I have a modal view that I'm presenting over the current view that has a UINavigationBar as a subview. Everything's working great, except that the UINavigationBar doesn't want to behave according to the autolayout constraints. Everything else in the view behaves as desired.
For some reason, the left and right bar button items are cut off on the edges of the view. I inspected the view at runtime to reveal that the total width of the UINavigationBar is the right width, but the bar buttons aren't conforming.
I also checked to make sure I didn't have negative margins or some other anomaly in the constraint definitions.
I have also tried setting the frame of the UINavigationBar manually, but it yielded no improvement.
Problematic View
Constraints
I'd like to keep the UINavigationBar, because it gets styled globally with the rest of my app (as opposed to creating a custom UIView imitation and styling it individually). Does anyone know what handle to jiggle to get the bar button items to conform to the right width?
Related
I'm trying to get this to work on iOS 7 and 8+.
In loadView of the viewController, I add a UISegmentedControl, along with flexible spaces, as items to a UIToolBar. I then add the UIToolbar as a subview to the main view, setting the vertical position to be the height of the navigation bar.
First problem. The UISegmentedControl is vertically off center so the top of it, is cut off.
Second problem. Rotating to landscape messes it all up. Specifcally, the UIToolbar seems to move underneath the navigation bar whereas the UISegmentedControl doesn't.
Autoresizing issue? I've tried various settings and can't seem to get it to center vertically within the UIToolbar.
It could be that your UIToolbar constraints are not set properly and also that there is no flexible space around the segmented control. Here's a link to a storyboard file I made that have proper constraints and flexible space, tested to work.
Preview:
Here's the Storyboard file: http://www.filedropper.com/main_4
I need to do exactly what the photos app is doing when you press the select button. Basically just hides the UITabBar and presents a UIToolbar. For some reason this seems to be incredibly difficult if you don't want to implement a complete hack. I found a hack if you shrink the height of the UITabBar and change it's alpha to 0 but when you set it's height back to the default the image and text is condensed.
Turns out that I ended up just needing to call [self.tabBarController.tabBar setHidden:YES] to hide the tabBar and instead of using my existing UINavigationController's toolbar I create my own instance of a UIToolbar and add it as a subview of my view controller. Then using autolayout I pinned it to the leading, trailing, and bottom edge of the view. This handles rotation and other issues.
My app has a view controller that due to the fact it plays its own custom transition animations, provides its own standalone UINavigationBar view at the top (As opposed to using a UINavigationController).
When using an iPhone, and when rotating the device, I would like the UINavigationBar to automatically apply the landscape UIBarMetrics properties (eg, change height, change the background image, resize the buttons etc), but by default, it does not. This is a problem on iOS 7, since even if I manually change the height of the UINavigationBar, the UIBarButtonItem elements don't change their vertical positions.
Is there a way to manually 'tell' the UINavigationBar to apply specific bar metric properties to itself? Or is that actually an implementation inside UINavigationController, and not UINavigationBar?
After various testing and trial and error after asking this question, I eventually worked out a solution that fixed all of my issues, so I'll post it here under the solution I'd previously accepted.
When my app is displayed in landscape on an iPhone, I wanted the UINavigationBar at the top to shrink to the standardly accepted 32 points high, as is the case with any apps that use the UINavigationController class. However, as I am not using a UINavigationController for this particular view (for varying reasons of feasibility), I needed to implement this manually.
To account for the new transparent status bar in iOS 7, I adjusted the origin and size of the UINavigationBar so it encompassed both the bounds of the status bar, and the normal UINavigationBar region (ie, so the UINavigationBar frame origin was {0,0}, and the height was 52 points.)
Unfortunately, this happened:
While the bar itself is rendering at the proper position and height, all of the content in the bar, including the title and buttons are not positioned properly, being much too high, almost touching the status bar content.
It was pretty obvious what was happening. The navigation bar content is being vertically aligned to its own middle, completely disregarding the presence of the status bar content.
When I tested the same orientations with a normal UINavigationController, this was not the case, and the title and buttons in the UINavigationBar from the UINavigationController worked absolutely fine. Apple had done SOMETHING in there that wasn't part of the normal UINavigationBar implementation.
Going on this, I picked apart the view layout hierarchy of a UINavigationControllerto see what was happening to the UINavigationBar in there (Mainly calling a lot of NSLog() statements that would dump the subviews of the navigation bar.)
This is what I discovered:
From the looks of it, Apple have employed a relatively sneaky hack to achieve this effect. It turns out the actual UINavigationBar is actually placed right below the status bar (ie at point {0,20}) and only has a height of 32 points. Then, what happens is a private subview inside the UINavigationBar in charge of rendering the background is extended upwards, outside of the bounds of the navigation bar to encompass the region behind the status bar (ie, its origin is {0, -20}, and its height is 52 points, local to the navigation bar's subview coordinate space).
So by doing that, not only does the content vertically align properly, but the translucent effect still extends behind the status bar.
Anyway, after I discovered this, it was pretty straightforward to write a solution. All I needed to do was reposition and resize the UINavigationBar back to how I had it iOS 6 (ie, 20 points down, and only 32 points high), and then implement a UINavigationBar subclass that override the layoutSubviews method, grabbed the internal background view (Doing a quick subview check for a view with a class name that matched "Background"), and then manually extended it.
The bar metrics properties you can set on a UINavigation bar are things like background image and the title vertical position. Heigh and width need to be set from within your view controller.
If you need to manually tell the navigation bar to change it's size when the orientation changes you can implement the method - (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration1 in your view controller and change the size there.
Another option you can use is to use autolayout to specify that the width of your navigation bar is pinned to the left and right sides of its superview and let it figure out how wide it should be. For example
UINavigationBar *bar = [[UINavigationBar alloc] init];
bar.translatesAutoresizingMaskIntoConstraints = NO;
[self.view addSubview:bar];
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:#"H:|[bar]|"
options:0
metrics:nil
views:NSDictionaryOfVariableBindings(bar)]];
[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:#"V:|[bar(44)]|"
options:0
metrics:nil
views:NSDictionaryOfVariableBindings(bar)]];
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.
in my app I have a simple UITableViewController that's just plain Objective-C code, no .xib or storyboard involved. It represents the contents of one tab in a tab bar.
Since iOS 7 its contents are overlapped by the status bar at the top and tab bar at the bottom.
Using only code, how can I make the table view add space at the top and bottom to align with topLayoutGuide and bottomLayoutGuide?
I know about
self.edgesForExtendedLayout=UIRectEdgeNone;
but that seems to simply shrink the table view to not intersect the tab bar and to disable the transparency of the tab bar. Instead I'd like the table view to add some padding.
Thanks!
Update:
I've also tried explicitly setting automaticallyAdjustsScrollViewInsets to YES, but that didn't help either (should be the default behavior anyway).
It seems this is not (yet) supported, at least for programmatically created UITableViewControllers without an UINavigationController that's embedding them.
I checked the position for both layout guides, and at run-time both off-sets read 0 distance from the edges of the screen. Hence automaticallyAdjustsScrollViewInsets won't set the insets correctly.
So now I actually modify my first section header and last section footer manually to add 21 pixels at the top and 50 pixels at the bottom respectively.
Bummer. :-(