Using Xcode, create a new View-based Application project and name it UsingViews.

In the UsingViewsViewController.m file, add the following code that appears in bold to the viewDidLoad method:

- (void)viewDidLoad {

    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Hello"
                             message:@"This is an alert view"
                             delegate:self
                             cancelButtonTitle:@"OK"
                             otherButtonTitles:nil];
    [alert show];
    [alert release];
    [super viewDidLoad];

}

Press Command-R to test the application on the iPhone Simulator. When the application is loaded, you see the alert view as shown in Figure 4-2.

Figure 4.2. Figure 4-2

Back in Xcode, modify the otherButtonTitles parameter by setting it with the value shown in bold:

UIAlertView *alert = [[UIAlertView alloc]
                         initWithTitle:@"Hello"
                         message:@"This is an alert view"
                         delegate:self
                         cancelButtonTitle:@"OK"
                         otherButtonTitles:@"Option 1",
                         @"Option 2", nil];

In the UsingViewsViewController.h file, add the following line that appears in bold:

#import <UIKit/UIKit.h>

@interface UsingViewsViewController : UIViewController
    <UIAlertViewDelegate> {

}

@end

In the UsingViewsViewController.m file, add the following method:

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:
    (NSInteger)buttonIndex {

    NSLog([NSString stringWithFormat:@"%d", buttonIndex]);

}

Press Command-R to test the application in the iPhone Simulator. Notice that there are now two additional buttons besides the OK button (see Figure 4-3).

Figure 4.3. Figure 4-3

Click any one of the buttons — Option 1, Option 2, or OK.

In Xcode, press Command-Shift-R to view the Debugger Console window. Observe the values printed. You can rerun the application a number of times and click the different buttons to observe the values printed.

You should observe the values printed for each button clicked:

Using the same project created in the previous section, modify the viewDidLoad method (in the UsingViewsViewController.m file) as follows:

- (void)viewDidLoad {

    UIActionSheet *action = [[UIActionSheet alloc]
                            initWithTitle:@"Title of Action Sheet"
                            delegate:self
                            cancelButtonTitle:@"OK"
                            destructiveButtonTitle:@"Delete Message"
                            otherButtonTitles:@"Option 1", @"Option 2", nil];
    [action showInView:self.view];
    [action release];
    [super viewDidLoad];

}

In the UsingViewsViewController.h file, add the following statement that appears in bold:

#import <UIKit/UIKit.h>

@interface UsingViewsViewController : UIViewController
    <UIActionSheetDelegate> {

}

@end

In the UsingViewsViewController.m file, add the following statement that appears in bold:

- (void)actionSheet:(UIActionSheet *)actionSheet
clickedButtonAtIndex:(NSInteger)buttonIndex{

    NSLog([NSString stringWithFormat:@"%d", buttonIndex]);

}

Press Command-R to test the application using the iPhone Simulator. Figure 4-4 shows the action sheet in action.

Figure 4.4. Figure 4-4

Click any one of the buttons: Delete Message, Option 1, Option 2, or OK.

In Xcode, press Command-Shift-R to view the Debugger Console window. Observe the values printed. You can rerun the application a number of times and click the different buttons to observe the values printed.

You should observe the values that printed for each button clicked:

Using the same project created in the previous two sections, add five images to the Resources folder by dragging and dropping them from the Finder. Figure 4-6 shows the five images added to the project.

Double-click the UsingViewsViewController.xib file to edit it using Interface Builder.

Drag and drop two ImageView views onto the View window. (see Figure 4-7). At this point, overlap them (but not entirely) as shown in the figure.

Figure 4.6. Figure 4-6

Figure 4.7. Figure 4-7

With one of the ImageView views selected, open the Attributes Inspector window and set the Tag property to 0. Select the second ImageView and set the Tag property to 1 (see Figure 4-8).

Figure 4.8. Figure 4-8

Drag and drop the Page Control view onto the View window and set its number of pages to five (see Figure 4-9).

