When I call loadNibNamed: in init, the UIViewController can't receive viewDidLoad event.
But if I put call to loadNibNamed: somewhere else, it works fine. What is the reason?
-(id)init
{
self=[super init];
if(self){
[[NSBundle mainBundle]loadNibNamed:#"MainView" owner:self options:nil];
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
}
This is because when you are writing implementation of init , you are not calling super with nib name correctly.
-(id)init {
self = [super initWithNibName:#"MainView" bundle:nil];
return self;
}
Related
I have this cascade :
Somewhere in the app
- (void) go
{
MyCustomViewController* controller = [[MyCustomViewController alloc] init];
controller.delegate = self;
[controller run];
}
in MyCustomViewController
- (id) init
{
// there is an if statement here in real to choose another XIB if needed
// but I only display here the code that is called in my tests
self = [super initWithNibName:#"MyXIB" bundle:nil];
if (!self) return nil;
self.delegate = nil;
return self;
}
- (void) run
{
// do things with self.view
}
MyCustomViewController inherits GenericWindowController
in GenericWindowController
/*- (id) initWithNibName:(NSString*)nibNameOrNil bundle:(NSBundle*)nibBundleOrNil
{
if (!(self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil])) return nil;
self.view.userInteractionEnabled = NO; // THE APP CRASHES HERE ! self.view is nil
...
return self;
}*/
// METHOD created following first answers : NOT CALLED
- (void) viewDidLoad
{
self.view.userInteractionEnabled = NO;
// and many other things done with self.view
}
MyXIB has its File's owner set to MyCustomViewController and the view is connected.
All files are included and checked into the project.
GenericWindowController is designed to make some standard stuff.
MyCustomViewController extends this stuff to work with a custom View, as designed in MyXIB.
Why self.view is nil in GenericWindowController ?
Why viewDidLoad is not called ?
A view controller should not try to access its view in initWithNibName:bundle:. It should wait until viewDidLoad.
self.view is only valid after viewDidLoad -- in init... it is still nil.
Incredible !!! The problem was because of a missing localization for the XIB. Added the localization, and no problem anymore.
I am trying to push an opengl UIView to my navigation controller like this
GraphViewController *gvc = [[GraphViewController alloc] initWithTicker:[listOfItems objectAtIndex:indexPath.row]];
[self.navigationController pushViewController:gvc animated:YES];
[gvc release];
The initWithTicker method looks like this
-(id) initWithTicker:(NSString*)ticker{
self = [super initWithNibName:nil bundle:nil];
if (self) {
self.title = ticker;
EAGLView *eagl = [[EAGLView alloc] initWithFrame:[UIScreen mainScreen].bounds];
eagl.animationInterval = 1.0 / 60.0;
[eagl startAnimation];
self.view = eagl;
}
return self;
}
When I go back and forward in my UINavigationController, the drawView method (in EAGLView) keeps looping. Furthermore, if I pushViewController again, the first one does not stop and a new one is created! I've tried making this an instance variable so only one is created and it has the same effect. I would be grateful if anyone has insight as to why this is happening
sergio Suggestion:
-(id) initWithTicker:(NSString*)ticker{
self = [super initWithNibName:nil bundle:nil];
if (self) {
self.title = ticker;
}
return self;
}
// Implement loadView to create a view hierarchy programmatically, without using a nib.
- (void)loadView {
eagl = [[EAGLView alloc] initWithFrame:[UIScreen mainScreen].bounds];
self.view = eagl;
}
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
eagl.animationInterval = 1.0 / 60.0;
[eagl startAnimation];
[super viewDidLoad];
}
same behaviour.
---This is how I fixed my drawView looping problem--
-(void)viewDidAppear:(BOOL)animated {
[eagl startAnimation];
[super viewDidAppear:animated];
}
-(void)viewDidDisappear:(BOOL)animated {
[eagl stopAnimation];
[super viewDidDisappear:animated];
}
--Craigs solution --
if(graphView == nil){
graphView = [[GraphViewController alloc] initWithTicker:[listOfItems objectAtIndex:indexPath.row]];
}else{
[graphView release];
graphView = [[GraphViewController alloc] initWithTicker:[listOfItems objectAtIndex:indexPath.row]];
}
Are you creating a new GraphViewController every time you want to push one onto your navigation stack? If so, it doesn't really matter how you're handling the creation of your EAGLView instance variable, since you're never going to be interacting with that view controller again anyway.
For example:
User taps something, a new GraphViewController is pushed on the stack
User goes back, this view controller continues to run
Return to 1. and repeat (thus creating a SECOND GraphViewController, and then a third, and then a fourth... etc.)
What you should probably be doing is maintaining your GraphViewController as an instance variable, and only creating it once. This will ensure that you're in turn only creating one EAGLView.
if (_graphViewController == nil) {
_graphViewController = [[GraphViewController alloc] initWithTicker:[listOfItems objectAtIndex:indexPath.row]];
}
[self.navigationController pushViewController:_graphViewController animated:YES];
Then, be sure to release the view controller in your dealloc method if you're going to be maintaining it as an ivar.
Would you try executing this code of yours:
EAGLView *eagl = [[EAGLView alloc] initWithFrame:[UIScreen mainScreen].bounds];
eagl.animationInterval = 1.0 / 60.0;
[eagl startAnimation];
self.view = eagl;
inside of loadView? I am not sure about why your view is behaving like you say, but that is the place where you are supposed to build your UI... so it might make a difference...
Furthermore, I would call [eagl startAnimation]; only in viewDidLoad...
Hope it helps...
I am trying to implement AQGridView based upon the ImageDemo in the /examples folder. I have a view controller with the following declaration:
#interface ImageDemoViewController : UIViewController <AQGridViewDelegate, AQGridViewDataSource, ImageDemoCellChooserDelegate>
{
...
