I have deleted my nib file from my UIViewController and now I want to make it so that it calls init instead of initWithNibName. However, even after I deleted my UIViewController, it is still calling the initWithNibName. What do I need to do to change this so that it calls init?
I initialized the rest of the UIViewController via code, in my UITabBarController I have the following:
- (void)viewDidLoad
{
[self setTabURLs:[NSArray arrayWithObjects:#"tt://mygroup",
#"tt://all",
#"tt://search",
nil]];
}
Three20 framework always calls initWithNib, even if the TTViewController is created without a nib file.
Just move your initialization code into the - (void)loadView function as you need to.
Why does it matter to you what init method is called? Just take the code you would put in init and put it in initWithNibName:bundle.
Find where UIViewController is being allocated and initialized and change it to init instead of initWithNib.
Related
I have a subclass of UIViewController that I want to add from the storyboard.
So I'm using what seems the standard methodology:
SubViewController *svc = [self.storyboard instantiateViewControllerWithIdentifier:#"SubViewControllerID"];
[self addChildViewController:svc];
[self.view addSubview:svc.view];
Which is fine but what if I want to call a custom init method on the subview?
I can do something like:
svc = [svc initWithFoo:#"Hello"];
Which seems to have to go after the addSubview call inorder for it to work.
Is this the best way to do this?
Seems a bit unorthodox. Calling an init method on an object that has already been created seems like its no longer truly an init method.
Maybe I should call it setWithFoo: or something and not have it return anything?
SubViewController *svc = [self.storyboard instantiateViewControllerWithIdentifier:#"SubViewControllerID"];
will cause the SubViewController to be inited with it's - (id)initWithCoder:(NSCoder *)decoder {} method.
Override that method (don't forget to call super)
If you want to do additional setup to your view controller after you instantiate it form the storyboard you can create some methods in the view controller's class and call them after the instantiate method fo the storyboard.
But be careful, if you try to make changes on any UI component in those methods, they wont be applied, and probably the app will crash. So use those methods to set params to the View Controller like array of objects, or any kind of data, and apply the UI changes for the view controller's view in viewDidLoad/viewWillAppear/viewDidAppear methods of your view controller.
Essentially I think the answer is that you can't use custom initialisers on ViewControllers added from the storyboard. Instead you have to set properties directly or through a method at the appropriate time in the life cycle as stated above.
Also as mentioned, the VC will be instantiated through initWithCoder, so calling an additional initialiser might be superfluous(?).
I encountered problems trying to use a custom initialiser that contains a call to super if I called it before the subview was added. I would just get a blank view added, I think because the superclass doesn't seem to know about the storyboard at that point. I had more success removing the call to super but that seems wrong.
This case would be more pertinent when adding subviews to a scrollview. For simplicity I left this out of my example.
Let me try and explain this. Within a project folder has .m and .h files (we all know that haha) however when you start a new ".m" with a xib like for example:
ViewTwoController *loginView = [[ViewTwoController alloc] initWithNibName:#"contentscreen" bundle:nil];
[self presentModalViewController:loginView animated:YES];
[loginView release];
I was wondering how do I create a method that runs as soon as that class (if I can call it that, I'm new to objective C) similar to a main method that Java would have. I want to run some code as soon as that .m has been called and started. Any help would be valued thanks :)
To be safe try to put this in - (void)viewDidLoad
Everything that happens here happens when the view is loaded onto the screen.
Note that there are number of places where you can put your method, in viewWillAppear or in your AppDelegate etc. But I found putting UI elements like your login popup better in viewDidLoad
Hope this helps...
You can add additional code in viewDidLoad method, which is called as soon as your view controller has been loaded.
Using the initWithNibName:bundle: method, your view controller will be automatically loaded and initialized.
I don't really know if what I'm doing is the right way to do it. Right now it seems to be working until it hits a certain point with a EXC_BAD_ACCESS message.
I'll describe what I'm doing as best and with the most relevant details I can tell:
I have a CalendarViewController that inherits UIViewController which is loading from a .xib file (CalendarViewController.xib). The class contains a UIView called contentView which I created and which I initialize with another nib file based on a class which is also inherited from UIViewController:
- (void)viewDidLoad {
[super viewDidLoad];
calendarView = [[CalendarView alloc] initWithNibName:#"CalendarView" bundle:nil];
[contentView addSubview:calendarView.view];
}
(calendarView is the class inheriting UIViewController and viewDidLoad is from CalendarViewController.
CalendarView.xib has a UITableViewController with it's respective UITableView. This Table View Controller is linked to a CalendarTableController to which I also generated a .xib file for it.
Everything is being created just right (apparently) but it is crashing somewhere very unexpected. CalendarTableController also implements a DateLoaderDelegate which loads information from an xml on an external url.
