In storyboard, in a view controller I tried add a navigation bar under the status bar, running it, it is transparent and shows a label that's supposed to be blurred, like by navigation bar.
But when placing the same view controller embedded in a navigation view controller, the underneath background image could be blurred, which is my intention.
What are these two way different results? What need to do for the firs method to make status bar blur?
Thanks!
In iOS 7 the status bar is transparent by default. The blurring you're seeing when there's also a navigation bar is actually created by the navigation bar. So to create the effect you're looking for without a navigation bar, you need to position a view that produces a blurring effect beneath the status bar.
For reference, add your view with a frame provided by:
CGRect statusBarFrame = [[UIApplication sharedApplication] statusBarFrame];
I know this is old, just for reference, I solved this by setting self.navigationController.navigationBar.clipToBounds = NO
I haven't tested this completely, but go to your plist file and check the following settings:
"View controller-based status bar appearance": If this is set to "Yes", then it should display a status bar that is unique to each View Controller, which might be what you need.
"Status bar style": You may set this to three different styles: Opaque black, Gray, and Transparent black.
Let me know if this worked for you.
UINavigationController will alter the height of its UINavigationBar to either 44 points or 64 points, depending on a rather strange and undocumented set of constraints. If the UINavigationController detects that the top of its view’s frame is visually contiguous with its UIWindow’s top, then it draws its navigation bar with a height of 64 points. If its view’s top is not contiguous with the UIWindow’s top (even if off by only one point), then it draws its navigation bar in the “traditional” way with a height of 44 points. This logic is performed by UINavigationController even if it is several children down inside the view controller hierarchy of your application. There is no way to prevent this behavior.
It looks like you are positioning your view hierarchy in the first example starting at the point (0,20). Also, is that a UIToolbar or a UINavigationBar? If it's the latter, why are you using it by itself and not using it inside of UINavigationController?
If you do not use UINavigationController and are instead using custom view controller containers, you'll need to position your views accordingly.
See this answer for a thorough explanation.
I have similar UI design and based on Matt Hall answer and some article I've googled, I come up with something like this:
- (void)viewDidLoad {
[super viewDidLoad];
if (NSFoundationVersionNumber>NSFoundationVersionNumber_iOS_6_1) {
CGRect statusBarFrame = [self.view convertRect: [UIApplication sharedApplication].statusBarFrame fromView: nil];
UIToolbar *statusBarBackground = [[UIToolbar alloc] initWithFrame: statusBarFrame];
statusBarBackground.barStyle = self.navBar.barStyle;
statusBarBackground.translucent = self.navBar.translucent;
statusBarBackground.autoresizingMask = UIViewAutoresizingFlexibleBottomMargin | UIViewAutoresizingFlexibleWidth;
[self.view addSubview: statusBarBackground];
}
}
Where self.navBar points to navigation bar added in storyboard. This is needed only in case when it runs on iOS7 that is why I've added this condition (my app has to support iOS5).
This works like a charm.
alternative approach (enforce status bar size) is also good:
- (void)viewDidLoad {
[super viewDidLoad];
if (NSFoundationVersionNumber>NSFoundationVersionNumber_iOS_6_1) {
CGRect statusBarFrame = [self.view convertRect: [UIApplication sharedApplication].statusBarFrame fromView: nil];
self.navBar.frame = CGRectUnion(statusBarFrame, self.navBar.frame);
}
}
I've found another solution I think this is best since it involve only storyboard and no code is required.
Switch storyboard view to 6.1 mode (view as: iOS 6.1 and Earlier)
Select problematic UINavigationBar
in size section add 20 delta height in "iOS6/7 Deltas"
Switch back view to 7.0 mode (view as: iOS 7.0 and Later), and be happy with result.
when you embed view controller with navigation view controller that time you will see navigation bar to all the view controller you are pushing to from same view controller. In your first case you are adding the navigation bar object, insted of that you can select view controller from storyboard , go to attributes inspector tab & from their select Top bar as translucent navigation bar.
Related
I know this question has been asked several times and the solutions I have seen have been very helpful. But since i have 2 conflicting requirements, I am a little stranded and hoping to find some help.
