iOS 7 viewDidLoad executes slowly while pushing viewcontroller

iOS 7 viewDidLoad executes slowly while pushing viewcontroller

I was trying to push a viewcontroller B into navigation controller from A
and then assigning some properties of B in A. In this case, assigning of
properties was done and then viewDidLoad of viewcontroller A was executed.
Here, assigning properties in A should be done only after viewDidLoad of A
has done. For example,
[b.navController pushViewController:a animated:YES]; a.status = @"loaded";
Here status was assigned first and then viewDidLoad of A was executed.
This happens only in iOS 7 where as in iOS6 it works fine.
Can any one please let me know where was the problem?
Thank you.