is the case, I am able to tap on tabbaritems. Is something wrong with UITabBar properties? or else, What am I doing wrong?
A view that a subview of view A can't be behind view A. Think of a subview as being on the page of it's parent view.
It's also likely that a tab bar does not allow you to add subviews to it. Apple's UI controls are usually built to fully manage their view hierarchies, and the results of trying to insert subviews or otherwise mess with the view hierarchy are often undefined.
If you want a view to be behind another view the two views need to have the same parent view. You need to tell the tab bar's superview to add your new view behind the tab bar:
self.tabBar.superview. insertSubview(CustomTabBarController.xView!,
belowSubview: self.tabBar)
Also note that your use of force-unwrapping is ill-advised
I have many ViewControllers inside one NavigationController. In one of ViewControllers I should show toolBar below navigationBar. If simply add it to ViewController with necessary coordinates I have this:
But here is separator between NavigationBar and ToolBar.
If I set clear background and shadow images and set blur effect for navigationBar it is a problem with different blur effects in navigationBar and toolBar:
So is it resolution when there is no imagesShadow in navigationBar and there is common blur effect?
I resolve my problem. Idea of resolution make NavigationBar and ToolBar fully transparent. Next On every ViewController in place of bars and below them I put UIVisualEffectView with common height of bar or bars. So UIVisualEffectView simply should be the highest subview of rootView of ViewController. And here is a problem in case of using UITalbeViewController UITabBarController and so on. In my situation there was only UITalbeViewControllers. Firstly I try to use this resolution. But I had problems with creating of multiple subviews wile navigation via different ViewControllers. Finaly I restructure storyboard. Every TableViewController I have replaced by ViewController with rootView simple view. TableView was subview of rootView. Also I put there VisualEffectView. I have done it for every TableViewControllers.
Here is a sample of structure:
I think there is there better resolution but currently this is optimal.
I have a simple case where I am pushing a new viewcontroller onto a navigation controller stack. This VC uses a xib and has a UISearchBar that is constrained to the top and left 'container' which in this case is simply the main View.
When I push this VC on the stack the search bar is not seen. This is because the nav bar rests on top taking up the first 50 or so y points of the device screen. (starting after the status bar presumably).
If I set the top container auto-layout constraint to 50, or some y-offset sufficient to counteract the height of the nav bar, I will see the search bar.
I am working on a project where I am pushing VC's onto a nav stack of a UINavigationController I did not create. I am wondering what reasons could lead to this (what i would call buggy) behavior. My understanding was that any viewController in a navController would have it's main view's frame adjust in the presence of nav/status/tab bars. What can I do to ensure that origin (0,0) starts at screen origin + status bar height + nav bar height? Furthermore, I would also like my VC's mainView's lower bound to end at the top of the tab bar also present on screen. I have looked into various UIView and ViewController properties and have not found a satisfying solution.
If you use xib file for designing your view controller, you should add this code to your viewDidLoad method:
self.edgesForExtendedLayout = UIRectEdgeNone
This line will make your view controller's view is laid out under the navigation bar.
Conventionally, any new UIViewControllers are done on storyboards and some developers hook up segues between the first and second UIViewController. The reason for this is because by implementing a pushing segue, the secondUIViewController over the first one, the second one will inherit whatever properties the first one had (such as navigation bars, toolbar, tabbar) and it shows on the storyboard immediately.
So then it will be easier to work on the second UIViewController knowing how much space to allocate to UINavigation or UITabbar.
If your VC is done on an XIB interface instead of being hooked to the UINavigationController controlled stack of previous ViewControllers, then I am guessing you are not seeing the space that UINavigationBar and UITabBar supposedly takes up on your interface?
Perhaps you could try setting the constraints to begin at 64 points below the Top Layout Guide (to make space for UINavigationBar) and 49 above the Bottom Layout Guide (to make space UITabbar).
I have a UITabBarController which has four tabs. One of those tabs opens a my results screen (a UITableViewController).
On showing this screen, I want to move the UINavigationBar down 20px (to make room for a custom UIStatusBar which I show on all screens).
On all my other screens, I add some code to the viewWillAppear method to change the self.navigationController.navigationBar.frame.origin.y to 20.
but these are all "non-root" screens (i.e. a pushed view with a back button).
However on THIS screen the UINavigationBar must be initially visible, even though it is the root view. I use the same code, but it doesn't move the view down.
I'm assuming autolayout is moving it back into position, so I tried adding this code into viewWillLayoutSubviews and viewDidLayoutSubviews. But when I do this the navigationbar doesn't move down until the first time the tableview is scrolled.
What do I need to do to force the navigationBar to move down (and stay down) before the screen appears?
Are you using storyboards? Set the Y in storyboards to 20, Make your viewcontroller implement UINavigation bar, then add this code:
-(UIBarPosition)positionForBar:(id<UIBarPositioning>)bar{
return UIBarPositionTopAttached;
}
This will tell the app that the navigation bar is to be attached, it will remain at 20px but extend the background all the way up.. So essentially it'll look like it's at y = 20.
I have a UINavigationController with standard UINavigationBar. When presenting certain UIViewControllers and orientations, the UINavigationBar may or may not appear and it may or may not have a prompt element. This means that the bar height changes frequently.
I have some subviews below the UINavigationBar set with NSLayoutConstraints to topLayoutGuide. It generally lays out as expected, adjusting vertical position of the subviews appropriately based on the height of the UINavigationBar. What it does not do is move the subviews at times when the UINavigationBar is animated after the view is already displayed.
Specifically, coming from a state with UINavigationBar hidden, transition to a UIViewController which does not hide the navigation bar to one which does. The view displays, then navigation bar animates into place. The subviews do not move down. If I rotate the device, every things lays out appropriately again. Only when animating the navigation bar in and out or to display/hide the prompt I not find a hook to reevaluate the constraints.
I tried [self.view updateConstraints] and [self.view updateConstraintsIfNeeded] in various places such as viewDidAppear, viewDidLayoutSubviews. Nothing seems to update that topLayoutConstraint.
I am familiar with edge restraints, translucent navigation bar and other various methods of keeping the entire view from appearing under the navigation bar. I do want to keep view full size and I want the translucent bar so these are not solutions for me. It seems the constraints should handle this automatically, hence the "auto" in auto layout.
To simplify, for recreation, UINavigationController with rootViewcontroller showing normal navigation bar with just a title. In viewDidLoad of the next presented viewController I have [self.navigationContoller setPrompt:self.myPrompt]. The view is presented, when the prompt is set, the navigation bar grows larger. Some labels below the bar are set with relation to topLayoutGuide, which places them correctly initially. I expect they would move down when the bar grows. Rotate device back and forth, they now layout correctly. Pop the viewController and push back to top, repeats as above.
So, it turns out it was all me. After trying all manner of forcing layout updates in all sorts of ways, the solution was to move the [myView setPrompt:myPrompt] out of viewDidLoad and call it in viewDidAppear instead.
Works completely as expected. Navbar grows, subviews shift and shrink as needed. Now I have to hunt down all the experimental code I plastered everywhere trying to do it wrong.