None of the datasource methods in my view controller such as
- (NSUInteger) numberOfItemsInGridView: (AQGridView *) aGridView
{
return ( [images count] );
}
are being called. Here is where I setup the gridview making my view controller the delegate for the gridview.
- (void)viewDidLoad
{
[super viewDidLoad];
self.gridView.autoresizingMask = UIViewAutoresizingFlexibleWidth|UIViewAutoresizingFlexibleHeight;
self.gridView.autoresizesSubviews = YES;
self.gridView.delegate = self;
self.gridView.dataSource = self;
images=[[NSMutableArray alloc]init];
[images addObject:#"http://t3.gstatic.com/images?q=tbn:ANd9GcTOXAzFMoK441mcn9V0OemVe_dtAuCpGjBkLrv4rffyOjYIo45BEw"];
[self.gridView reloadData];
}
If I set a breakpoint on
[self.gridView reloadData];
the line is executed but reloadData method in AQGridView is not called. The only difference from the ImageDemo is I do not have a .xib file for the view controller. Have I forgotten to hook up something, resulting in the datasource methods not being called?
If there's no XIB, then who's creating the gridView? If it's never created, then it would be NIL, and you'd have the behavior you describe. (If that's it, then just adding:
self.gridview = [AQGridView alloc] initWithFrame: ...]; should suffice.
Had the same problem. Solved by replacing the view with the AQGridView.
[self.view addSubview:self.gridView]
self.view = self.gridView;
Full method:
- (void) viewDidLoad
{
[super viewDidLoad];
self.gridView = [[AQGridView alloc] init];
self.gridView.autoresizingMask = UIViewAutoresizingFlexibleWidth|UIViewAutoresizingFlexibleHeight;
self.gridView.autoresizesSubviews = YES;
self.gridView.delegate = self;
self.gridView.dataSource = self;
self.view = self.gridView;
[self.gridView reloadData];
}
Maybe you could try implementing this:
- (void)LoadSearch
{
NSURL *test1 = [NSURL URLWithString:#"http://www.4ddraws.com/search_iphone.asp"];
NSURLRequest *test = [NSURLRequest requestWithURL:test1];
[web4D setScalesPageToFit:(YES)];
[web4D loadRequest:test];
}
I am having a hell of a job trying to get a delegate setup on a custom view.
This is the init code:
- (id)initWithPageNumber:(int)page {
self = [super init];
if (self) {
UpgradeContentView *v = [[UpgradeContentView alloc] initWithPageNumber:page];
[self setView:v];
[v release];
}
return self;
}
then in viewDidLoad I have this:
- (void)viewDidLoad {
[super viewDidLoad];
[(UpgradeContentView *)self.view setDelegate:self];
}
which does not error and the program runs, but none of my delegate methods get called, I have placed NSLog calls and break points but the delegate seems not to be working.
I am doing this completely wrong?
Thanks
My data is stored in a member variable (NSArray) of a view controller. The problem I'm running into is that my data is loaded from a database on application launch, but the NSArray isn't initialized until later, so the addObject calls silently fail.
I've tried putting breakpoints on the init, initWithNibName, viewWillAppear, and viewDidLoad methods of my view controller (SafeTableViewController), but none of them catch before the addObject call. I assume that the actual view controller is initialized, because when I watch it in the debugger it has a nonzero address, but the NSArray has the address 0x0 when addObject is called.
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
databaseName = #"DubbleDatabase.sql";
NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDir = [documentPaths objectAtIndex:0];
databasePath = [documentsDir stringByAppendingPathComponent:databaseName];
[self checkAndCreateDatabase];
[self readSafeItemsFromDatabase ];
// Add the tab bar controller's current view as a subview of the window
[window addSubview:tabBarController.view];
[window makeKeyAndVisible];
return YES;
}
- (void) readSafeItemsFromDatabase {
// some code skipped here, but basically: open sqlite3 database, iterate through rows
while(sqlite3_step(compiledStatement) == SQLITE_ROW) {
// read database, get data fields out
SafeItem *safeItem = [[SafeItem alloc] initWithName:aName price:aPrice category:aCategory];
[safeTableViewController addItemToSafe: safeItem]; // PROBLEM HERE
[safeItem release];
}
}
sqlite3_close(database);
}
In SafeTableViewController.m:
- (void) addItemToSafe : (SafeItem*) newSafeItem {
[self.safeItems addObject: newSafeItem];
}
// I put a breakpoint on this, but it does not hit. i.e. safeItems is not initialized when addObject is called on it.
-(id) init {
if(self = [super initWithNibName:#"SafeTableViewController" bundle:nil]){
self.safeItems = [[NSMutableArray alloc] init];
}
return self;
}
EDIT: Thought of a way to fix this problem. Still curious though: when is init and/or initWithNibName called? Here's the proposed solution:
- (void) addItemToSafe : (SafeItem*) newSafeItem {
if(self.safeItems == nil){
self.safeItems = [[NSMutableArray alloc] init];
}
[self.safeItems addObject: newSafeItem];
}
How do you setup your instance of SafeTableViewController? By code? By nib?
-(id) init is not the designated initializer.
You probably want to use
- (id)initWithNibName:(NSString *)nibName bundle:(NSBundle *)nibBundle {
if(self = [super initWithNibName:nibName bundle:nibBundle]){
self.safeItems = [[NSMutableArray alloc] init];
}
return self;
}
or initialize elsewhere, i.e. in viewDidLoad.
The problem is that you shouldn't be storing your data in a view controller. Create a model object (SafeItemManager for instance) to hold your data and point the view controller at that.