I have a bug in my code and I cannot seem to find it! I've created a button called addButton programatically and set its selector to add—but the app crashes in the simulator every time the button is pressed. Here is my code.
-(void)viewDidLoad{
UIBarButtonItem *addButton = [[UIBarButtonItem alloc]
initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self
action:#selector(add:)];
self.navigationItem.rightBarButtonItem = addButton;
[addButton release];
}
and the code for the add button is :
- (IBAction)add
{
MyDetailViewController * detail = [[MyDetailViewController alloc]init];
detail.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
[self presentModalViewController:detail animated:YES];
//[detail.text becomeFirstResponder];
[detail release];
}
Thanks for the help guys :D
Your add selector has a colon at the end which means it is trying to use an add method with a parameter but your add method does not expect a parameter object. You need to remove the colon from your selector by changing your Bar Button Item allocation to this:
UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:#selector(add)];
Related
I am new at iOS Development.I Have UINavigationController as rootviewcontroller for UIWindow.In the subclass i added UITabbarController programatically.I given default Tabbarcontroller selection as first controller. Here i am trying to add 3 buttons to the navigationbar .
Can any send me the corrent code.
Thanks In advance
To add more than one button on the left or the right side you have to call one of the following methods:
- (void)setRightBarButtonItems:(NSArray *)items animated:(BOOL)animated
- (void)setLeftBarButtonItems:(NSArray *)items animated:(BOOL)animated
The array items contains instances of the UIBarButtonItem class. You can instantiate them like this
UIBarButtonItem *FirstButton = [[UIBarButtonItem alloc]
initWithTitle:#"Title"
style:UIBarButtonItemStyleBordered
target:self
action:#selector(buttonTapped:)];
Then you have to implement the selector buttonTapped: which is called when the button has been tapped.
-(void)buttonTapped:(UIBarButtonItem *)button
{
// do the things that should happen when the button is pressed
}
If you don't want to get them on the left or right side it is also possible to create a UIView by yourself containing the buttons and set the view to be the titleView of the UINavigationItem. This effect is similar to the buttons in the Facebook App
[self.navigationItem setTitleView:yourView];
Here is simple code for add UIButton on UINavigationBar
In Following code you can add Button With FlexibleSpace
NSMutableArray *barItems = [[NSMutableArray alloc] init];
UIBarButtonItem *flexSpace = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:self action:nil];
[barItems addObject:flexSpace];
[flexSpace release];
UIBarButtonItem *btnFirst = [[UIBarButtonItem alloc] initWithTitle:#"First" style:UIBarButtonItemStyleBordered target:self action:#selector(FirstTapped:)];
[barItems addObject: btnFirst];
UIBarButtonItem *btnSecond = [[UIBarButtonItem alloc] initWithTitle:#"Second" style:UIBarButtonItemStyleBordered target:self action:#selector(SecondTapped:)];
[barItems addObject:btnSecond];
UIBarButtonItem *btnThird = [[UIBarButtonItem alloc] initWithTitle:#"Third" style:UIBarButtonItemStyleBordered target:self action:#selector(ThirdTapped:)];
[barItems addObject: btnThird];
self.navigationItem.rightBarButtonItems = barItems;
Button Related Methods
-(void) FirstTapped:(UIBarButtonItem *)sender{
//perform your action
}
-(void) SecondTapped:(UIBarButtonItem *)sender{
//perform your action
}
-(void) ThirdTapped:(UIBarButtonItem *)sender{
//perform your action
}
NOTE : self.navigationItem.rightBarButtonItems Works only in iOS 5 or Latter.
UIButton *customButton = [UIButton buttonWithType:UIButtonTypeCustom];
// here is custom button setup //
UIBarButtonItem *item = [[UIBarButtonItem alloc] initWithCustomView:customButton];
[self.navigationItem setLeftBarButtonItem:item animated:YES];
I have created button for home like this:
UIBarButtonItem * addButton=[[UIBarButtonItem alloc] initWithTitle:#"Home" style:UIBarButtonItemStyleBordered target:self action:#selector(GoToHome:)];
[navItem setLeftBarButtonItem:addButton];
GoToHome function has only one line i.e:
[self.navigationController popToRootViewControllerAnimated:YES];
but when i click the Home button it shows no action (not working)
try this inside your GoToHome method
[self.parentViewController.parentViewController.parentViewController dismissModalViewControllerAnimated:YES];
have you connected the button code with the IB button? that can happen a lot and with everyone..!!
Try this,
UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithTitle:#"Home" style:UIBarButtonItemStylePlain target:self action:#selector(GotoTopScreen)];
self.navigationItem.rightBarButtonItem = addButton;
-(void)GotoTopScreen{
[self.navigationController popToRootViewControllerAnimated:YES];
}
The best way to create a navigation controller is to create it in appDelegate and access it as appDelegate.navigationController. Then those nil object issues do not come.
Use this method:
UIBarButtonItem *flipButtons = [[UIBarButtonItem alloc] initWithTitle:#"Back"
style:UIBarButtonItemStyleBordered target:self
action:#selector(GotoTopScreen)];
self.navigationItem.leftBarButtonItem = flipButtons;
[flipButtons release];
-(void)GotoTopScreen
{
[self.navigationController popToRootViewControllerAnimated:YES];
}
I have a UIButton that pushes to another view controller using the following code. How do I go about putting this UIButton to the top bar of a navigation controller.
