Populate data in textfield from button action of another class - ios

Question

my problem is that i have a textfield on my viewcontroller which should be get filled by user and to provide options to fill the textfiled there is a arrow button front of textfield. Clicking on it open a new viewcontroller with a list of options. So when the user click on any option from that viewcontroller the data will automatically fill in that textfield and user return on previous viewcontroller. And i can not use preprefor segue in it so please provide an answer. If i am missing something let me know i ll comment or edit.

Answer 1

You can use NSNotificationCenter to fill back your UITextField. Add Observer to your first viewController class where you want to fill the textField. Add this lines of code in viewDidLoad-
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(fillMyTextField:) name:#"fillMyTextField" object:nil];
than add selector method in same class--
- (void)fillMyTextField:(NSNotification *)notification
{
self.myTxtField.text = (NSString *)notification.userInfo;
}
Now in your other viewController class where you select data for textField. Write the below code in method where you select your data like-
- (IBAction)selectDataAndBackToPreviosVC:(UIButton*)selectedOptionBtn {
id object=[NSString stringWithFormat:#"%#",selectedOptionBtn.titleLabel.text];
[[NSNotificationCenter defaultCenter] postNotificationName:#"fillTextField" object:nil userInfo:object];
[self.navigationController popViewControllerAnimated:YES];
}
in this I have used navigationViewController which use Push and Pop viewControllers and i have some UIButton in option selection viewController. I'm passing button title which is options to myTextField on IBAction.

Answer 2

In class where textfield Define Below method (add notification observer)
in viewDidLoad
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(fillTextField:)
name:#"fillTextField"
object:nil];
- (IBAction)fillTextField:(NSNotification *)sender
{
textField.text = (NSString *)notification.object
}
In Another class where u select date set below method in date selection action
[[NSNotificationCenter defaultCenter] postNotificationName:#"fillTextField" object:nil userInfo:textFieldInfo];

Answer 3

You can use NSNotification:
In View controller ofTextField add this
- (void) viewDidLoad
{
//Your rest of code then below statement
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(receiveTextNotification:)
name:#"TestNotification"
object:nil];
}
- (void)receiveTextNotification:(NSNotification *)notification {
NSLog(#"%# updated", [notification userInfo]);
}
- (void) dealloc
{
// If you don't remove yourself as an observer, the Notification Center
// will continue to try and send notification objects to the deallocated
// object.
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
In View controller of Button, on button click add this:
- (IBAction)fillTextFieldAction: (id) sender {
// All instances observing the `TestNotification` will be notified
[[NSNotificationCenter defaultCenter] postNotificationName:#"TestNotification" object:self userInfo:text]; //Object here can be any changed value .
}

Answer 4

[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(fillTextFieldAction:) name:#"fillTextField" object:nil];
- (IBAction)fillTextFieldAction:(NSNotification *)notification
{
textField.text = (NSString *)notification.object
}
[[NSNotificationCenter defaultCenter] postNotificationName:#"fillTextField" object:nil userInfo:textFieldInfo];