How to download audio files from a server into my iPhone application?

Question

I have an iphone application which plays audio files (mp3) from a server, I want to add a download button so the user can download these files into the app. So he/she will not need the Internet connection each time they want to listen to these files. Does any one has a sample code for that ?

I saw many things on the web but I'm still confusion. Here is the code I'm using :

in the .h File :

#import 
#import "MBProgressHUD.h"

#import 
#import 

@interface myViewController : UIViewController {
MBProgressHUD *HUD;

long long expectedLength;
long long currentLength;

AVAudioPlayer *theAudio;

}

-(NSString *)pathOfFile;
-(void)applicationWillTerminate:(NSNotification*)notification;

-(IBAction)play:(id)sender;
-(IBAction)download(id)sender;
@property (nonatomic,retain) AVAudioPlayer *theAudio;

in the .m File:

- (IBAction)download:(id)sender {
NSURL *URL = [NSURL URLWithString:@"http://www.server.com/myfile.mp3"];
NSURLRequest *request = [NSURLRequest requestWithURL:URL];

NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request      delegate:self];
[connection start];
[connection release];

HUD = [[MBProgressHUD showHUDAddedTo:self.navigationController.view animated:YES] retain];

HUD.labelText = @"Loading...";
}

-(IBAction)play:(id)sender { 

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

NSString *documentsDirectory = [paths objectAtIndex:0];

NSString *file = [NSString stringWithFormat:@"%@/song.mp3", documentsDirectory];

theAudio = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:file]   error:nil];

[theAudio play];

}

-(NSString *)pathOfFile {

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

NSString *documentsDirectory = [paths objectAtIndex:0];

return [documentsDirectory stringByAppendingFormat:@"myfile.plist"];

}

-(void)applicationWillTerminate:(NSNotification*)notification {

NSMutableArray *array = [[NSMutableArray alloc]init];
[array addObject:theAudio];
[array writeToFile:[self pathOfFile] atomically:YES];

[array release];

}

I don't know what is the problem or what I'm missing over here , can you please help me with more details ? Thanks in advance.

Answer 1

Try below code:

ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:urlStr]];
[request setDownloadDestinationPath:destinationPath];   
[request setTemporaryFileDownloadPath:[NSString stringWithFormat:@"%@-part",destinationPath]];
[request setDelegate:self];
[request setAllowResumeForFileDownloads:YES];
[request startAsynchronous];

And to check downloads:

- (void)requestStarted:(ASIHTTPRequest *)request;
- (void)request:(ASIHTTPRequest *)request didReceiveResponseHeaders:(NSDictionary *)responseHeaders;
- (void)request:(ASIHTTPRequest *)request willRedirectToURL:(NSURL *)newURL;
- (void)requestFinished:(ASIHTTPRequest *)request;
- (void)requestFailed:(ASIHTTPRequest *)request; 

Above code will create a file "your_file.mp3-part" in destination folder while download in progress and "your_file.mp3" when download completes.

Hope it helps. Let me know if any doubts.

Answer 2

Use ASIHTTP for downloading, it asynchronous and more reliable. http://allseeing-i.com/ASIHTTPRequest/ This is the method through which you can download audios/videos. Pass parameter to it and start download?

Parameters: (1) File Path , Document Directory path where you want to save (2) Trimmed String , which is the lecture URL

+ (void)downloadingLecture:(NSString *)filePath withLectureUrl:(NSString *)trimmedString 
 {
    AppDelegate *_appDel=(AppDelegate *)[[UIApplication sharedApplication] delegate];
    [_appDel.queue setDelegate:self];
    [_appDel.queue setMaxConcurrentOperationCount:10];
    [_appDel.queue setShouldCancelAllRequestsOnFailure:NO];
    [_appDel.queue setShowAccurateProgress:YES];

    ASIHTTPRequest *request;
    request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:trimmedString]];
    [request setDelegate:self];
    [request setDownloadDestinationPath:filePath];
    [request setShowAccurateProgress:YES];
    [request setShouldContinueWhenAppEntersBackground:YES];
    [request setUsername:downloadedSuccessfullString];
    [request setDidFinishSelector:@selector(downloadedSuccessfully:)];
    [request setDidFailSelector:@selector(downloadedFailure:)];

    [_appDel.queue addOperation:request];
    [_appDel.queue go];
}

Hope this will help you. If still issue then email me, I am sure I will do it, because I have implemented it in my two applications.