So here are the requirements:
We have multiple View controllers out of which only one needs to be full screen (without status bar on the top).
The other view controllers need to show a black status bar with a dark gray navigation bar
The First View controller is embedded in a navigation controller.
As recommended in some of the other posts, I did the following
Set UIViewControllerBasedStatusBarAppearance to NO
Added this code in app delegate
CGRect frame = [[UIScreen mainScreen] bounds];
self.window.frame = CGRectMake(0,20,frame.size.width, frame.size.height-20);
self.window.bounds = self.window.frame;
It works fine if I only stay in those View controllers that have the status bar.
The moment I open the FULL screen view controller, that VC is cut off on the top as shown here.
Additionally when I come back to the Main view controller, now thats shifted up as well and the title bar is where the status bar was showing.
I have tried to push the views back down by resetting the view.frame and requesting layout but it doesnt take effect.
Any suggestions on how to resolve this?
Don't change self.window.bounds in app delegate. Instead, in your view controllers try something like this:
-(void)viewWillAppear:(BOOL)animated
{
[self.navigationController setNavigationBarHidden:YES/NO animated:YES];
[self setNeedsStatusBarAppearanceUpdate]; // For showing/hiding status bar
[super viewWillAppear:animated];
}
- (BOOL)prefersStatusBarHidden {
return YES/NO;
}
You will have different frames for the view in ViewDidLoad according to whether status bar and navigation bar are there.
I started building a TableView in my app by using a TableViewController in a storyboard. When you do this, you have a very cool effect when you scroll down your list : the cells moving behind the nav bar get blurred.
Some time later, I had to move from this TableViewController to a ViewController with a TableView inside (I had to add other views at the bottom of the table).
In order to avoid having the first cells hidden by the navigation bar (being over it), I added constraints to the Top and Bottom Layout Guides, and to the left and right edges of the view.
This works fine, but I lost the cool blurred scrolling effect : the cells seem to be disappearing before going behind the navigation bar.
I've seen workarounds with people not using constraints and putting magic numbers in interface builder. I cannot do this, first because I dislike it, and second because I have to be iOS 6 compatible.
What did I miss to be able to benefit again from the blurred navigation bar effect ?
You have to manually adjust the contentInset of the table view and make sure the table view frame origin is 0, 0.
In this way the table view will be below the navigation bar, but there will be some margin between the content and the scroll view edges (the content gets shifted down).
I advise you to use the topLayoutGuide property of the view controller to set the right contentInsets, instead of hard coding 64 (status bar + navigation bar).
There's also bottomLayoutGuide, which you should use in case of UITapBars.
Here is some sample code (viewDidLoad should be fine):
// Set edge insets
CGFloat topLayoutGuide = self.topLayoutGuide.length;
tableView.contentInset = UIEdgeInsetsMake(topLayoutGuide, 0, 0, 0);
By the way, this properties of UIViewController might help you (you should not need to change their default values, but I don't know what your view hierarchy is):
automaticallyAdjustsScrollViewInsets
edgesForExtendedLayout
extendedLayoutIncludesOpaqueBars
The tableView needs to be full screen. That is underneath the top and bottom bars. Note don't use the top and bottom layout guides as they are used for positioning relative to the bars not underneath.
Then you need to manually set the content inset of the tableview. This sets the initial scroll position to under the top bar.
Something like:
CGSize statusBarSize = [[UIApplication sharedApplication] statusBarFrame].size;
CGFloat h=MIN(statusBarSize.width, statusBarSize.height);
UIEdgeInsets e = UIEdgeInsetsMake(self.navigationController.navigationBar.bounds.size.height + h,
0.0f,
0.0f,
0.0f);
self.tableView.contentInset = e;
Not you get this functionality for free when using a tableView controller and the "Automatically Adjust content inset" settings
You probably have the coordinates of your tableView not set to (0, 0) to map to those of the viewController.view.frame or viewController.view.bounds. If you have done that, try setting
self.navigationController.navigationBar.translucent = YES;
UIViewController property edgesForExtendedLayout does the trick. If you are using storyboards just make sure Extended Edges Under Top Bars is on (and it is by default).
