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## Using Text Fields A text field is a user interface element used to obtain user input through an application. A UITextField looks like this:  Important properties of a text field: * Displays placeholder text when there is no user input * Normal text * Autocorrection type * Keyboard type * Return key type * Clear button mode * Alignment * Delegate * * * ## Updating Attributes in XIB You can change the text field attributes in the Attribute Inspector within the Utility area (the right side of the window) of the XIB file.  * * * ## Text Field Delegate We can set the delegate by right-clicking the UIElement in Interface Builder and connecting it to the File's Owner, as shown below:  Steps to use the delegate: * 1. Set the delegate as shown in the image above. * 2. Add the delegate to your response class. * 3. Implement the text field delegate methods. Important text field delegate methods are: - (void)textFieldDidBeginEditing:(UITextField *)textField - (void)textFieldDidEndEditing:(UITextField *)textField * 4. As their names imply, the two delegate methods above are called when editing begins and ends in the text field, respectively. * 5. For other delegate methods, please refer to the UITextDelegate Protocol reference manual. * * * ## Example Below, we use a simple example to create UI elements. The ViewController class will adopt the UITextFieldDelegate protocol. Modify the ViewController.h file as follows: Add the method `addTextField` to our ViewController.m file. Then call this method in the `viewDidLoad` method. Update `viewDidLoad` in ViewController.m as follows: ```objective-c #import "ViewController.h" @interface ViewController () @end @implementation ViewController - (void)viewDidLoad { ; //The custom method to create our textfield is called ; // Do any additional setup after loading the view, typically from a nib. } - (void)didReceiveMemoryWarning { ; // Dispose of any resources that can be recreated. } -(void)addTextField{ // This allocates a label UILabel *prefixLabel = [initWithFrame:CGRectZero]; //This sets the label text prefixLabel.text =@"## "; // This sets the font for the label [prefixLabel setFont:[UIFont boldSystemFontOfSize:14]]; // This fits the frame to size of the text ; // This allocates the textfield and sets its frame UITextField *textField = [ initWithFrame: CGRectMake(20, 50, 280, 30)]; // This sets the border style of the text field textField.borderStyle = UITextBorderStyleRoundedRect; textField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter; [textField setFont:[UIFont boldSystemFontOfSize:12]]; //Placeholder text is displayed when no text is typed textField.placeholder = @"Simple Text field"; //Prefix label is set as left view and the text starts after that textField.leftView = prefixLabel; //It set when the left prefixLabel to be displayed textField.leftViewMode = UITextFieldViewModeAlways; // Adds the textField to the view. [self.view addSubview:textField]; // sets the delegate to the current class textField.delegate = self; } // pragma mark is used for easy access of code in Xcode #pragma mark - TextField Delegates // This method is called once we click inside the textField -(void)textFieldDidBeginEditing:(UITextField *)textField{ NSLog(@"Text field did begin editing"); } // This method is called once we complete editing -(void)textFieldDidEndEditing:(UITextField *)textField{ NSLog(@"Text field ended editing"); } // This method enables or disables the processing of return key -(BOOL) textFieldShouldReturn:(UITextField *)textField{ ; return YES; } - (void)viewDidUnload { label = nil; ; } @end Running the application will produce the following output:  The delegate methods are called based on user actions. To know when the delegate is called, please refer to the console output.