Double-click the MainView.xib file to edit it in Interface Builder.

In the MainView.xib window, double-click the Main View item to display the Main View window (see Figure 11-14). Add a Button view to it and label it as Load Settings Values.

Figure 11.14. Figure 11-14

Double-click the FlipsideView.xib file to edit it in Interface Builder.

In the FlipsideView.xib window, double-click the Flipside View item and add the following views to the Flipside View window (see Figure 11-15):

Back in Xcode, insert the following code that appears in bold into the

MainViewController.h file:

#import "FlipsideViewController.h"

@interface MainViewController : UIViewController <FlipsideViewControllerDelegate> {
}

- (IBAction)loadSettings: (id) sender;
- (IBAction)showInfo;

@end

In the FlipsideViewController.h file, insert the following code that appears in bold:

@protocol FlipsideViewControllerDelegate;

@interface FlipsideViewController : UIViewController
    <UIPickerViewDataSource, UIPickerViewDelegate> {
    id <FlipsideViewControllerDelegate> delegate;

    IBOutlet UITextField *loginName;
    IBOutlet UITextField *password;
    IBOutlet UIPickerView *favoriteColor;

}
@property (nonatomic, retain) UITextField *loginName;
@property (nonatomic, retain) UITextField *password;
@property (nonatomic, retain) UIPickerView *favoriteColor;

@property (nonatomic, assign) id <FlipsideViewControllerDelegate> delegate;
- (IBAction)done;

@end

@protocol FlipsideViewControllerDelegate
- (void)flipsideViewControllerDidFinish:(FlipsideViewController *)controller;
@end

In the FlipsideViewController.m file, add the following statements:

#import "FlipsideViewController.h"

@implementation FlipsideViewController

@synthesize delegate;
@synthesize loginName;
@synthesize password;
@synthesize favoriteColor;

In Interface Builder, connect the outlets and action to the various views. In the FlipsideView.xib window, do the following:

Right-click the File's Owner item to verify that all the connections are connected properly (see Figure 11-16).

Figure 11.16. Figure 11-16

In the MainView.xib window, Control-click and drag the Button view to the File's Owner item and select loadSettings:.

Save the project in Interface Builder.

In Xcode, add the following code in bold to the FlipsideViewController.m file:

#import "FlipsideViewController.h"

@implementation FlipsideViewController

@synthesize delegate;
@synthesize loginName;
@synthesize password;
@synthesize favoriteColor;

NSMutableArray *colors;
NSString *favoriteColorSelected;

- (void)viewDidLoad {
    //---create an array containing the colors values---
    colors = [[NSMutableArray alloc] init];
    [colors addObject:@"Red"];

[colors addObject:@"Green"];
    [colors addObject:@"Blue"];


    [super viewDidLoad];
    self.view.backgroundColor = [UIColor viewFlipsideBackgroundColor];
}

//---number of components in the Picker view---
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)thePickerView {
    return 1;
}

//---number of items(rows) in the Picker view---
- (NSInteger)pickerView:(UIPickerView *)thePickerView
    numberOfRowsInComponent:(NSInteger)component {
    return [colors count];
}

//---populating the Picker view---
- (NSString *)pickerView:(UIPickerView *)thePickerView titleForRow:(NSInteger)row
    forComponent:(NSInteger)component {
    return [colors objectAtIndex:row];
}

//---the item selected by the user---
- (void)pickerView:(UIPickerView *)thePickerView didSelectRow:(NSInteger)row
    inComponent:(NSInteger)component {
    favoriteColorSelected = [colors objectAtIndex:row];
}

- (void)dealloc {
    [colors release];
    [favoriteColorSelected release];
    [loginName release];
    [password release];
    [favoriteColor release];
    [super dealloc];
}

That's it! Press Command-R to test the application on the iPhone Simulator. Figure 11-17 shows the UI of the application for the Main and Flipside views.

Insert the following lines of code that appear in bold to the MainViewController.m file (make sure that the code line with password and favorite color markers is entered all on one line, unlike how it appears in the following code):

#import "MainViewController.h"
#import "MainView.h"

@implementation MainViewController

- (IBAction) loadSettings: (id) sender{

    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];

    NSString *strLoginname = [defaults objectForKey:@"login_name"];
    NSString *strPassword = [defaults objectForKey:@"password"];
    NSString *strColor = [defaults objectForKey:@"color"];

    NSString *str = [[NSString alloc] initWithFormat:@"Login name is "%@",
password is "%@", and favorite color is "%@"",
                     strLoginname, strPassword, strColor];

    UIAlertView *alert = [[UIAlertView alloc]
                          initWithTitle:@"Settings Values"
                          message:str
                          delegate:nil
                          cancelButtonTitle: @"Done"
                          otherButtonTitles:nil];
    [alert show];

    [strLoginname release];
    [strPassword release];
    [strColor release];
    [str release];
    [alert release];
}

Press Command-R to test the application on the iPhone Simulator. When the application is loaded, tap on the Load Settings Values button and you should see the settings values displayed in an alert view (see Figure 11-18).

Figure 11.18. Figure 11-18

In the FlipsideViewController.m file, insert the following code that appears in bold:

#import "FlipsideViewController.h"

@implementation FlipsideViewController

@synthesize delegate;
@synthesize loginName;
@synthesize password;
@synthesize favoriteColor;

NSMutableArray *colors;
NSString *favoriteColorSelected;

- (void)viewDidLoad {
    colors = [[NSMutableArray alloc] init];
    [colors addObject:@"Red"];
    [colors addObject:@"Green"];
    [colors addObject:@"Blue"];


    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    loginName.text = [defaults objectForKey:@"login_name"];
    password.text = [defaults objectForKey:@"password"];

    //---find the index of the array for the color saved---
    favoriteColorSelected = [[NSString alloc] initWithString:
                            [defaults objectForKey:@"color"]];
    int selIndex = [colors indexOfObject:favoriteColorSelected];

    //---display the saved color in the Picker view---
    [favoriteColor selectRow:selIndex inComponent:0 animated:YES];

    [super viewDidLoad];
    self.view.backgroundColor = [UIColor viewFlipsideBackgroundColor];
}

- (IBAction)done {

    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    [defaults setObject:loginName.text forKey:@"login_name"];

[defaults setObject:password.text forKey:@"password"];
    [defaults setObject:favoriteColorSelected forKey:@"color"];

    [self.delegate flipsideViewControllerDidFinish:self];
}

Press Command-R to test the application on the iPhone Simulator. When the application is loaded, tap the i icon to switch to the Flipside view. Make some changes to the login name, password, and favorite color (see Figure 11-20). When you press Done, all the changes are made to the phone. When you return to the Main view, tapping the Load Settings Values button displays the updated settings values.

Figure 11.20. Figure 11-20