How to disable MasterView when the keyboard appears in the DetailView - xcode

Question

I would like to know if it's possible (and how) when the keyboard appears in the DetailView, to disable any MasterView controls until it disappears. All of this happens in a split view based app of course.
---Update for Prince's solution---
MasterViewController.h
#property (strong, nonatomic) UIView *MasterView;
MasterViewController.m
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
MasterView=self.view;
self.detailViewController = (DetailViewController *)[[self.splitViewController.viewControllers lastObject] topViewController];
self.detailViewController = (DetailViewController *)[[self.splitViewController.viewControllers lastObject] topViewController];
}
DetailViewController.m
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField
{
((MasterViewController *)self.parentViewController).MasterView.userInteractionEnabled=NO;
return YES;
}
This code as is, crashes the app with an "Unknown Selector" error.
How do i bind delegates; Don't know if that's the problem or not. Any help?

Answer 1

Use UITextField's delegate and also bind delegates:
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField
{
MasterView.userInteractionEnabled = NO;
.......
return YES;
}
- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
MasterView.userInteractionEnabled = YES;
[textField resignFirstResponder];
return YES;
}

Answer 2

I found out a solution!
in MasterView viewDidLoad:
//---registers the notifications for keyboard---
// to see if keyboard is shown / not shown
[[NSNotificationCenter defaultCenter]
addObserver: self
selector:#selector(keyboardDidShow:)
name:UIKeyboardDidShowNotification
object:self.view.window];
[[NSNotificationCenter defaultCenter]
addObserver:self
selector:#selector(keyboardDidHide:)
name:UIKeyboardDidHideNotification
object:nil];
and then...:
//----------Handling Keyboard Appearence---
-(void) keyboardDidShow:(NSNotification *) notification {
[self.tableView setUserInteractionEnabled:NO];
}
//---when the keyboard disappears---
-(void) keyboardDidHide:(NSNotification *) notification {
[self.tableView setUserInteractionEnabled:YES];
}
//---before the View window disappear---
-(void) viewWillDisappear:(BOOL)animated {
//---removes the notifications for keyboard---
[[NSNotificationCenter defaultCenter]
removeObserver: self
name:UIKeyboardWillShowNotification
object:nil];
[[NSNotificationCenter defaultCenter]
removeObserver:self
name:UIKeyboardWillHideNotification
object:nil];
}