Figure 4.9. Figure 4-9

Back in Xcode, in the UsingViewsViewController.h file, define three outlets and two UIImageView objects:

#import <UIKit/UIKit.h>

@interface UsingViewsViewController : UIViewController {
    IBOutlet UIPageControl *pageControl;
    IBOutlet UIImageView *imageView1;
    IBOutlet UIImageView *imageView2;

    UIImageView *tempImageView, *bgImageView;
}

@property (nonatomic, retain) UIPageControl *pageControl;
@property (nonatomic, retain) UIImageView *imageView1;
@property (nonatomic, retain) UIImageView *imageView2;

@end

In Interface Builder, connect the three outlets to the views on the View window. Figure 4-10 shows the connections made for the imageView1, imageView2, and pageControl outlets.

Figure 4.10. Figure 4-10

You can now rearrange the ImageView views on the View window so that they overlap each other.

In Xcode, add the following statements that appear in bold to the UsingViewsViewController.m file:

#import "UsingViewsViewController.h"

@implementation UsingViewsViewController

@synthesize pageControl;
@synthesize imageView1, imageView2;

- (void)viewDidLoad {

    //---initialize the first imageview to display an image---
    [imageView1 setImage:[UIImage imageNamed:@"iMac_old.jpeg"]];
    tempImageView = imageView2;

    //---make the first imageview visible and hide the second---
    [imageView1 setHidden:NO];
    [imageView2 setHidden:YES];

    //---add the event handler for the page control---
    [pageControl addTarget:self action:@selector(pageTurning:)
        forControlEvents:UIControlEventValueChanged];

[super viewDidLoad];

}

//---when the page control's value is changed---
- (void) pageTurning: (UIPageControl *) pageController
{
    //---get the page number you can turning to---
    NSInteger nextPage = [pageController currentPage];
    switch (nextPage) {
        case 0:
            [tempImageView setImage:[UIImage imageNamed:@"iMac_old.jpeg"]];
            break;
        case 1:
            [tempImageView setImage:[UIImage imageNamed:@"iMac.jpeg"]];
            break;
        case 2:
            [tempImageView setImage:[UIImage imageNamed:@"Mac8100.jpeg"]];
            break;
        case 3:
            [tempImageView setImage:[UIImage imageNamed:@"MacPlus.jpeg"]];
            break;
        case 4:
            [tempImageView setImage:[UIImage imageNamed:@"MacSE.jpeg"]];
            break;
        default:
            break;
    }

    //---switch the two imageview views---
    if (tempImageView.tag==0) { //---imageView1---
        tempImageView = imageView2;
        bgImageView = imageView1;
    }
    else {    //---imageView2---
        tempImageView = imageView1;
        bgImageView = imageView2;
    }

    //---animate the two views flipping---
    [UIView beginAnimations:@"flipping view" context:nil];
    [UIView setAnimationDuration:0.5];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
    [UIView setAnimationTransition: UIViewAnimationTransitionFlipFromLeft
        forView:tempImageView cache:YES];
    [tempImageView setHidden:YES];
    [UIView commitAnimations];

    [UIView beginAnimations:@"flipping view" context:nil];
    [UIView setAnimationDuration:0.5];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
    [UIView setAnimationTransition: UIViewAnimationTransitionFlipFromRight
        forView:bgImageView cache:YES];
    [bgImageView setHidden:NO];

[UIView commitAnimations];

}

- (void)dealloc {
    [pageControl release];
    [imageView1 release];
    [imageView2 release];
    [super dealloc];
}

- (void)didReceiveMemoryWarning {
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];
}

- (void)viewDidUnload {
}

@end

Press Command-R to test the application on the iPhone Simulator. When you tap the Page Control located at the bottom of the screen, the image view flips to display the next one (see Figure 4-11).

Figure 4.11. Figure 4-11

Using Xcode, create a new View-based Application project and name it UsingViews2.

Double-click the UsingViews2ViewController.xib file to edit it using Interface Builder.

