This slideshow introduces some basic suggestions and design patterns for creating a Universal application (iPhone and iPad) under iOS. Presented originally on September 29, 2010 at the Vancouver Island iOS Developers' Group.

1. Cliff McCollum
cliffmcc@gmail.com
www.leadingsoftware.ca
Universal iOS Applications
Some simple patterns and suggestions

2. Universal
Application?

3. Intended Audience
1. You understand Objective-C
2. You have created working iOS Apps before
3. You are familiar with the XCode environment
4. You have used Interface Builder
If this does not describe you, not to worry. As long as you
have a good understand of C++, Java, or another related
language you should be able to understand the examples.

4. Basic Steps
1. Configure Project Settings
2. Create Your Classes
3. Test
4. Configure Icons
5. Submit

5. Key Project Settings
Always use latest SDK...
...but target oldest OS
Project settings
Application .plist file

6. Key Project Settings
Weak-link new libraries.

7. Initial XIB file
Shared or separate App Delegate?
It’s up to you.

8. Coding Tools
CHECK CLASS SUPPORT
Class notificationClass = NSClassFromString(@"UILocalNotification");
if (notificationClass) {
UILocalNotification* n = [[notificationClass alloc] init];
}
CHECK METHOD SUPPORT
if ([UIApplication
instancesRespondToSelector:@selector(scheduleLocalNotification:)]) {
[[UIApplication sharedApplication] scheduleLocalNotification:n];
}
CHECK DEVICE
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
// This is a great new Macro in recent SDKs
}

9. Coding Tools
CHECK FOR RETINA DISPLAY
if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)] &&
[[UIScreen mainScreen] scale] == 2.0) {
// do iPhone 4 stuff
}

10. Common Patterns

11. 1. Common controller, different bundles.
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
self.infoViewController = [[InfoViewController alloc]
initWithNibName:@"InfoViewController_iPad" bundle:nil];
}
else {
self.infoViewController = [[InfoViewController alloc]
initWithNibName:@"InfoViewController_iPhone" bundle:nil];
}
iPhone iPad

12. 2. Common controller, unique presentation.
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
// On the iPad, present the view in a popup controller
self.notesViewController = [[NotesViewController alloc]
initWithNibName:@"CardNotes_iPad" bundle:nil];
CGSize popoverSize;
popoverSize.width = 600;
popoverSize.height = 325;
self.notesViewController.contentSizeForViewInPopover = popoverSize;
self.notesViewPopoverController = [[UIPopoverController alloc]
initWithContentViewController:self.notesViewController];
self.notesViewController.modalInPopover = TRUE;
CGRect cardTitleRect;
cardTitleRect.origin.x = 384;
cardTitleRect.origin.y = 180;
cardTitleRect.size.width = 1;
cardTitleRect.size.height = 1;
[self.notesViewPopoverController presentPopoverFromRect:cardTitleRect
inView:self.view permittedArrowDirections:UIPopoverArrowDirectionUp animated:TRUE];
}
else {
// iPhone actions
self.notesViewController = [[NotesViewController alloc]
initWithNibName:@"CardNotes_iPhone" bundle:nil];
[self presentModalViewController:self.notesViewController animated:TRUE];
}

13. 2. Common controller, unique presentation.

14. 2. Common controller, unique presentation.
-(void)notesViewCleanup {
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
{
[self.notesViewPopoverController dismissPopoverAnimated:TRUE];
[self.notesViewPopoverController release];
self.notesViewPopoverController = nil;
}
else {
[self dismissModalViewControllerAnimated:TRUE];
}
[self.notesViewController release];
}

15. 3. Common Navigation controller,
-(void)display {
unique presentation.
[self prepareDisplay];
[self.parentController presentModalViewController:self.navigationController animated:TRUE];
}
-(void)displayInPopup {
self.usingPopover = TRUE;
[self prepareDisplay];
CGSize popoverSize;
popoverSize.width = 300; popoverSize.height = 365;
self.navigationController.contentSizeForViewInPopover = popoverSize;
self.popoverController = [[UIPopoverController alloc]
initWithContentViewController:self.navigationController];
CGRect solutionTitleRect;
solutionTitleRect.origin.x = 384; solutionTitleRect.origin.y = 420;
solutionTitleRect.size.width = 1; solutionTitleRect.size.height = 1;
[self.popoverController presentPopoverFromRect:solutionTitleRect inView:self.parentController.view
permittedArrowDirections:UIPopoverArrowDirectionUp animated:TRUE];
}
-(void)prepareDisplay {
self.solutionTableController = [[SolutionSetTableController alloc]
initWithNibName:@"SolutionSetTable" bundle:nil];
self.solutionTableController.title = @"Select An Issue";
self.solutionTableController.delegate = self;
UINavigationController *newNav = [[UINavigationController alloc]
initWithRootViewController:self.solutionTableController];
UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithTitle:@"Back"
style:UIBarButtonItemStylePlain target:self action:@selector(backButtonClicked:)];
newNav.navigationBar.topItem.leftBarButtonItem = backButton;
[backButton release];
self.navigationController = newNav;
}

16. 3. Common Navigation controller,
unique presentation.

17. 3. Common Navigation controller,
unique presentation.
-(void)cleanupDisplay {
if (self.usingPopover) {
[self.popoverController dismissPopoverAnimated:TRUE];
}
else {
[self.navigationController dismissModalViewControllerAnimated:TRUE];
}
}

18. 4. UIWebView for unique presentation
@media only screen and (min-device-width: 768px) and (max-device-width: 1024px) {
/* rules for iPad */
body {
font-size: 24px;
}
img.LGautosize {
width: 36px; height: 36px;
}
img.SMautosize {
width: 24px; height: 24px;
}
}
@media only screen and (min-device-width: 320px) and (max-device-width: 480px) {
/* iPhone rules here */
body {
font-size: 16px;
}
img.LGautosize {
width: 24px; height: 24px;
}
img.SMautosize {
width: 16px; height: 16px;
}
}

19. 4. UIWebView for unique presentation
<img src="heart.png" class="LGautosize"/>

20. 5. Unique Subclasses
•Use Subclasses instead of conditionals
•Common behavior in parent class
•Use XIB to create proper subclass
•Device specific behavior in subclass

21. Icon Settings
Application .plist file

22. REFERENCES
Apple WWDC 2010 Session Videos: http://developer.apple.com/videos/wwdc/2010/
Sessions 103, 301, 303
Universal Icons: Apple Technical Q&A QA1686

23. CREDITS
Opening image: Icon Factory
Sample Application: Teamwork, by Calliope Learning
Cliff McCollum
cliffmcc@gmail.com
www.leadingsoftware.ca

24. Questions