If you are creating your view controller programmatically try this:
- (void)viewDidLoad
{
[super viewDidLoad];
self.edgesForExtendedLayout = UIRectEdgeAll;
}
And of course, your table view needs to have proper autoresizing mask/layout constraints
edgesForExtendedLayout is not what you want here, as this will limit the table view underneath the navigation bar. In iOS 7, the view controllers uses fullscreen by default, and the property controlling where the tableview content starts is automaticallyAdjustsScrollViewInsets. This should be YES by default, so check if it is somehow set to NO, or try setting it explicitly.
Check this answer for a good explanation on how this works:
https://stackoverflow.com/a/19585104/1485715
I have a view controller in my app that has a navigation bar dragged on it in the storyboard. It was working fine in the iOS 6 but in iOS 7 it look like this:
The status bar and the navigation bar should no collide with each other. I have seen a lot of such questions on the stack overflow but they didn't of much help to me.
Some questions say that i should use this "self.edgesForExtendedLayout = UIRectEdgeNone;" but it didn't work. Some say i should remove the navigation bar and embed it inside the navigation controller that i cannot do due to the way my program is implemented. Some solutions suggests to use the view bounds and all but it didn't work for me as well.
What is the one thing that can help me resolve this issue. Thanks in advance!
UPDATE: I have embedded the view controller inside a uinavigation controller. Removed the navigation bar that was earlier manually added in it. Now it looks ok in the storyboard but when i run it, it shows the following:
It is showing text from another view controller that is currently behind it that is its parent view controller. Means its transparent now. Can anyone point out what i am doing wrong?
The latest version of the iOS has brought many visual changes and from a developer's point of view, the navigation and status bar are two noticeable changes.
The status bar is now transparent and navigation bar behind it shows through. The navigation bar image can even be extended behind the status bar.
First of all, if you are a beginner and have just started iOS development and are confused the way status bar and navigation bar is working, you can simply go through a blog post HERE that i found very useful. It has all the information related to navigation and status bar in iOS 7.
Now coming to the answer of your question. First of all i can see two different problems. One is that your status bar and navigation bar are both kind of colliding with each other as shown by you in the question with an image.
PROBLEM: Well the problem is that your have earlier dragged a navigation bar in your view controller which was working in iOS 6 correctly but with the arrival of iOS 7 SDK, this approach is resulting in status bar and navigation bar overlapping with each other.
SOLUTION to First Problem: You can either use UIBarPositionTopAttached or you can use view bounds and frames, i can also suggest and link you to Apple's documentation and bla bla bla but that would take some time for you to solve the issue.
The best and the most easiest way to solve this issue is to just embed your view controller inside a navigation controller and thats it. You can do it by just selecting the view controller and going to Editor > Embed In > Navigation Controller. (If there is any content on your old navigation bar, you can first drag it down, embed the view controller in navigation controller and then move the bar buttons on the new navigation bar and then delete the old navigation bar)
SOLUTION to Second Problem: This solution is for your specific question that you have mentioned in the update and is not for the general public reading this. As you can see that navigation and status bar is not visible and a transparent area is showing the parent view controller. I am not really use why you are facing this issue but most probably because of some third party library like ECSlidingView or any other is involved. You can select this view controller in your storyboard and set the background color of the view to be the same as your navigation bar. This will stop showing the parent view controller behind and your navigation bar and status bar will start showing. Now you can cover the rest of your view controller with text view or what ever your are using in it.
Hope this helps!
The navigation bar is too close to the status bar because starting in iOS 7, the status bar is more of an overlay over the whole view controller's view. Since your navigation bar is at (0, 0), the status bar will show on top of the navigation bar. To solve this, simply move the navigation bar down (or, as others have said), create a constraint between the navigation bar and the topLayoutGuide.
When you do that, you will see that there is now a 20 point gap between the navigation bar and the top of the screen. That's because you just moved the navigation bar down 20 points. "But UINavigationController can do it right!" Absolutely, and it does so by implementing UIBarPositioningDelegate on your view controller. This is a one-method protocol that should be implemented like this:
- (UIBarPosition)positionForBar:(id<UIBarPositioning>)bar {
return UIBarPositionTopAttached;
}
After adding your view controller as the delegate for the navigation bar, you'll notice the navigation bar is still shifted down 20 points, but its background will extend up underneath the status bar, just like in UINavigationController.
