Forgive me if this is a duplicate. I thought for sure this would be an obvious question.
I have a container in a storyboard, which is of class ModelViewController (the whole view controller). From ModelViewController I need to get the width and height of the container. I am currently trying:
self.view.bounds.size
Which yields 0.563380 and 0.000000. I also tried
self.view.frame.size
Which yields the dimensions of the entire screen. What am I missing here?
From this post
View frames are not actually useable in viewDidLoad; you should move all of your geometry-manipulating code into viewWillAppear. The system will clobber any changes you set in viewDidLoad between there and when it's about tom come on screen.
And the comment
Actually, you should move geometry changes to -viewDidAppear pre-iOS 5 and to -viewWillLayoutSubviews for iOS 5+. -viewWillAppear: may not actually have the correct bounds/orientation if the view is being animated.
I found the solution. The correct dimensions are indeed given when called from viewWillLayoutSubviews. I was calling from viewDidLoad giving incorrect results.
Related
I am trying to setup my UI on my universal app. I have a storyboard setup with size classes, a fairly simple UI. I have my view controller with a view in. Inside this view, I draw a chart so this can only be updated using setFrame.
This is where my problem begins. I set my graph to be the screen width. However, when the view initially runs, the size class seems to be unknown.
As the default 'Any' size in my storyboard is 600x600. My view thinks it should draw 600 wide on my iPhone, which clearly isn't this wide.
It is only after I physically move the iPhone to toggle an orientation change, that it updates and recognises the correct size.
So my question is, how do I prevent this problem? I need my UI to know what size to be from the get go, not just after the user rotates their iPhone.
However, when the view initially runs, the size class seems to be unknown.
It is unknown to the view and the view controller, because at that time the view controller is not yet part of the interface and has no environment. But it is not unknown to UIScreen.mainScreen(). So if you need this information very early, that is who to ask.
However, as you've been advised in a comment, it also sounds like you may simply be doing this too early. Nothing in a view controller's view, including the view itself, has achieved its actual size until viewDidLoad or later.
There are two to prevent this problem
(1) Load your entire method in
-(void)viewDidAppear:(BOOL)animated
{
}
(2) Do the following step
Go to file Inspector
Uncheck "Use size classed
Lately Ive been working with moving my frame to make up for the 20point gap when the status bar is not showing in landscape mode. I have finally gotten what I want, yet there is one problem that kind of annoys me. Let me explain: First I was using a call in viewDidLoad to move the frame, but that doesn't do anything to the frame, because I suppose the frame gets drawn after viewDidLoad. So I tried placing my call in viewDidAppear. That works smoothly, but sadly the user "sees" the repositioning; you can watch the frame being replaced with the bare eye. So I was wondering if theres anything I can do to prevent this, any workarounds. (just for good explanation this call is to take care of view frame when the user updates/go to another view controller when already in landscape. I have other functions to take care of rotation; which obv works)
Any help appreciated. I tried to be as specific as possible.
Thanks!
I know this has been asked before, but none of these solutions work, and that's the reason of my posting. Please do not close before considering my case.
My plist already has UIViewControllerBasedStatusBarAppearance = false.
I have already tried applying deltas, but to no result.
Changing the top level view frame in ViewWillAppear (like self.view.frame) did not succeed.
I thought of increasing the view height (storyboard attribute inspector), in combination with deltas, but my top level view X, Y are disabled in storyboard attribute inspector.
My main view doesn't have any children views because I load them into main view either dynamically or load them from XIBs which are again shared by more than view controllers. These XIBs provide layout for both Portrait and Landscape. I don't know what approach is ideal for this kind of configuration, but I would like it better if solution lies along these lines.
This approach worked partially, but gave me inconsistent results.
What makes the solution tricky is the fact that I have to support all 4 orientations - this is something I handle in code via didRotate and willRotate delegates for my other views, but failing to do it for statusbar.
Please help...
Could this link be of any help?
You might have to use the new setEdgesForExtendedLayout: method to get this working consistently?
Also, have a look at these official docs if you haven't already done so.
I ended up writing my own function to shift my all subviews (remember, not top level views whose frame is fixated by IB).
It didn't spoil my work but imagine if this was the case for a very big project with so many screens, the limitations would have made it a nightmare.
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Why am I having to manually set my view’s frame in viewDidLoad?
I have universal app for iphone and ipad, two storyboards, if I run my app on the iphone simulator in viewDidLoad every frame of each element in nib is correct. But if I do it for ipad (simulator) in frame is nil, but the screen looks correct. Could you please advise me smth? Thanks.
It's a very similar question to ios setContentOffset not working on iPad ... And my answer is the same as there:
"You should not initialise UI geometry-related things in viewDidLoad, because the geometry of your view is not set at this point and the results will be unpredictable.
... viewWillAppear: is the correct place to do these things, at this point the geometry is set so getting and setting geometry-related properties makes sense."
This also applies to getting geometry-related properties. Don't get distracted by it's behaving correctly in one circumstance and not in another... The main point is that setting/getting geometry properties too early will yield unpredictable results.
Your screen looks correct because you are seeing the results after viewWillAppear: / viewDidAppear:.
update (ios6)
When using autolayout in ios6, frames are not set until subviews have been laid out. The right place to get frame data under these conditions is in the viewController method viewDidLayoutSubviews.
This is called after viewWillAppear:. But take care - they are not always called together. For example, viewDidLayoutSubviews is called after a rotation, viewWillAppear: is not. viewWillAppear: is called every time a view becomes the visible view*, viewDidLayoutSubviews not necessarily (only if the views needed relaying out).
(* unless the app was backgrounded and is becoming the foreground app, then viewWillAppear: is not called)
I figured it out why it happened. I was using AutoLayout. When I uncheck it in the storyboard then the frames are correct.
I have a custom UIView, which I have placed using Xcode (4). I need to set some default state, based on the actual bounds of the view. During awakeFromNib, bounds seems to be returning the size of the view in the storyboard layout in Xcode.
The view is in the detail side of a UISplitViewController, which in Xcode is the size of a full portrait iPad screen, but if the app loads in landscape mode then, via springs-and-struts, its size is changed, but this appears to happen after awakeFromNib.
Should I be setting this state in some other method?
It depends what sort of state you are setting - if it is dependent on the bounds then you'll need to reset it every time the device is rotated, presumably? In that case overriding setFrame: might be a better bet - be sure to call the superclass implementation before you do anything else, though.
The answer is was probably looking for, or at least the solution I have used, is to provide a public method in the UIView to be called by the parent UIViewController in viewWillAppear: