Question

My Header file

MyClass.h
@interface MyClass : UIViewController<UITextFieldDelegate>
{
}
@property (retain, nonatomic) IBOutlet UITextField *customValue;

MyClass.m

- (void)viewDidLoad
{
    customValue.delegate=self;
}
- (void)textFieldDidBeginEditing:(UITextField *)customValue
{
    NSLog(@"custom tips value %@",customValue.text);
}

My NSLog is printing the message, but the customValue.text is not being displayed and is coming as null.

EDIT 1
I need to get the values that is entered in the textfiled as and when the user is enter the value

Answer 1

textFieldDidBeginEditing as it name indicates , it will work when you start editing on the textField.

For accomplishing your requirement you need to use the shouldChangeCharactersInRange delegate method.

- (BOOL)textField:(UITextField *)e shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    NSString *substring = textField.text;
    substring = [substring stringByAppendingString:string];
    NSLog(@"Text : %@",substring);
    return YES;
}

textFieldDidBeginEditing:

Tells the delegate that editing began for the specified text field.

- (void)textFieldDidBeginEditing:(UITextField *)textField Parameters

textField

The text field for which an editing session began.

Discussion

This method notifies the delegate that the specified text field just
became the first responder. You can use this method to update your
delegate’s state information. For example, you might use this method
to show overlay views that should be visible while editing.

Implementation of this method by the delegate is optional.
Availability

Available in iOS 2.0 and later.

Declared In UITextField.h

textField:shouldChangeCharactersInRange:replacementString:

Asks the delegate if the specified text should be changed.

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string

Parameters

textField

The text field containing the text.

range

The range of characters to be replaced 

string

The replacement string. 

Return Value

YES if the specified text range should be replaced; otherwise, NO to
keep the old text. Discussion

The text field calls this method whenever the user types a new
character in the text field or deletes an existing character.
Availability

Available in iOS 2.0 and later.

Declared In UITextField.h

For more check UITextFieldDelegate