Don't Pop Navigation Controller in Xcode if AlertView - iphone

Question

I have a Navigation Controller and when I press the back button I don't want to pop the view but I want to show an UIAlertView.I just want to pop the view after having make a choice on the UIAlertView!
How can I do?
I tried to catch the event 'back button pressed' but with no results :(

Answer 1

Create a UIBarButtonItem inside viewDidload and added it to the navigation bar
UIBarButtonItem *backButton=[[UIBarButtonItem alloc] initWithTitle:#"Back" style:UIBarButtonItemStyleBordered target:self action:#selector(backButtonClicked)];
self.navigationItem.leftBarButtonItem=backButton;
create a method which will be called when the backButton is clicked
-(void)backButtonClicked{
UIAlertView *alert=[[UIAlertView alloc] initWithTitle:#"Pop View!" message:#"Are you sure?" delegate:self cancelButtonTitle:#"No" otherButtonTitles:#"Yes", nil];
[alert show];
}
write this UIAlertView delegate method which will be called when the button in the UIAlertView is clicked
-(void)alertView:(UIAlertView *)alertView willDismissWithButtonIndex:(NSInteger)buttonIndex{
if (buttonIndex==1) {
[self.navigationController popViewControllerAnimated:YES];
}
}
NOTE: Dont forget to add UIAlertView delegate in the header file <UIAlertViewDelegate>

Answer 2

You can check for back-button press in the viewWillDisappear method like this (got it from here):
-(void)viewWillDisappear:(BOOL)animated {
if ([self.navigationController.viewControllers indexOfObject:self]==NSNotFound && self.isBackButtonPressed) {
// back button was pressed. We know this is true because self is no longer
// in the navigation stack.
}
[super viewWillDisappear:animated];
Hope this helps!

Answer 3

Implement pop in UIAlertview delegate method clickedButtonAtIndex:
The back button press need to implement only showing the UIAlertview
refer this

Answer 4

follow this code
in button action.
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Message" message:#"Do you want to open?" delegate:self cancelButtonTitle:#"NO" otherButtonTitles:#"YES", nil];
[alert show];
//Alert View delegate method
-(void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if(buttonIndex==0)//NO
{
//your code
}
else if(buttonIndex==1)//YES
{
// your code
}
}