Another thing you're seeing is that the navigation bar is translucent, meaning anything underneath the navigation bar will be visible to some extent. The translucent property on UINavigationBar is set to YES by default on iOS 7. Before iOS 7, the default was NO.
you can simply do this:
1) add a constrain between the Navigation Bar and Top Layout Guide (select navigationBar, hold ctrl key and go to Bottom Layout Guide, unhold ctrl key)
2) select vertical spacing:
3) set constant to 0:
Result:
UPDATE
In your AppDelegate file you can add this:
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool
{
// Prevent Navigationbar to cover the view
UINavigationBar.appearance().translucent = false
}
I suggest you in your viewDidLoad method you try:
self.navigationController.navigationBar.translucent = NO;
(by default it is yes now)
https://developer.apple.com/library/ios/documentation/uikit/reference/UINavigationBar_Class/Reference/UINavigationBar.html#//apple_ref/occ/instp/UINavigationBar/translucent
This works for me i hope you also have same luck :).
Add below code in your view.
-(void) viewDidLayoutSubviews
{
CGRect tmpFram = self.navigationController.navigationBar.frame;
tmpFram.origin.y += 20;
self.navigationController.navigationBar.frame = tmpFram;
}
It basically change location of navigation bar.
This is new feature with IOS7. Instead of staring at 20 px navigation bar in IOS7 staring at 0 px. As a solution shift the whole view downwards to 20 px or you can use image for navigation bar with height 64px.
In case it still helps someone, this is what worked for me for moving the Navigation Bar little bit down in ios 7 and above:
-(void)viewWillLayoutSubviews
{
float iosVersion = 7.0;
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= iosVersion) {
// iOS 7+
CGRect viewFrame = self.view.frame;
viewFrame.origin.y += 10;
self.view.frame = viewFrame;
}
}
On a device with ios 6.1 and below the Navigation Bar will be unchanged, as it was before.
And this is what I used to make the contents of the Status Bar lighter:
-(UIStatusBarStyle)preferredStatusBarStyle{
return UIStatusBarStyleLightContent;
}
If your UIViewController is NOT in a UINavigationController and you're using UIStoryBoard, you can set the "iOS 6/7 Deltas" to 20 for the delta Y, for every subview that needs to be offset from the UIStatusBar.
Using Swift:
As #Scott Berrevoets said in his answer you need to implement the method positionForBar in the protocol UIBarPositioningDelegate, but as the UINavigationBarDelegate protocol implements this protocol :
public protocol UINavigationBarDelegate : UIBarPositioningDelegate {
...
}
You only need to set the delegate of the UINavigationBar you set using Storyboard and implement the method and it's done, like in this way:
class ViewController: UIViewController, UINavigationBarDelegate {
#IBOutlet weak var navigationBar: UINavigationBar!
override func viewDidLoad() {
super.viewDidLoad()
self.navigationBar.delegate = self
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func positionForBar(bar: UIBarPositioning) -> UIBarPosition {
return UIBarPosition.TopAttached
}
}
NOTE:
It's worth to mention if you set the position of the y-axis of the navigation bar, let's say to 40 from the top, then it will extend underneath to the top from this position, to simulate the behaviour of the UINavigationController you need to set to 20 from the top.
I hope it will help you.
First, set UIViewControllerBasedStatusBarAppearance to NO in Info.plist.
