Right bar button item not show without first time - ios

Question

This is first time, edit button visible. But when i come from another tab edit button not visible, but if i press there it will visible. In my UITableView i use a rightBarButton Edit item in UINavigationBar. But it show's only first time. When I come from another tab to this tab next time, it's not shown. If i press in that place of that button it become shown. What is the problem?
self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:#"Edit" style:UIBarButtonItemStylePlain target:self action:#selector(editActionOfTable) ];
-(void)editActionOfTable{
if (isEdited) {
isSelctedAll = NO;
[self.selectallButton setTitle:#"Select All" forState:UIControlStateNormal];
self.navigationItem.rightBarButtonItem.title = #"Edit";
//[self.editButton setTitle:#"Edit" forState:UIControlStateNormal];
[self.tableView setEditing:NO animated:YES];
[self customViewHide:YES];
isEdited = NO;
isDeleteButtonPress = false;
self.navigationItem.hidesBackButton = NO;
flagForCustomCell = false;
NSDictionary *userInfo = [NSDictionary dictionaryWithObject:#"bottom" forKey:#"pos_Key"];
[[NSNotificationCenter defaultCenter] postNotificationName: #"ad_banner" object:nil userInfo:userInfo];
}
else{
NSDictionary *userInfo = [NSDictionary dictionaryWithObject:#"top_of_tab" forKey:#"pos_Key"];
[[NSNotificationCenter defaultCenter] postNotificationName: #"ad_banner" object:nil userInfo:userInfo];
flagForCustomCell = true;
//disable delete button when array empty
[self.deleteButtonOutlet setEnabled:NO];
self.deleteButtonOutlet.alpha = 0.5;
//disable fav button when array empty
[self.favInHistoryOutlet setEnabled:NO];
self.favInHistoryOutlet.alpha = 0.5;
self.navigationItem.rightBarButtonItem.title = #"Done";
//[self.editButton setTitle:#"Done" forState:UIControlStateNormal];
[self customViewHide:NO];
isDeleteButtonPress = true;
[self.tableView setEditing:YES animated:YES];
self.navigationItem.hidesBackButton = YES;
isEdited = YES;
}
}
This is my ViewWillAppear code:
-(void)viewWillAppear:(BOOL)animated{
self.navigationItem.rightBarButtonItem.tintColor = [UIColor whiteColor];
NSManagedObjectContext *managedObjectContext = [self managedObjectContext];
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] initWithEntityName:#"History"];
self.devices = [[managedObjectContext executeFetchRequest:fetchRequest error:nil] mutableCopy];
self.devices=[[[self.devices reverseObjectEnumerator] allObjects] mutableCopy];
NSFetchRequest *fetchRequest1 = [[NSFetchRequest alloc] initWithEntityName:#"Favourite"];
self.fvrt = [[managedObjectContext executeFetchRequest:fetchRequest1 error:nil] mutableCopy];
self.fvrt=[[[self.fvrt reverseObjectEnumerator] allObjects] mutableCopy];
[self setHeightForSpecificRow];
isDeleteButtonPress = false;
if(self.segmentControl.selectedSegmentIndex == 0){
segment = self.devices.count;
if(segment == 0){
self.navigationItem.rightBarButtonItem.enabled = NO;
self.tableView.hidden = YES;
emptyView.hidden = NO;
if(IS_DEVICE_IPAD){
[noHistoryFavImage setImage:[UIImage imageNamed:#"no-history-ipad.png"]];
}
else{
[noHistoryFavImage setImage:[UIImage imageNamed:#"no-history-iphone.png"]];
}
emptyViewLabel1.text = #"You do not have any translation history right now.";
}
else{
self.navigationItem.rightBarButtonItem.enabled = YES;
self.tableView.hidden = NO;
emptyView.hidden = YES;
}
}
else{
segment = self.fvrt.count;
if(segment == 0){
self.navigationItem.rightBarButtonItem.enabled = NO;
self.tableView.hidden = YES;
emptyView.hidden = NO;
if(IS_DEVICE_IPAD){
[noHistoryFavImage setImage:[UIImage imageNamed:#"heart-ipad.png"]];
}
else{
[noHistoryFavImage setImage:[UIImage imageNamed:#"heart-iphone.png"]];
}
emptyViewLabel1.text = #"You do not have any favorites right now.";
}
else{
self.navigationItem.rightBarButtonItem.enabled = YES;
self.tableView.hidden = NO;
emptyView.hidden = YES;
}
}
[self.tableView reloadData];
//self.navigationController.navigationBar.tintColor = [UIColor redColor];
}