iOS Programmatically Creating a View - ios

Question

I am trying to create a new UIView programmatically from one of my .m files and then return to my existing view after 5 seconds. It seems that my logic is off because this is not doing what I am wanting. My code is below.
UIView *mainView = self.view;
UIView *newView = [[UIView alloc] init];
newView.backgroundColor = [UIColor grayColor];
self.view = newView;
sleep(5);
self.view = mainView;
It seems that it is just going to sleep for 5 seconds and then not doing anything.
I want to do the following,
Store starting view
Create new view
Show gray view
Wait 5 seconds
Show my original view
Where am I going wrong? I feel like it has to be my logic or I am missing a key part of these steps.
Thanks for any help! :)

Answer 1

First of all DO NOT USE sleep(). You should use performSelector:withObject:afterDelay: method. Something like this:
-(void)yourMethodWhereYouAreDoingTheInit {
UIView *mainView = self.view;
UIView *newView = [[UIView alloc] init];
newView.backgroundColor = [UIColor grayColor];
self.view = newView;
[self performSelector:#selector(returnToMainView:)
withObject:mainView
afterDelay:5.0];
}
-(void)returnToMainView:(UIView *)view {
//do whatever after 5 seconds
}

Answer 2

Using GCD yields far more readable code, but ultimately its a matter of preference.
// Create grayView as big as the view and add it as a subview
UIView *grayView = [[UIView alloc] initWithFrame:self.view.bounds];
// Ensure that grayView always occludes self.view even if its bounds change
grayView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
grayView.backgroundColor = [UIColor grayColor];
[self.view addSubview:grayView];
// After 5s remove grayView
double delayInSeconds = 5.0;
dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
[grayView removeFromSuperview];
});

Answer 3

- (void)showBanner {
UIView *newView = [[UIView alloc] initWithFrame:self.view.bounds];
newView.backgroundColor = [UIColor grayColor];
[self.view addSubview:newView];
[newView performSelector:#selector(removeFromSuperView) withObject:nil afterDelay:5.0f];
}
Very preliminary, but should work