Question

I have a viewcontroller(say A). I am pushing some viewcontrollers over the first viewcontroller(A). After some tasks, I am switching back to my first view controller(A). That is, I pop to rootviewcontroller(A). But this time my viewcontroller(A) should have an alertview.

My question: Is setting a global boolean variable the right way to go in this case. I mean, I declare a global boolean variable which sets to true, only when the viewcontrollers are popped out. Is there a better way I could do this.

Answer 1

Sure you may use Global NSString(or BOOL) for showing the AlertView when comes to ViewController
Here in Below code i used the String variable.
Declare a NSString variable in AppDelegate.h Class

NSString * checkAlert;
//make property of that NSString.
@property(retain,nonatomic)NSString * checkAlert;

In AppDelegate.m

//synthesize checkAlert
@synthesize checkAlert;

checkAlert=@"NotNeed";

then in ViewController

-(void)ViewWillAppear{
// here check if checkAlert contains string as you want
if(checkAlert isEqualToString:@"showAlert"){
 //here show the AlertView
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Alert" message:@"AlerViewmessage" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];

    [alert show];
    [alert release];
}
}

//when you abou to navigate to another ViewController the Access that checkAlert String    as
-(void)goToAnotheViewController{
AppDelegate* appdele=(AppDelegate*)[[UIApplication sharedApplication]delegate];
appdele.checkString=@"showAlert";

//then navigate to viewController
[self.navigationController pushViewController: animated:YES];
}

//you just need to compare checkString's value string . 

It’ll work