In my custom UIViewController I have two distinct UIWebViews for which my custom UIViewController is the delegate. In webViewDidFinishLoad:webView I call [webView sizeToFit] and I can confirm it gets called twice, one for each UIWebView. However, to my great dismay, it only seems to affect the first one that gets called, while the other one remains unchanged. Obviously both their contents exceed the bounds, so I expect them to be resized accordingly.
Now, after lots of hours spent on this issue, how am I even supposed to proceed to understand what's wrong?
EDIT: Alright, apparently the problem is that the view in which I put the second UIWebView is not visible on the screen when I call sizeToFit. Calling it with a delay after the view is shown results in the expected behaviour. Now I have to find a way to do this without showing it, because I need to to be visible at a later time. Ideas?
It seems that doing that on viewDidAppear works like a charm.
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I'm creating a UIView in one of my methods and going through all the steps of adding it to the view:
background1 = UIView(frame: CGRectInset(other.frame, -thickness, -thickness))
background1!.backgroundColor = aColor
background1!.hidden = false
container.addSubview(background1!)
This is included in a method I call in viewDidAppear(). In general, everything works perfectly. This view, however, appears noticeably later when opening the app the first time.
I can tell, from setting breakpoints before and after the above code, that background1 does not appear on the screen immediately after the code is executed, nor even in any place I've been able to set breakpoints.
I'm not doing anything else with the view—for some reason it takes surprisingly annoyingly long to load.
I have a very complicated (as shown by the >114 comments here) layout setup that's part AutoLayout and part programmatic and thus would like to just resolve this issue alone, if possible, without ripping up everything else.
I know that viewDidAppear() is, of course, called after the view appears, meaning the code executed should take effect then, but from what I can tell, background1 isn't even appearing at that point.
Additionally, as you can see in the first line of the code I posted, background1's frame relies upon that that of other, another subview. This view has its frame determined by AutoLayout. From what I understand, it's only guaranteed that the correct frame will be reported after viewDidLayoutSubviews()is called. (Incidentally, this is even called after viewDidLoad().)
I know I've already made a mistake by mixing AutoLayout and programmatic layout, but I'm hoping there's a way to salvage this. I do, in fact, remember, a time in a previous version when nearly the exact same setup was working perfectly. (Looking back through commits, though, I couldn't find it.)
To be clear, I guess I'm asking if there's a way to force the UIView to appear when the code is executed. I've tried calling the parent's layoutSubviews(), but that doesn't seem to work.
Thank you.
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 have a UITextField with custom keyboard, basically like a calculator. I would like my keyboard show up by default, so i used [self.topInputTextField becomeFirstResponder]; in viewDidLoad, I think that's very common usage. However, it causes some very weird actions on my textfield.
When i set my textfield as the first responder in viewDidLoad, and every time after i done editing, the text will jump, and when i click another text field and and click the first text field again, the texts in the first text field sometimes shift down and disappear, but sometimes not. I feel it's very hard to describe, so i recorded a GIF image for it.
And the reason, that I am sure [self.topInputTextField becomeFirstResponder]; causing the issue, is when i comment that line of code out, everything back to normal. here is the GIF after i comment out that line:
that's vert strange to me, between 2 GIF file, the only change i did is comment out that line of code. I couldn't find any solution on SE. Any idea would be very appreciated.
Edit:
One more thing is I tried to change font, and font sizes, they all have similar strange behaviors.
*Edit 2:**
here is how i set up my textfield,i didn't do anything fancy
Try calling the keyboard in viewDidAppear, this method gets called after viewDidLoad. I assume it's because you should only call the keyboard on a loaded view that has appeared to the user, so if you call it before the view actually appears it will cause unexpected behaviour.
viewDidLoad is too early for calling this, the UI hasn't worked out which size your screen is, or even which orientation your device is in. It isn't yet a UI really... Try it in willAppearAnimated: ..
I've been banging my head with this issue for the last two days. Googled a lot but wasn't able to find the answer yet, so I decided to request some help here. Let's see if I get any luck.
