Resign the keyboard no matter where it is in the application. (I usually wrap my utility methods in a C function)

gistfile1.m

void globalResignKeyboard(void){
  
    UIWindow * window = [[UIApplication sharedApplication] keyWindow];
    for (UIView * view in [window subviews]){
        resignKeyboardInSubviewsOfView(view);
    }
}

void resignKeyboardInSubviewsOfView(UIView* view){
   
    if ([view respondsToSelector:@selector(resignFirstResponder)]){
        [view resignFirstResponder];
    }
    for (UIView * subview in [view subviews]){
        resignKeyboardInSubviewsOfView(subview);
    }
}