Add the following views to the View window (see Figure 4-12):

Figure 4.12. Figure 4-12

Add another View (from the Library) onto the View window and then add a Label view to it (see Figure 4-13). Be careful when you position the second view — make sure that the second view is not contained within the first view. This is because when you use the mouse and drag the second View over the first, Interface Builder will think that you are trying to make the second View a child of the first View. To prevent this from happening, use the cursor to move the second view over the first. The View window should now look like Figure 4-13.

Figure 4.13. Figure 4-13

You can verify that the two Views are at the same level by viewing the UsingViews2ViewController.xib window in List mode (see Figure 4-14).

Figure 4.14. Figure 4-14

In the UsingViews2ViewController.h file, declare the following outlets:

#import <UIKit/UIKit.h>

@interface UsingViews2ViewController : UIViewController {
    IBOutlet UIView *view1;
    IBOutlet UIView *view2;
    IBOutlet UISegmentedControl *segmentedControl;
}

@property (nonatomic, retain) UIView *view1;
@property (nonatomic, retain) UIView *view2;
@property (nonatomic, retain) UISegmentedControl *segmentedControl;

@end

Back in Interface Builder, connect the outlets to the respective views in the View window. (You may have to move the two Views so that you can connect the two UIView outlets to them.)

In Xcode, add the following statements that appear in bold to the UsingViews2ViewController.h file:

#import "UsingViews2ViewController.h"

@implementation UsingViews2ViewController
@synthesize segmentedControl;
@synthesize view1, view2;

- (void)viewDidLoad {
    //---add the event handler for the segmented control---
    [segmentedControl addTarget:self action:@selector(segmentChanged:)
    forControlEvents:UIControlEventValueChanged];

    [super viewDidLoad];
}

//---when the segment has changed---
- (IBAction)segmentChanged:(id)sender {
    NSInteger selectedSegment = segmentedControl.selectedSegmentIndex;
    if (selectedSegment == 0) {
        //---toggle the correct view to be visible---
        [self.view1 setHidden:NO];
        [self.view2 setHidden:YES];
    }
    else{
        //---toggle the correct view to be visible---
        [self.view1 setHidden:YES];
        [self.view2 setHidden:NO];
    }
}

- (void)dealloc {
    [segmentedControl release];
    [view1 release];
    [view2 release];
    [super dealloc];
}

Press Command-R to test the application on the iPhone Simulator.

When you tap the First segment, the First View label appears. When you tap the Second segment, you see the Second View label (see Figure 4-15).

Figure 4.15. Figure 4-15

Using Xcode, create a new View-based Application project and name it UsingViews3.

Double-click the UsingViews3ViewController.xib file to edit it using Interface Builder.

In the View window, add a Web view from the Library (see Figure 4-16). In the Attributes Inspector window for the Web view, check the Scales Page to Fit property.

Figure 4.16. Figure 4-16

In the UsingViews3ViewController.h file, declare an outlet for the Web view:

#import <UIKit/UIKit.h>

@interface UsingViews3ViewController : UIViewController {
    IBOutlet UIWebView *webView;
}

@property (nonatomic, retain) UIWebView *webView;

@end

Back in Interface Builder, connect the webView outlet to the Web view.

In the UsingViews3ViewController.m file, add the following statements that appear in bold:

#import "UsingViews3ViewController.h"

@implementation UsingViews3ViewController

@synthesize webView;

- (void)viewDidLoad {

    NSURL *url = [NSURL URLWithString:@"http://www.apple.com"];
    NSURLRequest *req = [NSURLRequest requestWithURL:url];
    [webView loadRequest:req];

    [super viewDidLoad];
}

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

Press Command-R to test the application on the iPhone Simulator. You should see the application loading the page from Apple.com (see Figure 4-17).

Figure 4.17. Figure 4-17

In the VCExampleViewController.m, add the following lines of code that appear in bold:

-(IBAction) displayView:(id) sender{
secondViewController = [[SecondViewController alloc]
    initWithNibName:@"SecondView" bundle:nil];

    [UIView beginAnimations:@"flipping view" context:nil];
    [UIView setAnimationDuration:1];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
    [UIView setAnimationTransition: UIViewAnimationTransitionCurlDown
        forView:self.view cache:YES];

    [self.view addSubview:secondViewController.view];

    [UIView commitAnimations];
}

Press Command-R to test the application. Observe what happens when the Display SecondView button is clicked (see Figure 4-30).

