Question

This is for an addition to a legacy iPhone app with the architecture already defined (years ago, by somebody else.)

The main limitation is that the functionality of the main menu system is based on configuration files, so I can’t call any specific initialisation code from the main menu.

This means that the view I am developing is stand-alone, and has to somehow manage its states with the information from the system.

Further, on each screen there is a “Settings” button, taking the user to a Settings pane, that is pushed on the navigation stack on top of “my” view. When the user closes the settings pane, my view reappears, as per normal navigation.

OK, so here is my problem:

When the user enters my view from the menu I want it to be reset so all input fields are empty.

If the user goes to the settings screen and returns to my screen, I want all previous input to be preserved, i.e., not reset to empty fields.

If the user then goes back to the main menu, and re-enters my screen, fields should be empty again.

Is there a robust, documented and preferably simple way to know if I should reset the fields in this scenario?

Answer 1

Can you check the navigation stack to see if the settings page is currently on the stack?

- (void)viewWillAppear:(BOOL)aAnimated
{
    [super viewWillAppear:aAnimated];

    NSArray* stack = [[self navigationController] viewControllers];

    UIViewController* last = [stack lastObject];
}