popTOViewController

I have a button named 'HOME'. In that button action I have the following code:

[self.navigationController popToViewController:[self.navigationController.viewControllers objectAtIndex:1] animated:YES];

When I click this button my app crashes.

Changing the index from 1 to 2, then it pops t开发者_JAVA技巧he view perfectly.

[self.navigationController popToViewController:[self.navigationController.viewControllers objectAtIndex:2] animated:YES];

My view sequence is Page1 --> Page2 --> Page3

I want to go from Page3 to Page1 but the app crashes. From Page3 to Page2 it works fine.

Try this.

Where I have written SeeMyScoresViewController you should write your View Controller class on which you have to go.(eg. Class of Home)

NSArray *viewControllers = [[self navigationController] viewControllers];
for( int i=0;i<[viewControllers count];i++){
    id obj=[viewControllers objectAtIndex:i];
    if([obj isKindOfClass:[SeeMyScoresViewController class]]){
        [[self navigationController] popToViewController:obj animated:YES];
        return;
    }
}

If you want to go to the root viewcontroller (page1) just use:

    [self.navigationController popToRootViewControllerAnimated:YES];

Also the first item in an index is not item 1 but item 0:

[self.navigationController popToViewController:[self.navigationController.viewControllers objectAtIndex:0] animated:YES];

This should bring you back to the first viewController, but it will them be easier to use the popToRootViewController method.

Often it is more important to do that from top of stack, so:

In UINavigationController subclass or category:

- (void)popToLast:(Class)aClass
{
    for (int i=self.viewControllers.count-1; i>=0; i--)
    {
        UIViewController *vc = self.viewControllers[i];
        if ([vc isKindOfClass:aClass])
        {
            [self popToViewController:vc animated:YES];
            break;
        }
    }
}

and you call that

popToLast:[SomeViewController class];

An up-to-date way of popping back to a specific controller is:

[self.navigationController.viewControllers enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {

    if ([obj isKindOfClass:[MyViewController class]]) {
        [self.navigationController popToViewController:obj animated:YES];
        *stop = YES;
    }
}];

MyViewController is the controller you want to pop back to.