1. EEC-492/693/793 iPhone Application Development
Lecture 21
Wenbing Zhao & Nigamanth Sridhar
4/11/2019
4/11/2019
EEC492/693/793 - iPhone Application Development
EEC492/693/793 - iPhone Application Development 1

2. Outline Accessing build-in applications Assignment:
Build the and PhotoLibrary apps
4/11/2019
4/11/2019
EEC492/693/793 - iPhone Application Development
EEC492/693/793 - iPhone Application Development 2

3. Invoking Build-in Applications
[[UIApplication sharedApplication] openURL:url]
NSString * String =
url = [NSURL URLWithString: String];
Safari: url = [NSURL
Phone: url = [NSURL
SMS: url = [NSURL
Drawback: calling app will be put to background, user must manually switch back to the app
4/11/2019
EEC492/693/793 - iPhone Application Development

4. Invoking the Build-in App without Leaving the Current App
Invoking the Mail composer UI
Use MFMailComposeViewController
Invoking the Message composer UI
Use MFMessageComposeViewController
-(IBAction) btnCompose (id) sender {
MFMailComposeViewController *picker =
[[MFMailComposeViewController alloc] init];
picker.mailComposeDelegate = self;
[picker subject here”];
[picker body here” isHTML:NO];
[self presentModalViewController:picker animated:YES];
[picker release]; }
- (void)mailComposeController:(MFMailComposeViewController*)controller
didFinishWithResult:(MFMailComposeResult)result error:(NSError*)error {
[controller dismissModalViewControllerAnimated:YES];
4/11/2019
EEC492/693/793 - iPhone Application Development

5. The Image Picker Interface
UIImagePickerController
Handles all user and device interactions
UIViewController subclass
UIImagePickerControllerDelegate
Implemented by your delegate object
Steps for using the image picker
Check the source availability:
isSourceTypeAvailable: class method
Assign a delegate object
Present the controller modally
4/11/2019
EEC492/693/793 - iPhone Application Development

6. Displaying the Image Picker
Called from a view controller
if ([UIImagePickerController isSourceTypeAvailable:
UIImagePickerControllerSourceTypeCamera]) {
UIImagePickerController* picker = [[UIImagePickerController alloc] init];
picker.sourceType = UIImagePickerControllerSourceTypeCamera;
picker.delegate = self;
// picker.allowsEditing = YES;
[self presentModalViewController:picker animated:YES]; }
enum {
UIImagePickerControllerSourceTypePhotoLibrary,
UIImagePickerControllerSourceTypeCamera,
UIImagePickerControllerSourceTypeSavedPhotosAlbum };
typedef NSUInteger UIImagePickerControllerSourceType;
4/11/2019
EEC492/693/793 - iPhone Application Development

7. Defining Your Delegate Object
Accept case
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
// Check media type, and save or use the media here
[self dismissModalViewControllerAnimated:YES]; // Dismiss the image picker
[picker release]; }
Cancel case
- (void)imagePickerControllerDidCancel:
(UIImagePickerController*)picker
// Dismiss the image picker.
[self dismissModalViewControllerAnimated:YES];
4/11/2019
EEC492/693/793 - iPhone Application Development

8. EEC492/693/793 - iPhone Application Development
More on the Accept Case
If an image was picked, a dictionary containing the image is passed in
If a movie was picked, a filesystem URL for the movie is passed in
- (void)imagePickerController:(UIImagePickerController *)picker
didFinishPickingMediaWithInfo:(NSDictionary *)info {
UIImage *image;
NSURL *mediaUrl = (NSURL *)[info valueForKey:UIImagePickerControllerMediaURL];
if (mediaUrl == nil) {
image = (UIImage *) [info valueForKey:UIImagePickerControllerEditedImage];
if (image == nil) {
//---original image selected---
image = (UIImage *) [info valueForKey:UIImagePickerControllerOriginalImage];
//---display the image--- }
else //---edited image picked--- {
// handle the image here
else {
//---video picked---
4/11/2019
EEC492/693/793 - iPhone Application Development

9. Accessing the Videos in the Photo Library
Specify media types before launch the image picker (default is image only)
NSArray *mediaTypes =
[NSArray arrayWithObjects:kUTTypeImage, kUTTypeMovie, nil];
imagePicker.mediaTypes = mediaTypes;
To play the video picked (works only in ios 4)
#import <MediaPlayer/MediaPlayer.h>
#import <MobileCoreServices/MobileCoreServices.h>
MPMoviePlayerController *player = [[MPMoviePlayerController alloc]
initWithContentURL:mediaUrl];
[[NSNotificationCenter defaultCenter] addObserver:self
name:MPMoviePlayerPlaybackDidFinishNotification object:player];
//---play partial screen---
player.view.frame = CGRectMake(0, 0, 320, 460);
[self.view addSubview:player.view];
[player play];
4/11/2019
EEC492/693/793 - iPhone Application Development

10. Accessing the Videos in the Photo Library
Cleaning up when video is done playing
- (void) movieFinishedCallback:(NSNotification*) aNotification {
MPMoviePlayerController *player = [aNotification object];
[[NSNotificationCenter defaultCenter] removeObserver:self
name:MPMoviePlayerPlaybackDidFinishNotification object:player];
[player.view removeFromSuperview];
[player autorelease]; }
4/11/2019
EEC492/693/793 - iPhone Application Development