-(IBAction) nextButtonPressed {
TipsViewController *objYourViewController = [[TipsViewController alloc] initWithNibName:#"TipsViewController" bundle:nil];
[self.navigationController pushViewController:objYourViewController animated:YES];
[TipsViewController release];
}
I was thinking of adding something like: self.navigationItem.rightBarButtonItem somewhere, but can't figure out the syntax.
Here's something else I tried with the following code: I can get a "Next" button in the top bar of the Navigation Controller. How would I get it to push to another view controller?
UIBarButtonItem *anotherButton = [[UIBarButtonItem alloc] initWithTitle:#"Next" style:UIBarButtonItemStylePlain target:self pushViewController:anotherButton animated:YES];
self.navigationItem.rightBarButtonItem = anotherButton;
[anotherButton release];
thanks for any help.
When you init your UIBarButtonItem, do you see a parameter called action: ? Mention a selector there:
UIBarButtonItem *bar = [[UIBarButtonItem alloc] initWithTitle:#"Next" style:UIBarButtonItemStyleBordered target:self action:#selector(Next:)];
The above item should be your rightBarButton as you want it to be.
And this would be your selector:
-(void)Next:(id)sender {
[self.navigationController pushViewController:nextViewController animated:YES];
}
UIBarButtonItem addButton=[[UIBarButtonItem alloc]initWithTitle:#"+" style:UIBarButtonItemStyleBordered target:self action:#selector(method)];
I have a UITableViewController A that is pushing UITableViewController B onto the stack.
In A i have the code:
self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:#"Trending"
style:UIBarButtonItemStylePlain
target:self
action:#selector(backButtonClicked:)];
backButtonClicked: is also implemented.
B has the title Trending, but when I click it, it doesn't ever reach backButtonClicked:
Why is this?
Try either setting the delegate:
[navigationController setDelegate:self];
Or using the left button. Sometimes the back button doesn't work with certain views and I have had to use the left button instead:
self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:#"Trending" style:UIBarButtonItemStylePlain target:self action:#selector(backButtonClicked:)];
Also, you can try setting B's button item instead of A:
viewControllerB.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:#"Trending" style:UIBarButtonItemStylePlain target:self action:#selector(backButtonClicked:)];
In the Xcode documentation, it states that the backBarButtonItem target and action should be set to nil. So even if you do set it, it's probably a good bet that it will be ignored. You could check out the link below to add custom behaviour to the back button.
Custom Action on Back Button Item
Or you could just do the following in viewControllerB:
self.navigationItem.leftBarButtonItem = [[[UIBarButtonItem alloc] initWithTitle:#"Trending"
style:UIBarButtonItemStylePlain
target:self
action:#selector(backButtonClicked:)] autorelease];
Then also add this to viewControllerB
- (void)backButtonClicked:(id)sender {
[[[self.navigationController viewControllers] objectAtIndex:0] backButtonClicked:sender];
[self.navigationController popViewControllerAnimated:YES];
}
The above method will find the RootViewController and send it the backButtonClicked message. It will then pop the current view controller, which should allow you to emulate the backBarButtonItem. Also you can change which view controller you want to send the message by changing the value in the objectAtIndex method.
try not backBarButtonItem but leftBarButtonItem instead
self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:#"Trending" style:UIBarButtonItemStylePlain target:self action:#selector(backButtonClicked:)];
self.navigationItem.hidesBackButton=YES;
for me it works like a charm. And don't forget that you didn't release this button - and it can cause memory leak. So you can add autorelease when you assign you button or make it like this
UIBarButtonItem *myBackButton = [[UIBarButtonItem alloc] initWithTitle:#"Trending" style:UIBarButtonItemStylePlain target:self action:#selector(backButtonClicked:)];
self.navigationItem.leftBarButtonItem = myBackButton;
[myBackButton release];
self.navigationItem.hidesBackButton=YES;
This doesn't seem to be working. What am i doing wrong?
-(void)awakeFromNib{
UIBarButtonItem *rightBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:#selector(showNewEventViewController)];
self.navigationItem.rightBarButtonItem = rightBarButtonItem;
NSLog(#"awaked");
[rightBarButtonItem release];
}
my guess is, that you add the UIBarButtonItem to the wrong object!
you need to add it, to the rootViewController (instead to the UINavigationController, as you probably did)
YourRootViewController *theRootController = [[YourRootViewController alloc] init];
UINavigationController* navContainer = [[UINavigationController alloc] initWithRootViewController:theRootController];
UIBarButtonItem *btnCancel = [[UIBarButtonItem alloc] initWithTitle:#"Cancel" style:UIBarButtonItemStyleBordered target:self action:#selector(dismiss)];
theRootController.navigationItem.rightBarButtonItem = btnCancel
[navContainer setModalTransitionStyle:UIModalTransitionStyleCrossDissolve];
[self presentModalViewController:navContainer animated:YES];
I would normally put this code in the viewDidLoad method rather than the awakeFromNib method; I'm not sure if that's where your problem lies. What does "not working" mean?
Try this instead:
- (void) initUI {
UIBarButtonItem *btnCancel = [[[UIBarButtonItem alloc] initWithTitle:#"Cancel"
style:UIBarButtonItemStyleBordered
target:self
action:#selector(dismiss)]autorelease];
self.navigationItem.rightBarButtonItem = btnCancel;
//[btnCancel release]; no need to explicitly release the item
}