How to add delay between viewwillappear and viewdidappear in custom navigation?

Question

There is a delay between viewwillappear and viewdidappear when a view controller pushed to a navigation controller. Viewwillappear will be called immediatally, while viewdidappear will be called after the transation animation finished.

I want to make a custom navigation. Viewcontroller A is a container viewcontroller. It will contain viewcontroller B or viewcontroller C. At first, viewcontroller contains viewcontroller B(A is B's parent controller). Then controller B will navigate to controller C with a transation.

But viewdidappear will be called immediatally after viewwillappear, when addsubview is called. How to add delay between viewwillappear and viewdidappear? I hope viewwillappear will be called before the animation, and viewdidappear will be called after the animation. Can you help me?

There is a button in viewcontroller B's view. When tap the button, it will navigate to controller C. It looks like pushviewcontroller. The diffrence is, viewcontroller B will be dealloced. — Zhang Jiuzhou, Jul 06 '15 at 07:42
I do not want to use navigationcontroller and pushviewcontrller, because there is a lot of viewcontrollers(viewcontroller D, viewcontroller E...), I do not want leave them in the memory when they are not shown. — Zhang Jiuzhou, Jul 06 '15 at 07:44

score 0 · Answer 1 · answered Jul 06 '15 at 08:08

There is a good way to manually delay, try to put this in the bottom of viewwillappear

double delayInSeconds = 2.0;
dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
  NSLog(@"Do some work");
});

Hope this could help.

score 0 · Accepted Answer · answered Jul 06 '15 at 08:13

How about this way?

There is only one container - view controller A.
B, C, D... are all subviews instead of view controllers.
First, view controller A has view B by default.
And then click button in view B.
Do the animation for C and then in the completion block hide B or delete B.

Hopes this is helpful.

How to add delay between viewwillappear and viewdidappear in custom navigation?

2 Answers2