i have a root view controller that inserts a subview at index 0 at its viewDidLoad method.
i am trying to get the subview to become firstResponder, but can only do this - from my understanding - in the subview's viewDidAppear method.
here's the line of code i added to the root view controller's viewDidLoad method:
[self.view insertSubview: subViewController.view atIndex: 0];
the subviewcontroller has a xib, subViewController.xib, that is shown correctly at runtime. nevertheless, the subViewController's viewDidAppear does not get triggered.
any idea why this happens? any idea how to remedy this - apart from calling viewDidAppear manually (doing so results in failure to become firstResponder)?
thanks,
mbotta
You have to push the view controller on to a navigation stack in order for it's delegate methods to get called. Adding your view controller's view to the subview array won't call them. The first thing you should do is read the View Controller Programming Guide from Apple as this will save you from some headaches you're creating by doing this in a non-standard way.
Instead of adding the view to your root view controller subviews, do this:
SubviewController *controller = [[SubviewController alloc] init];
[[self navigationController] pushViewController:controller animated:YES];
[controller release], controller = nil;
Now your delegate methods will get called. If you don't have a navigation controller as your root view controller, though, this won't work.
If I recall correctly (sorry can't find the place in docs now) -viewDidAppear does not get called for subviews. You must call it manually in the -viewDidAppear method of parent view controller.
Related
I have added following piece of code in a view.
- (IBAction)accept_clicked:(id)sender {
[self.view removeFromSuperview];
self.view = nil;
}
Once accept is clicked, I have removed the own view like this. It worked fine, anyhow is it fine to do like this or It should be removed from another view(parent)?
Don't do this (with self.view) - it doesn't looks good and you might face difficult to find problems. self.view is the main view associated with an UIViewController. So this view to be visible on the screen, you must have shown it somehow: either pushing it to a UINavigationController or presenting it modally with -presentViewController:animated:completion: (IOS5+) or - presentModalViewController:animated:. Showing a view by instantiating a view controller and adding its view to the current view controller's view is not a good practice also:
//Not good
MyViewController *mvc = [[MyViewController alloc] init];
[self.view addSubView:mvc.view];
In your particular case I suppose you are showing some terms and conditions (or something similar) and have an accept and deny button, your best solution would be to present your view controller from somewhere, implement a delegate method, so the presenting view controller can have the result and then in your -accept_clicked: method to use either [self dismissModalViewControllerAnimated:YES] or [self dismissViewControllerAnimated:completion:] (IOS5+),
I copied a working viewcontroller class from another project into a new project. I can't get the view to load in the new project. In the old project I used presentModalViewController. In the new I cannot get the view to load using either presentModalViewController or presentViewController
I am trying to load the present the view from my main view controller.
Here is what my main view controller interface looks like...
// ViewController.h
#import <UIKit/UIKit.h>
#import "RequestDialogViewController.h"
#interface ViewController : UIViewController <RequestDialogViewControllerDelegate> {
}
- (void)requestDialogViewDidDismiss:(RequestDialogViewController *)controller withResponse:(NSString*)response;
I am using presentModalViewController like this...
RequestDialogViewController *requestIPViewController = [[RequestDialogViewController alloc] initWithNibName:#"RequestDialogViewController" bundle:nil];
navigationController = [[UINavigationController alloc] initWithRootViewController:requestIPViewController];
[self presentModalViewController:navigationController animated:YES];
and presentViewController like this...
RequestDialogViewController *requestIPViewController = [[RequestDialogViewController alloc] initWithNibName:#"RequestDialogViewController" bundle:nil];
[self presentViewController:requestIPViewController animated:YES completion:nil];
What am I missing in the new project? The init method fires, but viewDidLoad does not and nothing is displayed.
Thanks
If ViewController is the root view controller, it can't present a modal view controller from within its own viewDidLoad, because at that point it doesn't have information like the screen size.
If other view controllers have already displayed, this will work. If the root view controller is a UINavigationController, you will see a view sliding in from the right while the modal view slides up from the bottom.
Anyway, for your ViewController, the soonest you could present it is after it has become visible. Using a timer for this is unreliable; older and slower devices have dramatically longer load times.
For more reliability, implement viewDidAppear: for ViewController. Do still use your timer system to add an additional delay; a fraction of a second should be sufficient. Although presenting the modal view controller from within viewDidAppear worked for me in the iOS 5.1 simulator, Presenting a modal view controller when loading another ViewController says it sometimes doesn't happen.
I have it resolved. I was trying to present the view from view did load of the main view controller. Not sure why it does not work there, but instead I am now setting a timer which calls a method to present the view controller after the main view loads and it works fine now using...
[self presentViewController:requestIPViewController animated:YES completion:nil];
Thanks to those who replied.
As #Dondragmer said, if you want to present your viewController in root view's viewDidLoad, it will fail.Once your viewController is ready for that, you can present your new viewController.