Then, in AppDelegate's application:didFinishLaunchingWithOptions: method add:
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7) {
[application setStatusBarStyle:UIStatusBarStyleLightContent];
self.window.clipsToBounds = YES;
self.window.frame = CGRectMake(0, 20, self.window.frame.size.width, self.window.frame.size.height-20);
self.window.bounds = CGRectMake(0, 20, self.window.frame.size.width, self.window.frame.size.height);
}
return YES;
In iOS 7 app occupies 100 % of screen size.This not a problem .
http://www.doubleencore.com/2013/09/developers-guide-to-the-ios-7-status-bar/
in earlier iOS window start after statusbar and in iOS 7 window starts from 0px in earlier version view height is 460 (iPhone 4s and earlier) and 548 (iPhone 5) but in iOS 7 view height is 480 (iPhone 4s and earlier) and 568 (iPhone 5 and later) so you have to start view arrangement after 2o px or you have to start view from 20px.
you can write below code in rootviewcontroller or in all viewcontroller for set view from 20px
#define IOS7_HEIGHT 64
- (void)viewDidLayoutSubviews {
NSString *currSysVer = [[UIDevice currentDevice] systemVersion];
if ([currSysVer compare:#"7.0" options:NSNumericSearch] != NSOrderedAscending)
{
CGRect frame=[self.view frame];
if (frame.origin.y!=IOS7_HEIGHT) {
frame.origin.y = IOS7_HEIGHT;
frame.size.height -= IOS7_HEIGHT;
[self.view setFrame:frame];
[self.view layoutSubviews];
}
}
}
here height is 64 because 20 for statusbar and 44 for navigationbar.
try below code it will help you. and your problem will be solved.
For the ones who are having problems implementing #Masterfego 's solution (which is also the official, but I have had problems with Xcode 6.3 and automatic constraints), this is what I did:
I have a UIViewController with an added Navigation Bar. I selected the NAvigation bar and added a height constraint of 64px. We later see a warning that the navbar will be higher (but this is what we do). Finally, you can see that the Status bar looks nice and has the same color as the navbar. :)
PS: I can't post images yet.
You can probably create constraints that are attached to the top layout guide to specify the navigation bar's position relative to the status bar. See the iOS 7 UI Transition Guide: Appearance and Behavior section for more information about using the layout guides.
it's the best answer.
But I wanted know how to use a Storyboard and dragged UINavigationBar on it.
When I implemented the delegate method, and set the return result to UIBarPositionTopAttached, it did not work.
- (void)viewDidLoad{
self.navigationbar.delegate = self;
}
- (UIBarPosition)positionForBar:(id<UIBarPositioning>)bar{
NSLog(#"Got it");
//
// CGRect frame = self.navigaitonBar.frame;
//
// frame = CGRectMake(0, 20, CGRectGetWidth(frame), CGRectGetHeight(frame));
// self.navigaitonBar.frame = frame;
//
// NSLog(#"frame %f",frame.origin.y);
return UIBarPositionTopAttached;
}
If you use Xcode 6 and Swift, you can make it:
Open to info.plist file of your app.
Add a ViewControllerBasedStatusBarAppearance Boolean key if it is not existing and assign value “NO”.
Add “Status bar style” key if it is not existing and select “Opaque black style” value to it.
I was facing issue when full screen ModalViewController was opening from my MainViewController, NavigationBar position was getting changed when user was coming back to MainViewController from ModalViewController.
Issue which I noticed is status bar height was not getting included when user came back to MainViewController. Please debug and check origin of your NavigationBar before and after coming back to your ViewController.
// This method will adjust navigation bar and view content.
private func adjustNavigationControllerIfNeeded() {
var frame = self.view.frame
let navigationBarHeight = self.navigationController!.navigationBar.frame.size.height
if(frame.origin.y == navigationBarHeight && !UIApplication.shared.isStatusBarHidden) {
// If status bar height is not included but it is showing then we have to adjust
our Navigation controller properly
print("Adjusting navigation controller")
let statusBarHeight = UIApplication.shared.statusBarFrame.height
frame.origin.y += statusBarHeight // Start view below navigation bar
frame.size.height -= statusBarHeight
self.view.frame = frame
self.navigationController!.navigationBar.frame.origin.y = statusBarHeight // Move navigation bar
}
}
And call it from viewWillAppear method -
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
self.adjustNavigationControllerIfNeeded()
}
I have a problem when dragging a navigation bar or toolbar (storyboard) to my view controller.
UINavigationBar:
As you can see in the image above, the right button is almost overlapping the status bar.
With a UIToolbar it happens the same:
This view controllers are intended to be used as a Modal, that's the reason I'm not using a UINavigationController.
