I get the famous loaded the "MyController" nib but the view outlet was not set error. However I made sure, that the IBOutlet view is set.
Once the exception is thrown I hit a breakpoint. Below you can see that
All IBOutlets are connected
All IBOutlets are set
When unfolding UIViewController super-class, I can see that _view is 0x00000000 and obviously causes this exception.
Code (header)
#interface InfoDialogViewController : UIViewController
#property (strong, nonatomic) id episode;
#property (strong, nonatomic) NSString *identifier;
#property (strong) IBOutlet UIView *regularSide;
#property (strong) IBOutlet UIView *flippedSide;
#property (weak) IBOutlet UIImageView *episodeCover;
#property (weak) IBOutlet UITextView *episodeTitle;
#property (weak) IBOutlet UITextView *episodeSummary;
- (IBAction)flip:(id)sender;
#end
Some notes
The xib file contains three UIViews on its root level (Flipped, Regular, View)
InfoDialogViewController.m file doesn't contain any methods (I don't do any funky by overriding)
I am using this Controller in combination with addChildViewController.
Anybody has an idea what happens here and how I can fix it? Does ARC play some tricks on me?
Please check:
1. The Class for your View Controller's View should be UIView
2. File owner should be your View Controller
3. Right CLick on File Owner, your view Outlet should be set.
If it is already solved, can u mention what solved your issue?
Related
When I run my iOS simulator, I get this error:
UITableViewController loadView loaded the I1u-ML-mqb-view-QFc-WC-CU4 nib but didn't get a UITableView.'
My code:
#interface IF2000 : UITableViewController
#property (weak, nonatomic) IBOutlet UILabel *EnterCategory;
#property (weak, nonatomic) IBOutlet UITextField *Tfield;
- (IBAction)Submit:(id)sender;
#property (weak, nonatomic) IBOutlet UITableViewCell *EmptyCell;
#end
This is the only code that I have typed so far. If anyone knows how to solve this problem, I would appreciate the help. If I could get a general answer on how to solve this problem, that would be good as well.
Your nib file contains a view other than a table view as the first object. When you try to load a UITableViewController with a nib, you must make sure to have a table view as the first object.
Why outlet to view called second get nil in willRotateToInterfaceOrientation:duration:? There is two top-level views in the xib, and first and second outlet are pointing to them. Is it not allowed to have two top level view in one XIB? I use XIB with UIViewController. second outlet still exist in viewDidLoad method.
I forget to set up property as strong, instead of weak. And because there is no pointer referring to the second view, it get released.
#property (strong, nonatomic) IBOutlet UIView *first;
#property (strong, nonatomic) IBOutlet UIView *second;
What is the technical difference between them and which is the method recommended by Apple?
// 1
#interface CocoaQuizViewController : UIViewController
{
IBOutlet UILabel *myLabel;
}
#end
// 2
#interface CocoaQuizViewController : UIViewController
{
IBOutlet UILabel *myLabel;
}
#property (nonatomic, retain) IBOutlet UILabel *myLabel;
#end
// 3
#interface CocoaQuizViewController : UIViewController
{
UILabel *myLabel;
}
#property (nonatomic, retain) IBOutlet UILabel *myLabel;
#end
// 4
#interface CocoaQuizViewController : UIViewController
#property (nonatomic, retain) IBOutlet UILabel *myLabel;
#end
The default is (generated automatically if you drag and drop outlet directly from xib to source class):
#interface CocoaQuizViewController : UIViewController
#property (nonatomic, weak) IBOutlet UILabel *myLabel;
#end
All are quite OK.
With new LLVM you are supposed to do 4th one.
#interface CocoaQuizViewController : UIViewController
#property (nonatomic, retain) IBOutlet UILabel *myLabel;
//even you use strong and weak intead of retain,assign,copy
#end
In earlier days, you were doing 1, 2 and 3. Now most of the thing is atomatcally done by the compiler. So your work is now easier than never before.
With New Compiler which comes with XCode4.4 and onwards gives you auto-synthesize for all the properties you declare. ivars also get created prefixed with your property name.
The 4th one, Because Now Apple has recommended all developers to make use of properties.
A couple of thoughts:
Your fourth example avoids a whole category of possible bugs that can plague the first three examples, where you can accidentally end up with two ivars (e.g. if you omitted the #synthesize, the compiler would generate an ivar called _myLabel, your myLabel ivar wouldn't be used, and, thus, would end up being redundant and only serve as a possible source of confusion).
If you use ARC (which I'd encourage, if you can), then clearly that retain reference becomes weak.
You probably shouldn't be "writing" the IBOutlet code yourself anyway. It's just an opportunity to introduce a bug. In IB, click on the "assistant editor" to show your code while working on IB, and then control-drag (or right-click-drag) from the control to the code, and IB will write your code for you! See https://stackoverflow.com/a/15551101/1271826 for screen snapshots.
