prepareForSegue for TabBarController - ios

Question

I'm trying to pass data from my ViewController to TabBarController by using Objective-C. I'm trying to assign some data to "bottomTabEventList" (which is a property of my custom TabBarController class). Unfortunately, my program crashes by giving unrecognized selector instance error/warning.
In custom header of TabBarController class, named BottomTabview:
#interface BottomTabView : UITabBarController <UITabBarControllerDelegate>
#property(strong,nonatomic)EventList *bottomTabEventList;
#end
And prepareForSegue method in ViewController.m
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
BottomTabView *btw = [segue destinationViewController];
//checking
if(btw == nil)
NSLog(#"btw in viewController is nil");
else
NSLog(#"btw in viewController is NOT nil");
if(self.eventList.eventList == nil)
NSLog(#"eventList in viewController is nil");
else
NSLog(#"eventList in viewController is NOT nil"); //end of checking
btw.bottomTabEventList = self.eventList; //This is where crash appears
}
Exact crash log is:
-[ViewController setBottomTabEventList:]: unrecognized selector sent to instance 0x7fe923c6ba00
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[ViewController setBottomTabEventList:]: unrecognized selector sent to instance 0x7fe923c6ba00'
Segue is from ViewController to BottomTabView and its type is "Present Modally". I'd really appreciate if you can help/guide me. Thanks in advance.

Answer 1

The problem seems to be that btw is not actually of type BottomTabView and is just a UIViewController hence the crash log giving:
[ViewController setBottomTabEventList:]: unrecognized selector sent to instance
As UIViewController does't know what BottomTabEventList is.
You need to make sure that btw is actually a BottomTabView instance.
Do a little introspection and I bet it will not go into this statement:
if ([btw isKindOfClass:[BottomTabView class]]){
btw.bottomTabEventList = self.eventList;
}