In another section I use a UINavigationController and it appears as I expect:
How can I drag a UINavigationBar / UIToolbar to a view controller without overlapping the status bar?
The navigation bars or toolbars have to be at (0, viewController.topLayoutGuide.length) with bar positioning of UIBarPositionTopAttached. You should set the delegate of your navigation bar or your toolbar to your view controller, and return UIBarPositionTopAttached. If positioned correctly, you will have the result in your third image.
More information here:
https://developer.apple.com/documentation/uikit/uibarpositioningdelegate?language=objc
Do these steps
Drag the NavigationBar to your ViewController in Xib, set the ViewController as its delegate.
Note that the NavigationBar should be at (0, 20)
In ViewController, conform to the UINavigationBarDelegate
#interface ETPViewController () <UINavigationBarDelegate>
Implement this method
- (UIBarPosition)positionForBar:(id <UIBarPositioning>)bar
{
return UIBarPositionTopAttached;
}
positionForBar tells the NavigationBar if it should extend its background upward the Status Bar
Please see my answer here, I've copied the content below for convenience:
https://stackoverflow.com/a/18912291/1162959
The easiest workaround I've found is to wrap the view controller you want to present inside a navigation controller, and then present that navigation controller.
MyViewController *vc = [MyViewController new];
UINavigationController *nav = [[UINavigationController alloc]
initWithRootViewController:vc];
[self presentViewController:nav animated:YES completion:NULL];
Advantages:
No mucking with frames needed.
Same code works on iOS 6 an iOS 7.
Less ugly than the other workarounds.
Disadvantages:
You'll probably want to leave your XIB empty of navigation bars or toolbars, and programatically add UIBarButtonItems to the navigation bar. Fortunately this is pretty easy.
You can resolve this issue by using Auto Layout, as per this techincal note (Preventing the Status Bar from Covering Your Views).
Here are some excerpts:
Add the Vertical Space Constraint to the top-most view
Control drag from the UIToolbar to the "Top Layout Guide"
In the popover, choose "Vertical Spacing"
Change the "Vertical Space Constraint" Constant to 0 (zero)
If you have other subviews below the UIToolbar, anchor those views to
the toolbar instead of the Top Layout Guide
This will support ios6 and ios7.
You can also manage it by increasing height of navigation bar by providing image of size 620x128 for ios version. And this image is used in :
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0)?YES:NO) {
[self.navigationController.navigationBar setBackgroundImage:[UIImage imageNamed:#"newImage.png"] forBarMetrics:UIBarMetricsDefault];
}else{
[self.navigationController.navigationBar setBackgroundImage:[UIImage imageNamed:#"previousImage.png"] forBarMetrics:UIBarMetricsDefault];
}
I gave up and had to set the navbar height constraint to 64 in x xib based VC cause viewController.topLayoutGuide.length is 0 in viewDidLoad despite statusbar being present :-[
which means in a non universal app on ipad you'd have 20 px on the top of the
view wasted (cause status bar is separate from the iphone simulation window)
I have been reading a lot about iOS7 UI transition.
I am not able to get what these three properties automaticallyAdjustsScrollViewInsets, extendedLayoutIncludesOpaqueBars, edgesForExtendedLayout??
For example I am trying to make my view controllers start below the status bar but I am not able to achieve it.
Starting in iOS7, the view controllers use full-screen layout by default. At the same time, you have more control over how it lays out its views, and that's done with those properties:
edgesForExtendedLayout
Basically, with this property you set which sides of your view can be extended to cover the whole screen. Imagine that you push a UIViewController into a UINavigationController. When the view of that view controller is laid out, it will start where the navigation bar ends, but this property will set which sides of the view (top, left, bottom, right) can be extended to fill the whole screen.
Let see it with an example:
UIViewController *viewController = [[UIViewController alloc] init];
viewController.view.backgroundColor = [UIColor redColor];
UINavigationController *mainNavigationController = [[UINavigationController alloc] initWithRootViewController:viewController];
Here you are not setting the value of edgesForExtendedLayout, therefore the default value is taken (UIRectEdgeAll), so the view extends its layout to fill the whole screen.