At least I think it's a basic problem. I just started working with views programmatically.
In RouteCaptureViewController.h:
#property (strong, nonatomic) IBOutlet UIView *routeCaptureSuperView;
#property(nonatomic, weak) IBOutlet UIImageView *captureImageView;
#property(nonatomic, retain) IBOutlet UIImageView *previewImageView;
#property (weak, nonatomic) IBOutlet UIView *captureRouteButtonView;
In my storyboard:
All of the outlets are properly connected, I checked.
I'm implementing addSubview in a method as such and nothing happens:
[self.routeCaptureSuperView addSubview:self.captureRouteButtonView];
[self.routeCaptureSuperView addSubview:self.captureImageView];
The following lines worked previously in the code:
[self.captureImageView removeFromSuperview];
[self.captureRouteButtonView removeFromSuperview];
And I know self.routeCaptureSuperView is not nil from an NSLog.
If I understood you correctly and you removed the views to add them again later I can make an educated guess:
In the moment you send removeFromSuperview to your views they get deallocated because they are declared as weak only.
Weak means that the property will be nil'd if the object is deallocated because the last strong relationship to that object is released.
The parent view is the object that keeps the last strong relationship to those two views.
Try to change weak to strong in the #property declaration of the two subviews.
I have a view controller alertForNeedsClassification as a property in another class, as such:
#interface SCAAppDelegate()
{
HomeScreenViewController * _homeScreenViewController;
NSInteger SCAStatus;
}
#property (strong, nonatomic) PromptClassifyViewController * alertForNeedsClassification;
#end
#implementation SCAAppDelegate
#synthesize alertForNeedsClassification;
#synthesize window = _window;
PromptClassifyViewController's interface looks like this:
#interface PromptClassifyViewController : UIViewController
#property (weak, nonatomic) IBOutlet UILabel *headerTitle;
#property (weak, nonatomic) IBOutlet UITextView *message;
#property (weak, nonatomic) IBOutlet UIButton *notNowButton;
#property (weak, nonatomic) IBOutlet UIButton *classifyButton;
#property (weak, nonatomic) IBOutlet UIImageView *backgroundImageView;
#property (weak, nonatomic) IBOutlet UIView *alertView;
#property NSUInteger tag;
#property (weak, nonatomic) IBOutlet id<PromptClassifyViewControllerDelegate> delegate;
- (void)show;
- (void)showFromView:(UIView *)view;
- (IBAction)show:(id)sender;
- (IBAction)dismiss:(id)sender;
- (IBAction)buttonWasPressed:(id)sender;
- (void)setHeaderTitleWithText:(NSString *)text;
#end
I am trying to change the values of IBOutlets message and headerTitle text, like this:
alertForNeedsClassification = [[PromptClassifyViewController alloc] initWithNibName:#"PromptClassifyViewController" bundle:nil];
//[alertForNeedsClassification setDelegate:self];
self.alertForNeedsClassification.headerTitle.text = #"A title";
alertForNeedsClassification.message.text = #"A message";
Then I show alertForNeedsClassification calling a show method (it's like a custom uialertview, but it doesn't subclass from uialertview).
Thing is, no matter how I change it, the text on alertForNeedsClassification.view is always that which is defined in the nib, ie. I can't change it programmatically.
My custom alert view is based on Jeff LaMarche's design: http://iphonedevelopment.blogspot.com/2010/05/custom-alert-views.html
Any ideas what might be going on?
Please be careful when you allocate and initialize the UIView object, especially if you trying to mix using Nib and dynamically generating objects. The best place is within -(void)awakeFromNib or -(void)viewDidLoad
Also, make sure these methods are called. By using -(id)initWithNibName:bundle: only cannot make sure your view to be loaded. Try -(void)addChildViewController and -(void)addSubview: on parentViewController's view to make sure view is loaded after being initialized.
If the text had to be prepared before being loaded, assign it to separate NSString property within PromptClassifyViewController class. Since this property is independent from view being loaded, you can change it's value BEFORE view is appeared. Make sure this text is used and applied to the headerTitle within -(void)show method.
Since you allocate PromptClassifyViewController and access weak referenced headerTitle from self. alertForNeedsClassification, make sure it's not deallocated right afterward.
Usually, weak option is not used for IBOutlet properties. Though it is used when generating outlet connection code by dragging objects from Interface Builder. Try testing your code using strong.
I was assigning values to the IBOutlets before they were alloc'd/initialized. The solution I implemented was to set the values I needed to non-IBOutlet properties (NSStrings in this case) and assign those where needed, in Prompt...Controller's viewDidLoad;