I'm a bit confused by the proper frame sizing of a table view to fit within my screen.
Here's my setup of view controllers within view controllers:
UITabBarController
UINavigationController as one of the tab bar viewcontrollers; title bar hidden
ViewController - a container view controller because I need the option to place some controls beneath the UITableView, sometimes (but not in the current scenario)
UITableViewController
Now, my question is what the proper frame dimensions of the UITableview should be. Here's what I've got in the ViewController viewDidLoad method. I used subtracted 49.0 (the size of the tab bar) from 480.0. However, this leaves a black bar at the bottom. 20.0 appears to do it (coincidentally?) the size of the status bar, but I don't understand why that would be. Wouldn't the true pixel dimensions of the tableview be 480-49?
// MessageTableViewController is my subclass of UITableViewController
MessagesTableViewController *vcMessagesTable = [[MessagesTableViewController alloc] init];
CGRect tableViewFrame = CGRectMake(0, 0, 320.0, 480.0 - 49.0);
[[vcMessagesTable view] setFrame:tableViewFrame];
self.tableViewController = vcMessagesTable;
[self addChildViewController:vcMessagesTable];
[[self view] addSubview:vcMessagesTable.view];
Here's how it looks:
I've run into this problem also -- I think it would be best not to hard code the size but to refer to the size of one its ancestor controllers. In this case, the UINavigationController, that's the direct child of the tabBar controller should have the right frame to fill the whole screen minus the tabBar. So I would subtract (if you need to) from that frame height if you want space at the bottom, otherwise, just use that frame. I think that self.navigationController finds the nearest nav controller above your controller of interest.
Related
I am confused by the frame of self.view within a ViewController I have made the root ViewController of a UINavigationViewController. Lets say I add a red square UIView to self.view (where self.view is the embedded ViewController's view property). This red view is mostly occluded by the navigation bar. In other words, why doesn't self.view's frame's origin.Y = HeightOfNav bar? Instead it is 0.
I have read documentation that states a view added to the navigation controller resizes to take the nav bar's height into account, however, all my testing has shown this isn't the case. Not at any point in the view lifecycle does my view correct its origin to be visible. Perhaps I am setting up this viewcontroller/navigationController incorrectly such that the appropriate view-resizing does not take place but you can read the subsequent code to see if that is the case.
Here is the simple code where I generate these view controllers in appdelegate:
UIViewController * a = [[ViewController alloc] init];
UINavigationController * nav = [[UINavigationController alloc] initWithRootViewController:a];
self.window.rootViewController = nav;
Logging out self.view's frame in a's viewDidLoad, viewWillAppear, viewDidAppear, etc.. shows { 0, 0, screenWidth, screenHeight } (where screen* is the current simulator). So, 0,0 is behind a navBar and this is not the behavior I would expect.
Again, my expectation was that self.view would now have a frame whose origin starts after the NavigationBar at the top of any view inside a UINavigationController.
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 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.
This is a weird error that may just be an issue in Xcode for all I know. I have a tab bar controller where the first view is a UITableView with (obviously) a number of cells. When you select a cell, I've set up a segue on the MainStoryboard to go to a detail view controller. I want the tab bar to be hidden when I go to the detail view, so I went into the storyboard, chose my detail view, and clicked "Hides Bottom Bar on Push" in the editor screen that starts with "Simulated Metrics."
Everything works just fine, except that when I tap on a cell, a black bar flashes at the top of the UITableView screen, dropping the tableview cells down (as if the cells are falling down below the tab bar at the bottom), just before the screen pushes over to the detail view. The effect isn't harmful at all, but it's very disconcerting, and I'd like to smooth that out.
The only fix I've found is to uncheck the "Hides Bottom Bar when Pushed" option on the storyboard. That indeed does get rid of that black bar flash, but of course the tab bar stays on the screen when I go to the detail view, which is what I don't want.
Any ideas?
Just for completeness' sake, I went ahead and ran
[self.navigationController setToolbarHidden:YES animated: YES];
on the detail view controller's viewWillAppear method (and even tried it with the storyboard option both on and off), but there was no difference. The toolbar did indeed hide just fine, but I still got that black line at the top. So weird.
I know it is too late !!! I ran into same issue. It seems like the Auto resizing mask for the view was incorrect to be exact the UIViewAutoresizingFlexibleTopMargin. I checked this on in the xib file. If you are trying to do it in code make sure this flag -UIViewAutoresizingFlexibleTopMargin - is not included in the autoresizing mask.
Hope this will help some one in the future
I know it is a bit late, but I have same problem and I can't solve it with any of the previous answers. (I suppose this is the reason non was accepted).
The problem is that view size of the SecondViewController is same as view size of a previous ViewController, so too small to fit in a ViewController with Toolbar hidden. Thats why black background of a UITabBarController is visible at the top when transition is happening, and on a viewDidAppear view will stretch on right size.