This is the result:
As you can see, the red background extends behind the navigation bar and the status bar.
Now, you are going to set that value to UIRectEdgeNone, so you are telling the view controller to not extend the view to cover the screen:
UIViewController *viewController = [[UIViewController alloc] init];
viewController.view.backgroundColor = [UIColor redColor];
viewController.edgesForExtendedLayout = UIRectEdgeNone;
UINavigationController *mainNavigationController = [[UINavigationController alloc] initWithRootViewController:viewController];
And the result:
automaticallyAdjustsScrollViewInsets
This property is used when your view is a UIScrollView or similar, like a UITableView. You want your table to start where the navigation bar ends, because you wont see the whole content if not, but at the same time you want your table to cover the whole screen when scrolling. In that case, setting edgesForExtendedLayout to None won't work because your table will start scrolling where the navigation bar ends and it wont go behind it.
Here is where this property comes in handy, if you let the view controller automatically adjust the insets (setting this property to YES, also the default value) it will add insets to the top of the table, so the table will start where the navigation bar ends, but the scroll will cover the whole screen.
This is when is set to NO:
And YES (by default):
In both cases, the table scrolls behind the navigation bar, but in the second case (YES), it will start from below the navigation bar.
extendedLayoutIncludesOpaqueBars
This value is just an addition to the previous ones. By default, this parameter is set to NO. If the status bar is opaque, the views won't be extended to include the status bar, even if you extend your view to cover it (edgesForExtendedLayout to UIRectEdgeAll).
If you set the value to YES, this will allow the view to go underneath the status bar again.
If something is not clear, write a comment and I'll answer it.
How does iOS know what UIScrollView to use?
iOS grabs the first subview in your ViewController's view, the one at index 0, and if it's a subclass of UIScrollView then applies the explained properties to it.
Of course, this means that UITableViewController works by default (since the UITableView is the first view).
Not sure if you are using storyboards, but if you are, to make your view controllers start below the status bar (and above the bottom bar):
Select the view controller in IB,
In the attributes inspector, deselect 'Extend Edges - Under Top Bars' and 'Extend Edges - Under Bottom Bars'.
I am using storyboards and using the above advice worked however I wasn't exactly sure how to implement it. Below is a short example in swift of how it cleared up the problem by putting the recommended solution into the ViewController.
import Foundation
import UIKit
// This ViewController is connected to a view on a storyboard that
// has a scrolling sub view.
class TheViewController: UIViewController {
// Prepares the view prior to loading. Putting it in viewDidAppear didn't work.
override func viewWillAppear(animated: Bool) {
// this method is an extension of the UIViewController
// so using self works as you might expect.
self.automaticallyAdjustsScrollViewInsets = false
// Default is "true" so this sets it to false tells it to use
// the storyboard as you have it placed
// and not how it thinks it should place it.
}
}
My Problem:
Auto Adjust set to true by default causing a difference between storyboard design and simulator
Resolved:
Code above applied, turning off the auto-adjust.
I solved this problem by adding this line, but my problem was related to a UIView, not UIScrollView
self.navigationController.navigationBar.translucent = NO;
Just bare in mind that
automaticallyAdjustsScrollViewInsets
property works only if some kind of scroll view (table view, collection view,...) is either
The view of VC, or
First subview of this view
Other suggested, that it doest work even if it is the first subview, but there are other scroll views in the view hierarchy.
EDIT (extension DIY)
If you want similar behaviour even if you can't fulfil these conditions (e.g. you have a background image below the scroll view), you can adjust the scroll view insets manually. But please don't set it to constant like 44 or 64 or even 20 like many suggest around SO. You can't know the size ever. There can be the incall/gps/audio notification, navigation bar doesn't have to be always 44 pts etc.
I think the best solution is to use layoutGuide length in didLayoutSubviews:
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
scrollView.contentInset = UIEdgeInsets(top: topLayoutGuide.length, left: 0, bottom: 0, right: 0)
scrollView.scrollIndicatorInsets = scrollView.contentInset
}
You can use the bottomLayoutGuide in the same way.