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
// When the data has all finished loading, we set a copy of the
// loaded data for us to access. This will allow us to not worry about
// whether a load is already in progress when accessing the data.
self.lastLoadedMatchXMLData = [self.matchXMLData copy];
// Make sure the _delegate object actually has the xmlDidFinishLoading
// method, and if it does, call it to notify the delegate that the
// data has finished loading.
if ([_delegate respondsToSelector:#selector(xmlDidFinishLoading)])
{
[_delegate xmlDidFinishLoading];
}
}
The application is getting to this point without any problem. _delegate is containing the correct object (a CalendarTableController which implements the DateLoaderDelegate). But when it arrives to the line:
if ([_delegate respondsToSelector:#selector(xmlDidFinishLoading)])
it crashes with the EXC_BAD_ACCESS, I don't really know the reason, if I look at the debugger, the crash is not occurring in any of my classes as any of them are appearing in the execution stack. URLConnectionClient seems to be generating it, but I don't really know why. The loading of the xml had worked earlier before I rearranged the ViewControllers to work as I have described now.
Any ideas?
It's weird. I fixed the problem but I had to dedicate the whole UIViewController to contain the UITableView. What I did was this:
Create an IBOutlet with the custom UITableViewController (CalendarTableViewController) in the custom UIViewController.
In the loaded .xib file I linked the IBOutlet to a created UITableViewController declared as a CalendarTableViewController.
This way I solved the problem of the UITableViewController being deallocated without reason. But now the image views I had placed in the intermediate UIViewController wouldn't appear. I had to set that UIViewController to contain solely the CalendarTableView and place the image views in the initial UIViewController. Weird, isn't it? I don't like much the hierarchy I created... but for now that will do =S
Check that you have defined properties for all of your subviews and that you are retaining everything that you need to be. Bad Access May mean that you're attempting to call respondsToSelector on an object that has been released.
Have you tried calling loadView before adding the nested controller's view to the parent's view?
Maybe viewDidLoad is not executing before you add the view and some variables were never initialized.
when overriding the loadView method in UIViewController, should one call [super loadView] in the beginning of the method or at the end of the method? And why?
According to the UIViewController class reference, you should not call [super loadView] at all:
Your custom implementation of this method should not call super.
Normally you should not call loadView directly. It merely sets your self.view property and is called by the view controller only.
You should call [super loadView] only if you need the view created by your super class, because you want to include it in your decoration view hierarchy or something like that.
Just to be really sure, you didn't mean viewDidLoad, right? Because they are two very different methods... as of 3.0, the docs reccomend always calling viewDidLoad at the start.
You can call it either before or after, but usually it is placed at the end unless you have a reason to do otherwise.
When I need to load a view programmatically I do the following:
MyController* myController = [[MyController alloc] init];
[[NSBundle mainBundle] loadNibNamed:#"myNib" owner:myController options:nil];
// use my controller here, eg. push it in the nav controller
This works fine, but my controller's viewDidLoad is never called. So I resorted to manually calling it after the loadNibNamed call, but it doesn't seem correct. I was expecting the framework to call the viewDidLoad on my behalf. Is this the right way or I'm missing something?
I am new to Stack Overflow, but I discovered this question and discovered a couple other methods to load a nib file that ensure that the viewDidLoad method gets called automatically. Ed Marty's answer is correct, but it requires you to go outside the ViewController's code to load the nib file, these two examples I offer here allow you to keep your code inside the ViewController's implementation. Not necessarily better ways, just different. If you know of any drawbacks to doing it this way, please let me know your thoughts.
First, inside the initWithNibName:bundle: method of your UIViewController subclass, you can replace the call:
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
with something like this: self = [super initWithNibName:#"NameOfAlternateNibFile" bundle:nibBundleOrNil];
Or, you can accomplish what appears to do exactly the same thing by the following:
[[NSBundle mainBundle] loadNibNamed:#"NameOfAlternateNibFile" owner:self options:nil];
[self setView:self.view]; //this line ensures that the viewDidLoad method is called
The key is in understanding what is written in the comments above the function definition for $initWithNibName:bundle: in the UIViewController.h file (included at the bottom of my answer here, see italics).
The nice thing about doing this using either of these methods is that viewDidLoad gets called in either scenario.
Here are the directives listed in UIViewController.h:
The designated initializer. If you
subclass UIViewController, you must
call the super implementation of this
method, even if you aren't using a
NIB. (As a convenience, the default
init method will do this for you, and
specify nil for both of this methods
arguments.) In the specified NIB, the
File's Owner proxy should have its
class set to your view controller
subclass, with the view outlet
connected to the main view. If you
invoke this method with a nil nib
name, then this class' -loadView
method will attempt to load a NIB
whose name is the same as your view
controller's class. If no such NIB in
fact exists then you must either
call -setView: before -view is
invoked, or override the -loadView method to set up your views programatically.
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil;
You should load view controllers with
MyController* myController = [[MyController alloc] initWithNibName:#"myNib" bundle:nil];
Make sure your MyController extends from UIViewController, and the View property is set properly in Interface Builder.
The views are loaded lazyly by UIViewController. If you use the accessor myController.view in your code, the view should be loaded and viewDidLoad be called.
I noticed the same thing. I think ViewDidLoad must be called by the view CONTROLLER. Since you don't have a view controllr in your nib, you have to call the viewdidload manually. I"m having to do the same thing.