Figure 4.30. Figure 4-30

Back in Xcode, add the following lines that appear in bold to the SecondViewController.m file:

-(IBAction) btnReturn:(id) sender {

    [UIView beginAnimations:@"flipping view" context:nil];
    [UIView setAnimationDuration:1];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseIn];
    [UIView setAnimationTransition:
       UIViewAnimationTransitionCurlUp
       forView:self.view.superview cache:YES];

    [self.view removeFromSuperview];

    [UIView commitAnimations];

}

Press Command-R to test the application. Notice that when you now press the Return button in the second view, the second view flips up (see Figure 4-31).

Figure 4.31. Figure 4-31

Double-click the VCExampleViewController.xib file and add a DatePicker view to the View window (see Figure 4-32).

Figure 4.32. Figure 4-32

In the VCExampleViewController.h file, create an outlet for this DatePicker view and then expose it as a property:

#import <UIKit/UIKit.h>

@interface VCExampleViewController : UIViewController {
    //---outlet for the DatePicker view---
    IBOutlet UIDatePicker *datePicker;
}

//---expose this outlet as a property---
@property (nonatomic, retain) UIDatePicker *datePicker;

-(IBAction) displayView:(id) sender;

@end

In the VCExampleViewController.xib window, Control-click and drag the File's Owner Item to the DatePicker view and then select datePicker.

In the SecondViewController.h, create an object of type UIDatePicker and then expose it as a property:

#import <UIKit/UIKit.h>

@interface SecondViewController : UIViewController {
   //---object of type UIDatePicker---
   UIDatePicker *selectedDatePicker;
}

//---expose the object as a property---
@property (nonatomic, retain) UIDatePicker *selectedDatePicker;

-(IBAction) btnReturn:(id) sender;

@end

In the SecondViewController.m file, add the following lines that appear in bold to the viewDidLoad method:

#import "SecondViewController.h"

@implementation SecondViewController
@synthesize selectedDatePicker;

- (void)viewDidLoad {

//---display the date and time selected in the previous view---
    NSDateFormatter *formatter = [[[NSDateFormatter alloc] init] autorelease];
    [formatter setDateFormat:@"MMM dd, yyyy HH:mm"];

    UIAlertView *alert = [[UIAlertView alloc]
                             initWithTitle:@"Date and time selected"
                             message:[formatter
                                 stringFromDate:selectedDatePicker.date]
                             delegate:self
                             cancelButtonTitle:@"OK"
                             otherButtonTitles:nil];
    [alert show];
    [alert release];
    [super viewDidLoad];
}

- (void)dealloc {
    //---release the memory used by the property---
    [selectedDatePicker release];
    [super dealloc];
}

Finally, in the VCExampleViewController.m file, add the following lines that appear in bold:

#import "VCExampleViewController.h"
#import "SecondViewController.h"

@implementation VCExampleViewController
@synthesize datePicker;
SecondViewController *secondViewController;

-(IBAction) displayView:(id) sender{
    secondViewController = [[SecondViewController alloc]
        initWithNibName:@"SecondView" bundle:nil];

    //---set the property of the second view with the DatePicker view in
    // the current view---
    secondViewController.selectedDatePicker = datePicker;

    [UIView beginAnimations:@"flipping view" context:nil];
    [UIView setAnimationDuration:1];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
    [UIView setAnimationTransition: UIViewAnimationTransitionCurlDown
     forView:self.view cache:YES];

    [self.view addSubview:secondViewController.view];

    [UIView commitAnimations];

}

Press Command-R to test the application on the iPhone Simulator. Select a date and time in the DatePicker view and press the Display SecondView button. The selected date and time are displayed when the second view is displayed (see Figure 4-33).

Figure 4.33. Figure 4-33