Example of case implementation in iPhone development applications

IPhone DevelopmentThe example of case implementation in the application is the content to be introduced in this article, mainly to learn the implementation process of the following small cases, to see the details.

I. Read the image code from the iPhone/iPad Image Library

If your App involves reading images from the iPhone/iPad image library, you can read the code shared by the CocoaChina moderator angellixf, which saves you a lot of time.

 
 

  
  
UIImagePickerController * picker = [[UIImagePickerController alloc] init];
  
  
Picker. delegate = self;
  
  
Picker. sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
  
  
[Self presentModalViewController: picker animated: YES];
  
  
 
  
  
UIImagePickerControllerSourceTypePhotoLibrary, // photo library
  
  
UIImagePickerControllerSourceTypeCamera // obtain the image from the camera
  
  
UIImagePickerControllerSourceTypeSavedPhotosAlbum // This is a custom library, which is saved by the user or
 
 

Ii. Code for saving images to the Photo Library:

 
 

  
  
UIImageWriteToSavedPhotosAlbum(Image, self, @selector(image:didFinishSavingWithError:contextInfo:), nil); 
 
 

Parse NSString xml Code

Questions raised by the CocoaChina member "marshluca:

 
 

  
  
NSString *xmlString = @"<person><name>Jack</name><age>13< /age></person>"; 
 
 

How to construct an NSXML for this xmlString and parse the constructed NSXML.

Solution: first convert to NSData and then use NSXMlParser for parsing. Code:

 
 

  
  
- (void)handleXMLData {       
  
  
    NSString *myString = @"<addresses owner='swilson'><person><lastName>Doe</lastName><firstName>John</firstName></person></addresses>";   
  
  
    NSData *myRequestData = [ NSData dataWithBytes: [myString UTF8String]  length:[myString length]];     
  
  
    NSXMLParser *myParser = [[NSXMLParser alloc] initWithData:myRequestData];   
  
  
    [myParser setDelegate:self];   
  
  
    [myParser setShouldProcessNamespaces:YES];   
  
  
    [myParser setShouldReportNamespacePrefixes:YES];   
  
  
    [myParser setShouldResolveExternalEntities:NO];   
  
  
    BOOL success = [myParser parse];   
  
  
    [myParser release]; 
 
 

Post address http://www.cocoachina.com/bbs/read.php? Tid-20278.html

3. Code for playing background music and buttons on iPhone

1. Background MusicPlaySupports loop playback of long music in mp3 format

This method of playing music is imported into the framework # import <AVFoundation/AVFoundation. h>;

 
 

  
  
NSString * musicFilePath = [[NSBundle mainBundle] pathForResource: @ "changan" ofType: @ "mp3"]; // create a music file path
  
  
NSURL * musicURL = [[NSURL alloc] initFileURLWithPath: musicFilePath];
  
  
 
  
  
AVAudioPlayer * thePlayer = [[AVAudioPlayer alloc] initWithContentsOfURL: musicURL error: nil];
  
  
 
  
  
// Create a player
  
  
Self. myBackMusic = thePlayer; // assign a value to the class variable defined by yourself
  
  

  
  
[MusicURL release];
  
  
[ThePlayer release];
  
  

  
  
[MyBackMusic prepareToPlay];
  
  
[MyBackMusic setVolume: 1]; // sets the volume.
  
  
MyBackMusic. numberOfLoops =-1; // set the number of times the music is played-1 to keep repeating
  
  
If (mainMusicStatus)
  
  
{
  
  
[MyBackMusic play]; // playback
  
  
}
 
 

2. Button playing sound

You need to import the framework # import <AudioToolbox/AudioToolbox. h>

 
 

  
  
NSString * thesoundFilePath = [[NSBundle mainBundle] pathForResource: @ "Clapping Crowd Studio 01" ofType: @ "caf"]; // create a music file path
  
  
CFURLRef thesoundURL = (CFURLRef) [NSURL fileURLWithPath: thesoundFilePath];
  
  
AudioServicesCreateSystemSoundID (thesoundURL, & sameViewSoundID );
  
  
 
  
  
// The SoundID variable corresponds to the URL
  
  
 
  
  
AudioServicesPlaySystemSound (sameViewSoundID); // play the SoundID sound
 
 

Summary:IPhone DevelopmentThe example of case implementation in the application has been introduced. I hope this article will help you!