As what I said above. I encountered a problem that I have to dismiss the popover on screen while I don't know where it come from.
What I want to do is : when the app become inactive, I want to dismiss the popover. But I don't know where the popover is presented, and which controller is responds to it?
Is there a notification which I could listen to when the UIPopover is presented?
Or can I find the Popover on the screen?
Thank you guys.
Just subclass your own implementation of UIPopoverController and overridepresentPopoverFromRect:inView:permittedArrowDirections:animated and presentPopoverFromBarButtonItem:permittedArrowDirections:animated and keep track of popover references in a global array. Since Apple's HIG says only one popover is allowed at a time on screen, you only need to track the last one.
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I have an iPad app that uses a UIPopover from within a UIVIew; I need to show an alert-type message when a certain condition has been met.
The problem is using a UIAlertView from within the UIPopover, when the user taps on a button in the UIAlertView, it also dismisses the UIPopover, which defeats the purpose of the alert.
I tried using UIActionSheets, but they don't display at all, probably because they are not being called from a controller-type view.
Is there a way to circumvent this behavior?
No, and you shouldn't do that. Popovers are supposed to go away as soon as you touch anything else.
You could enlarge the popover slightly and make room for a status message. When the user creates an appointment that overlaps, you could display a message in the status area.
Or, you could dismiss the popover and display an alert with "ok"/"cancel" buttons. The OK button would create the overlapping appointment, and the cancel button would discard it.
You will need some place to save the info from the popover while you are waiting for the user to decide what to do with the alert. Perhaps have the popover pass a message back to the view controller it comes from, and then have the source view controller create the alert, set itself as delegate, and handle the responses from the user.
According to Apple's Human Interface Guidelines, it is OK to display a UIAlertView on top of a popover:
https://developer.apple.com/library/ios/documentation/userexperience/conceptual/MobileHIG/Alerts.html
To quote specifically:
On iPad, don’t display a modal view on top of a popover. With the
possible exception of an alert, nothing should display on top of a
popover.
Displaying a UIAlertView from a popover does not automatically dismiss the popover. There is likely some of your own code being executed which is causing it to dismiss. For example, in a similar situation I had, I found that displaying a UIAlertView was invoking "shouldAutorotate" in my split view controller, and (due to earlier iOS bugs) I had placed code there to dismiss the popover. For iOS7+ this was no longer necessary, so I was able to move this code into willRotateToInterfaceOrientation, where it no longer causes dismissal of the popover upon display of UIAlertView, because in this case, even though "autoRotate" gets called "willRotateToInterfaceOrientation" does not.
I have an app I am working on that has a main screen with two buttons. One will take you to a view of a GPS (map) and then once there (new VC) it has options for setting that position or bringing up a list (tableview, another VC) of all locations already tagged.
At the list VC, if you click on the table cell, it will bring up the VC with the map. Problem is, this then adds the same VC bak on the stack. If a user clicks the Cancel button, they go back ones screen, then cancel goes back another screen, etc... until back to the main.
I know I can do the [self.navigationController popToRootViewControllerAnimated:YES]; to pop back to root but that is not always what I want.
Also, I know I can do: [[[self presentingViewController] presentingViewController] dismissModalViewControllerAnimated:YES];
I guess what I am saying is I want to "reuse" the GPS map view so I can call it from other VC's, so that is why I didn't go with the "pass back" to calling VC. So, is there away to either when a button is pressed and is to present a new VC, can I dismiss the prior one after the new one is shown? This way, a dismiss of current VC would take me back to where I need to be.
I hope makes sense and also that this question doesn't fall into the "Not an actual question" category.
Any help or better suggestions is greatly appreciated. Thx
Geo...
If you want to jump back some number of levels in a navigation controller's VC stack, you'll probably want to use its popToViewController:animated: method. To figure out if a particular view controller is on that stack, look at the navigation controller's viewControllers property. Be careful, though, as this kind of jumping around is a rather nonstandard UI behavior (even though there's API for it) which might confuse your users.
Also, using navigation controllers and presenting modally aren't the only ways to manage multiple view controllers -- you can always set the window's rootViewController yourself (and animate the change with UIView animations), even wrapping up your custom transition type in a custom UIStoryboardSegue if you like.
You can put a delegate in the table view. So that when a cell is pressed the info is passed to the delegate method in the VC which will dismiss the table view and reloads itself with the new info. You will have to implement refresh method in that VC.
I'm trying to determine when a UIBackButton is pressed in a sublayer of a navigation app. Would HitTest be used for that? I've seen reference to HitTest, but not exactly sure what it is and how to code for it. Any help is muchly appreciated. Thanks!!
No. Hit testing is the (recursive) process by which UIKit determines which view receives touch events. You shouldn't need to participate in it or invoke it.
If you're using a UINavigationController, it will do the right thing to transition between view controllers when the back button is pressed. If an individual view controller needs to know when it is transitioning off-screen, it should override the -viewWillDisappear: and -viewDidDisappear:. See the documentation for those methods for more information.
Must I always resignFirstResponder for a UITextView? Or, will this happen automatically when its view controller disappears?
I'm asking because I'm having an issue similar to iPhone Objective-C: Keyboard won't hide with resignFirstResponder, sometimes, where the keyboard stays up even when the nav controller pushes and pops other view controllers. The keyboard works, and when I hit done, it unfocuses the UITextView (i.e., the cursor disappears), but the keyboard stays up.
I never found out why this is happening, but maybe it's due to not doing resignFirstResponder before pushing another view controller, but I thought it was optional?
At a total guess, the UITextView has a reference to the view controller (as its delegate) but does not retain it. When you go to the next screen, the controller is dealloced and then the UITextView (which has perhaps been retained by something else) tries to call back to the dealloced controller and crashes. When you call resignFirstResponder, you reverse the order this happens, and therefore no crash.
The way round this to add a textView.delegate = nil call in your view controller's dealloc method - obviously put it before you release the text view.
The contract between a UITextView and it's delegate says that the delegate will send -resignFirstResponder when the text view is done editing. This informs the framework that the view is done editing, fires the events relating to that (willEndEditing and didEndEditing), and allows other parts of the responder hierarchy to react accordingly. Failing to do so might work, but it's not following the contract (that's all a protocol is) it agreed to.
I don't think you have to because the Xcode Sample UICatalog UITextField doesn't call resignFirstResponder before the TextViewController is popped.
The reason the keyboard got stuck for me is that I was having the same view controller present two view controllers modally at the same time, one after the other. UIKit didn't like that.
Calling resignFirstResponder makes sure that the text property contains the actual text shown in the control.
Depending on the state this is not always necessary, but if your controls have resigned first responder, you know that you're working with valid data.
I have a UIViewController that is presented with UIModalPresentationFormSheet. So when the keyboard is visible it stays visible until the view controller gets dismissed.
In that UIViewController I have a navigation controller. So in every UIViewController pushed to that navigation controller I have to check these things:
when the keyboard shows/hides I have to adjust the contentInset
when view appears I have to check if the keyboard is visible or not (the navigation controller remembers that with the notification) and adjust the contentInset. I push UITableViewControllers there, so I don't get viewDidAppear and co. So I have to do all this with the UINavigationControllerDelegate methods?
on every rotation I have to do adjust the contentInset
Otherwise the keyboard may cover some content.
Is that the correct handling? Isn't there any easier solution for this problem? Because this is kind a messy!
I didn't found a better solution, so i did it this way.