Using Xcode, create a new Tab Bar application project and name it TabBarApplication.

Examine the content of the project (see Figure 8-3). Besides the usual application delegate files, it also contains a View Controller (FirstViewController) and two XIB files: MainWindow.xib and SecondView.xib.

Figure 8.3. Figure 8-3

Examine the content of the TabBarApplicationAppDelegate.h file, which is as follows:

#import <UIKit/UIKit.h>
@interface TabBarApplicationAppDelegate : NSObject
    <UIApplicationDelegate, UITabBarControllerDelegate> {
    UIWindow *window;
    UITabBarController *tabBarController;
}

@property (nonatomic, retain) IBOutlet UIWindow *window;
@property (nonatomic, retain) IBOutlet UITabBarController *tabBarController;

@end

Note that instead of the usual UIViewController class, you are now using the UITabBarController class, which inherits from the UIViewController class. A TabBarController is a specialized UIViewController class that contains a collection of view controllers.

When the application has finished loading, the current view of the UITabBarController instance is loaded, an occurrence that is evident in the TabBarApplicationAppDelegate.m file:

import "TabBarApplicationAppDelegate.h"

@implementation TabBarApplicationAppDelegate

@synthesize window;
@synthesize tabBarController;

- (void)applicationDidFinishLaunching:(UIApplication *)application {

    // Add the tab bar controller's current view as a subview of the window
    [window addSubview:tabBarController.view];
}

Double-click the MainWindow.xib file to edit it in Interface Builder. Observe the two Tab Bar Item views contained within the Tab Bar view shown at the bottom of the View.

Click the first Tab Bar item labeled First (see Figure 8-4). In the Identify Inspector window, observe that this is a View Controller and that the implementing class is FirstViewController.

Figure 8.4. Figure 8-4

Click the second Tab Bar item and view its Identity Inspector window. Notice that it is pointing to the base UIViewController class. Now, view its Attributes Inspector window (see Figure 8-5). Notice that in this case, it is loading its View window from another NIB file — SecondView.

Figure 8.5. Figure 8-5

Back in Xcode, press Command-R to run the application on the iPhone Simulator (see Figure 8-6). You can now touch the Tab Bar items at the bottom of the screen to switch between the two views.

Figure 8.6. Figure 8-6

Using Xcode, create a Navigation-based Application project and name it NavApplication.

Observe the files created by the template (see Figure 8-18). As usual, there are the application delegate files, as well as a View Controller named RootViewController. There are two XIB files: RootViewController.xib and MainWindow.xib.

Figure 8.18. Figure 8-18

Examine the content of the NavAplicationAppDelegate.h file:

@interface NavApplicationAppDelegate : NSObject <UIApplicationDelegate> {

    UIWindow *window;
    UINavigationController *navigationController;
}

@property (nonatomic, retain) IBOutlet UIWindow *window;
@property (nonatomic, retain) IBOutlet UINavigationController
     *navigationController;

@end

Instead of using a generic View Controller, it is now using a UINavigationController class. The UINavigationController class is a specialized View Controller that manages the navigation of hierarchical content.

Examine the content of the NavAplicationAppDelegate.m file, in particular the applicationDidFinishLaunching: method:

#import "NavApplicationAppDelegate.h"
#import "RootViewController.h"

@implementation NavApplicationAppDelegate

@synthesize window;
@synthesize navigationController;

#pragma mark -
#pragma mark Application lifecycle

- (void)applicationDidFinishLaunching:(UIApplication *)application {

    // Override point for customization after app launch

    [window addSubview:[navigationController view]];
    [window makeKeyAndVisible];
}

Here, you are adding the view of the navigation controller to the current view to make it visible when the application is loaded.

Double-click the MainWindow.xib file to edit it in Interface Builder. Figure 8-19 shows that the MainWindow.xib window (shown in List View) contains a Navigation Controller item. The Navigation Controller item itself contains a Navigation Bar item as well as a View that is loaded from the RootViewController class.

Figure 8.19. Figure 8-19

Double-click the RootViewController.xib file to open it in Interface Builder. Observe that by default, the Navigation-Application template uses a Table view for the root View Controller (See Figure 8-20).

Figure 8.20. Figure 8-20

Press Command-R to test the application. By itself, the application doesn't show much; all you see are rows of lines (see Figure 8-21). You learn how to populate the Table view next.

Figure 8.21. Figure 8-21

In the RootViewController.m file, add the following statements highlighted in bold to declare and initialize an array containing a list of movies:

#import "RootViewController.h"

@implementation RootViewController

NSMutableArray *listOfMovies;

- (void)viewDidLoad {

      //---initialize the array---
      listOfMovies = [[NSMutableArray alloc] init];

      //---add items---
      [listOfMovies addObject:@"Training Day"];
      [listOfMovies addObject:@"Remember the Titans"];

[listOfMovies addObject:@"John Q."];
      [listOfMovies addObject:@"The Bone Collector"];
      [listOfMovies addObject:@"Ricochet"];
      [listOfMovies addObject:@"The Siege"];
      [listOfMovies addObject:@"Malcom X"];
      [listOfMovies addObject:@"Antwone Fisher"];
      [listOfMovies addObject:@"Courage Under Fire"];
      [listOfMovies addObject:@"He Got Game"];
      [listOfMovies addObject:@"The Pelican Brief"];
      [listOfMovies addObject:@"Glory"];
      [listOfMovies addObject:@"The Preacher's Wife"];

      //---set the title of the navigation bar---
      self.navigationItem.title = @"Movies";

    [super viewDidLoad];
}

- (void)dealloc {
    [listOfMovies release];
    [super dealloc];
}

Insert the following statement in bold in the tableview:numberOfRowsInSection: method to specify the number of rows to display for the Table view:

//---specify the number of rows in the table view---
- (NSInteger)tableView:(UITableView *)tableView
              numberOfRowsInSection:(NSInteger)section {

      //---set it to the number of items in the array---
      return [listOfMovies count];

}

Insert the following statements in bold in the tableview:cellForRowAtIndexPath: method to specify the appearance of each cell:

// Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView
                      cellForRowAtIndexPath:(NSIndexPath *)indexPath {

    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView
        dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
                                          reuseIdentifier:CellIdentifier]
                                          autorelease];

}

      NSString *cellValue = [listOfMovies objectAtIndex:indexPath.row];
      cell.textLabel.text = cellValue;

    return cell;
}

Save the project and press Command-R to test the application on the iPhone Simulator. Observe the list of movies shown in the table view (see Figure 8-22).

Figure 8.22. Figure 8-22