I am using a sticky segmented control at the top of my view controller with a scrollable table view underneath it.
I am setting the navigation bar large title with
self.navigationController?.navigationBar.prefersLargeTitles = false
I would like to minimize the large title text to the navigation bar when the user scrolls. Unfortunately the text will not perform this default behavior because of the segmented control that sticks to the top when scrolling.
My first solution was to manually set the prefersLargeTitles = true/false based on scroll position. This will works however there is no animation which looks bad.
How can I achieve this effect? Is there a way to animate the text moving?
Related
I have a UICollectionView that I want to go under the navigation bar. Basically I want it to ignore the entire top safe area, yet still want it to respect the bottom safe area, as there's a tabbar there. This is how it currently looks:
But I want the first cell to start directly the very top of the screen, under the (translucent) navigation bar and the status bar.
If I set collectionView.contentInsetAdjustmentBehavior = .never, then the top part works great, but then the bottom part of the collection view content is hidden by the tabbar - you can't scroll all the way to the bottom so to speak. So I have to manually add a bottom inset again? How do I get the height of the tabbar, including any bottom safe area on devices that have the home bar? Or is there a better way to tell the collectionview to ignore only the top area for its content inset adjustment?
You just need to set the bottom content inset of the collection view manually, after setting the adjustment behavior to .never.
The correct inset (including the tab bar and any home bar) can be found in safeAreaInsets.
collectionView.contentInsetAdjustmentBehavior = .never
collectionView.contentInset.bottom = collectionView.safeAreaInsets.bottom
You'll need to do this at a point when the safeAreaInsets have been set, such as viewDidLayoutSubviews.
As far as I remember, it used to be possible by simply adjusting the edgesForExtendedLayout property of the containing view controller, but that was phased out when safe areas were introduced in iOS 11 I believe.
I have a UITableViewController embeded in a UINavigationController, with the property navigationBar.prefersLargeTitles set to true. As it would react normally, when you scroll the tableView, the navigation bar will shrink in size, and with it, the large title will get pushed behind the rest of the navigation bar, and a new small title will appear. What I want to do is to change this animation, to make the large title move to the center of the shrunk navigation bar and shrink in size. How could I do that?
I encountered a problem with the scrolling when using the prefersLargeTitles and added UITableView.
If I set the prefersLargeTitles within a navigation controller and its root is a UITableViewController everything is fine, scrolling of the navigation large title works the same way we can see in the system apps (in iOS 11+).
The problem
However, if I use a UIViewController and add a UITableView in it, scroll seems to act differently. Navigation bar is moving more/faster than I actually scroll. It just hides/shows the large title whenever I scroll into a position that just triggers it, so I end up with the totally different feeling.
Turns out that the layout is causing this problem.
The problem occurs if the UITableView use Align top to: Safe Area constraint (besides the bottom, leading and trailing to Safe Area) and is not extended under the bar.
However if I use the extended layout, align top to the superview, I can still use the UITableView and get the correct behaviour of the large title and its navigation bar.
edgesForExtendedLayout = .top
extendedLayoutIncludesOpaqueBars = true
Or use navigation bar's isTranslucent = true which extends it too.
I've got a gradient background that I want to show through both the navigation bar and the tab bar. I have them set to "translucent black". If I create a ViewController and put a TableView on it, this works perfectly. However, I can't get it to work properly with a TableViewController. The tab bar works fine, but the navigation bar ends up black. If I turn off "Adjust Scroll View Insets", then the navigation bar looks the way I want it, but the top half of the first table view row gets cut off (see examples). The gradient is on the background view. The background colour of the tableview is clear.
Is there any way to get the same effect on a TableViewController? Do I need to somehow make the heading or first row of the tableview be the background that goes under the nav bar?
ViewController with TableView added:
TableViewController with "Adjust Scroll View Insets" ON:
TableViewController with "Adjust Scroll View Insets" OFF:
After doing a test I think you'd need:
Adjusts Scroll View Insets ON
Extend Edges - Under Top Bars ON
No. 1 allow the UITableView to cover the entire screen (including under the navigation bar) and No. 2 adds a space at the top of the UITableView content so that the content is not hidden under the navigation bar.
I ran into a similar issue trying to set a full screen background on a static table view controller with a clear navigation bar. I solved it by using a backgroundView on my tableView instead of setting backgroundColor. For example:
myTableView.backgroundView = UIImageView(image: UIImage(named: "backgroundImg.png"))
I set my navigation bar to clear, but you could style that however you like:
navigationController?.navigationBar.backgroundColor = UIColor.clear
I also had to set Extend Edges - Under Top Bars ON
I am trying to add a UIImageView to the back of a navigation bar.
The reason is because I want to create a UITableView whose navigation bar is actually a picture (with back button on the left) but I want the picture to scroll with the tableview and when the picture is fully scrolled out. The navigation bar is shown as per normal.
My solution to this problem:
Add a UIImageView to the top of the UITableView and make the navigation bar transparent. Set a contentOffset for the UITableView which is a subclass of UIScrollView so that when the view is presented, it looks like the picture is filling the navigation status bar.
Problem:
If I scroll up, instead of bouncing back, the transparent status bar is shown (with a color of the background as it is transparent).
Possible way to solve this new problem:
I was thinking of trying to limit the ScrollView size to get around with problem but failed.
So I feel is it possible to add the UIImageView to the "back" of the navigation bar so that it is there without any offset? Since that way, my life will be much easier.
Any suggestions on solving this or another new approach to get the same UI/effect?
Related question.
I would do this by adding either a table header or cell at the top of the table which contains your image.
Create the table view so that it extends all the way to the top of the screen. Extend Under Top Bars option. I have not done this with a UITableViewController but I have done this with a UITableView embedded inside a UIViewController's view with the top constraint set to 0 for the view rather than the top layout guide.
Now when you run this your table will fill the whole screen and the top header or cell will be at the top showing your picture.
When you scroll you can either use the UIScrollViewDelegate to detect the movement or implement tableView:didEndDisplayingCell:forRowAtIndexPath:
I'm not 100% sure when you want the navigation bar to go non clear. If its when the image goes off screen then didEndDisplayingCell should be good. If its when the cell bottom passed under the bottom of the navigation bar then scroll view might be your only option.
This will also bounce as you expect when you pull down and it should snap back to the top.
Hope this helps.