For me it help to subclass root UITabBarController and set background color to same background color as SecondViewController has.
class RootViewController: UITabBarController {
override func viewDidLoad() {
super.viewDidLoad()
self.view.backgroundColor = Style.backgroundColor
}
}
Then you can leave checkbox checked inside storyboard and it will look ok.
P.S.
If you have some views, that is position on the bottom part of the view, you need to set bottom constraints so they are smaller by 49 (because this is the height of the toolbar), and then on viewDidAppear set the right constraint.
For example:
I have view that need to be position 44 px from bottom edge. Before, I have constraint set to 44 and I have some strange behaviour of that view. It was placed to height and then jump on the right place.
I fix this with setting constraint to -5 (44-49), and then in viewDidAppear set the constraint back to 44. Now I have normal behaviour of that view.
Wow I just had the same issue now, very painful, and no info on the net about it.
Anyway, a simple workaround for me was to change the current view's Frame moving the y coordinates up and making the height bigger by the height of the tab bar. This fixed the problem if done straight after pushing the new view onto the navigation controller. Also, there was no need to fix the Frame afterwards (it must be updated when the view is shown again).
MonoTouch code:
UIViewController viewControllerToPush = new MyViewController();
viewControllerToPush.HidesBottomBarWhenPushed = true; // I had this in the MyViewController's constructor, doesn't make any difference
this.NavigationController.PushViewController(viewControllerToPush, true);
float offset = this.TabBarController.TabBar.Frame.Height;
this.View.Frame = new System.Drawing.RectangleF(0, -offset, this.View.Frame.Width, this.View.Frame.Height + offset);
Objective C code (untested, just a translation of the monotouch code):
UIViewController *viewControllerToPush = [MyViewController new];
viewControllerToPush.hidesBottomBarWhenPushed = YES; viewControllerToPush.hidesBottomBarWhenPushed = YES;
float offset = self.tabBarController.tabBar.frame.size.height; float offset = self.tabBarController.tabBar.frame.size.height;
self.view.frame = CGRectMake(0, -offset, self.view.frame.width, self.view.frame.height + offset); self.view.frame = CGRectMake(0, -offset, self.view.frame.size.width, self.view.frame.size.height + offset);
Do this in viewWillAppear of detailViewController, it should work fine
subclass your navigation controller, or just find the navigation bar
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
let backdropEffectView = navigationBar.subviews[0].subviews[0].subviews[0] //_UIBackdropEffectView
let visualEffectView: UIVisualEffectView = UIVisualEffectView(effect: UIBlurEffect(style: .Light))
visualEffectView.frame = backdropEffectView.frame
backdropEffectView.superview?.insertSubview(visualEffectView, aboveSubview: backdropEffectView)
backdropEffectView.removeFromSuperview()
}
I would like to have a UITableView in a navigation controller occupying the entire screen. I have a smaller custom UIView which needs to slide up from the bottom, squeezing the table view by 100 pixels. The custom view needs to be static, not moving while the user navigates the tableview. Ive been told not to have 2 UIViewControllers (VC) managing views on the same screen.
Currently, my AppDelegate adds a subview to its window from a VC, which then loads the tableview and custom view with
[self addSubview:tablviewcontroller.view];
[self addSubview:customViewController.view];
How should this be implemented?
the way I would structure this is as follows:
have a UIViewController subclass whose view takes up the entire screen. It will have two subviews.
First subview: The view of the UINavigationController that contains your table view controller.
Second subview: the custom UIView.
Have the UINavigationController's frame initially be set to the entire bounds of the main view controller's view and the custom view's frame just below the visible area of the screen.
When you need to slide up the view, use UIView animation to animate changing the frame of the UINavigationController's view by decreasing the height and change the frame of the custom UIView by changing its y coordinate to now be in-frame.
Okay. You want a navigation controller, of which the root view is a table view. Then, possible by an user input, you want this table view to slide up by 100 pixels, and another view takes place at the bottom. While the other view stays there, the user may keep using the table view.
Here is how I would do it:
Create a generic view controller (let's call it NavigationWithAuxiliaryViewController). The root view of this class covers all your application window.
This view has an instance of UINavigationControlleras its property, say navController. It also has an UIView (for the other view) as its property (say, auxView). Position the other view at the bottom. However, this view is hidden by default. Also, the frame of the root view of UINavigationController covers the entire view.
When you decide to squeeze up the table view, modify frame property of UINavigationController. Do something like this (not this ugly though):
if (slideViewOn) {
[UIView beginAnimations:#"slideUp" context:nil];
navController.view.frame = CGRectMake(0, 0, 320, 260);
auxView.hidden = NO;
[UIView commitAnimations];
} else {
[UIView beginAnimations:#"slideDown" context:nil];
navController.view.frame = CGRectMake(0, 0, 320, 480);
auxView.hidden = YES;
[UIView commitAnimations];
}
The easiest way to squeeze up the whole navigation/table stuff is to modify the whole frame for the navigation controller, which is why you need a separate view (out of the navigation controller) for the other view.