I'm coding a reusable control that consists of an UIView with a variable number of customized UIButtons. I implemented initWithFrame:, initWithCoder: and drawRect: where the buttons (which are built prior to drawing) are actually added to the view. Everything is done programmatically since the UIButton content should be supplied when using the control, so there's no XIB for this UIView.
This UIView, let's call it CustomizableBarButton is then used in an UIViewController, let's call it MyTestViewController with a view on it, let's call it customizableBarButtonView.
MyTestViewController's GUI was set on IB where an UIView was tied to customizableBarButtonView (the class was matching accordingly).
MyTestViewController's is a pretty standard class except for the viewWillAppear: that initializes the buttons and passes them to the CustomizableBarButton along with some other options.
The issue is that everything works perfectly...except for the first time!
I mean, when I run the app on the simulator (I haven't tried it on the iPhone yet but I strongly believe that it's not an hardware issue) the MyTestViewController shows the customizableBarButtonView background but not the buttons. Now when you click on the place where a button should be all the buttons suddenly appear!
I'm puzzled since the CustomizablebarButton drawRect: runs before the strange "click n'appear" effect and the buttons are actually added to the subview.
Another hint that my help: if you don't click on the buttons (so you still got no buttons yet) but rotate the device they will also appear as if by magic!
It is probably something very simple but I'm missing it and I'm going nuts...
Can someone lend a hand on this, please?
Thanks in advance!
You said you're adding the buttons in drawRect:. Don't do that. You need to add the buttons in your init methods.
I have always been a bit unclear on the type of tasks that should be assigned to viewDidLoad vs. viewWillAppear: in a UIViewController subclass.
e.g. I am doing an app where I have a UIViewController subclass hitting a server, getting data, feeding it to a view and then displaying that view. What are the pros and cons of doing this in viewDidLoad vs. viewWillAppear?
viewDidLoad is things you have to do once. viewWillAppear gets called every time the view appears. You should do things that you only have to do once in viewDidLoad - like setting your UILabel texts. However, you may want to modify a specific part of the view every time the user gets to view it, e.g. the iPod application scrolls the lyrics back to the top every time you go to the "Now Playing" view.
However, when you are loading things from a server, you also have to think about latency. If you pack all of your network communication into viewDidLoad or viewWillAppear, they will be executed before the user gets to see the view - possibly resulting a short freeze of your app. It may be good idea to first show the user an unpopulated view with an activity indicator of some sort. When you are done with your networking, which may take a second or two (or may even fail - who knows?), you can populate the view with your data. Good examples on how this could be done can be seen in various twitter clients. For example, when you view the author detail page in Twitterrific, the view only says "Loading..." until the network queries have completed.
It's important to note that using viewDidLoad for positioning is a bit risky and should be avoided since the bounds are not set. this may cause unexpected results (I had a variety of issues...)
This post describes quite well the different methods and what happens in each of them.
currently for one-time init and positioning I'm thinking of using viewDidAppear with a flag, if anyone has any other recommendation please let me know.
Initially used only ViewDidLoad with tableView. On testing with loss of Wifi, by setting device to airplane mode, realized that the table did not refresh with return of Wifi. In fact, there appears to be no way to refresh tableView on the device even by hitting the home button with background mode set to YES in -Info.plist.
My solution:
-(void) viewWillAppear: (BOOL) animated { [self.tableView reloadData];}
Depends, Do you need the data to be loaded each time you open the view? or only once?
Red : They don't require to change every time. Once they are loaded they stay as how they were.
Purple: They need to change over time or after you load each time. You don't want to see the same 3 suggested users to follow, it needs to be reloaded every time you come back to the screen. Their photos may get updated... you don't want to see a photo from 5 years ago...
viewDidLoad: Whatever processing you have that needs to be done once.
viewWilLAppear: Whatever processing that needs to change every time the page is loaded.
Labels, icons, button titles or most dataInputedByDeveloper usually don't change.
Names, photos, links, button status, lists (input Arrays for your tableViews or collectionView) or most dataInputedByUser usually do change.