So, you can do that in
- (void)viewDidLayoutSubviews {
//present here
}
I encountered the same problem. But my situation is the presentViewController is called after the dismissViewControllerAnimated for another ViewController. My solution is to move the presentViewController to completion block of dismissViewControllerAnimated.
Present a modalViewController:
For the benefit of all starting programmers, type it instead of copy paste.
myVC *viewController = [[myVC alloc]initWithNibName:#"myVC" bundle:nil];
viewController.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:viewController animated:YES];
[viewController release];
It looks like you were trying to present a nav controller as a view controller in the first sample, then you were using the wrong method in the second one.
I have a view (viewB) that is pushed in using the navigation controller from another view (viewA) using pushViewController as usual, however for some reason, I want viewB's controller to pop the view using [self.navigationController popViewControllerAnimated:YES]; from inside its viewDidLoad method or viewDidAppear method, but none of them works, i.e. nothing happens (there is no crash in the app), however, i have a UIButton in viewB with IBAction that simply calls [self.navigationController popViewControllerAnimated:YES]; if the button tapped it will work and the view is popped off to the previous view !! this IBAction works if I removed [self.navigationController popViewControllerAnimated:YES]; from viewDidLoad or viewDidAppear methods because the popping will release the current view and all of its sub-views from memory.
the question is how can get the current view (viewB) to be popped off to the previous view (viewA) from inside viewDidLoad or viewDidAppear methods ?
thanks you so much in advance.
Try making method
- (void)popSelf {
[self.navigationController popViewControllerAnimated:YES];
}
In viewDidAppear add
[self performSelector:#selector(popSelf) withObject:nil afterDelay:0.0f];
This will add selector to runloop, so it will be performed after viewDidAppear.
I have a UIViewController with this method:
-(void)prepareToShowVault {
...
UINavigationController *passcodeNavigationController = [[UINavigationController alloc] initWithRootViewController:passcodeViewController];
[self.navigationController presentModalViewController:passcodeNavigationController animated:YES];
[passcodeViewController release];
[passcodeNavigationController release];
}
When called from another method in this UIViewController, it works just fine. But when called from another UIViewController, this method fires but the code doesn't display a new modalViewController, presumably because the UIViewController with the above method isn't active. How can i make this work?
In the UIViewController docs it says
modalViewController
The controller for the active modal view—that is, the view that is temporarily displayed on top of the view managed by the receiver. (read-only)
So I would guess that unless your view controller is the active one you will not see the modal view that it presents.
Therefore you need to either be in that view controller or add the method to the other view controller as well possibly using a category that you add to both.
Why are you pushing a navigation controller? A navigation controller is already present. Don't create a navigation controller. I think you should simply be doing-
[self.navigationController presentModalViewController:passcodeViewController animated:YES];
HTH,
Akshay
I'd like to have a view appear when the user clicks a button. The hierarchy I have looks like this:
MainWindow
-UIView
--ScrollView
---ScrollView.pages = UIViews
----UIView (from above assignment)
----TextView
----InfoButton
pages is an NSMutableArry of pageController objects. These hook to a nib. These nibs are the pages that user flicks through in the scroll view.
The InfoButton click is wired up like this:
- (IBAction) infoButton_click:(id)sender{
topView topViewViewController *topView = [[topViewViewController alloc] initWithNibName:#"TopView" bundle:[NSBundle mainBundle]];
//[self.navigationController pushViewController: topViewView animated:YES];
//[self.view addSubview: topViewView.view];
[super.view addSubview: topViewView.view];
[topViewView release];
}
InfoButton is on one of the pages in the ScrollView. I've commented out different code that has been tried. None of it adds the view. Nothing happens. Is there a way to get TopView as the top view in the hierarchy?
Is your goal to add the view as a subview, or to slide on a new view using the navigation controller? I'm going to assume the latter for the moment.
- (IBAction)infoButton_click:(id)sender
{
TopViewController *topViewController = [[TopViewController alloc] initWithNibName:#"TopView" bundle:nil];
[self.navigationController pushViewController:topViewController animated:YES];
[topViewController release];
}
This is correct if you actually have a navigationController. Make sure you actually do. When "nothing happens" in Cocoa, it usually means something is nil. You should check in the debugger or with NSLog() to see if any of these values are nil. It is possible (even likely), that your parent has a navigationController, but you do not.
Classes should always have a leading capital. Do not create a variable called "view" that is of class "UIViewController". This is a sure path to suffering. Objective-C is a dynamic language with limited compiler checks on types. Naming things correctly is critical to effective programming in ObjC.
Based on your comment to a previous answer, you want to present a modal view. You do this by creating a new view "modalView" and calling [topView presentModalViewController:modalView animated:YES].
In a future version of the iPhone OS, which of course I would be unable to comment upon if it were under NDA, you might be able to present a modal view controller with a flip transition by setting a property on the view controller to be presented, which would probably be called modalTransitionStyle or somesuch.