Cache Progressive downloaded content in MPMoviePla

问题:

I have a music player implemented in iphone (sdk 4) and it works both with streaming of Mp3 (Transcoded on the fly) or raw progressive download.

Is there anyway to make the progressivedownloaded content (which I dont directly control) to be cached so it doesn redownload the whole content?

Or Is there a global cache setting to control? (On a side note, I used ASIHTTP APIs to contact my HTTP server and access data that does allow caching).

Thanks in advance.

回答1:

You can use NSURLConnection to save the file and play it back.

Example:

-(void)downloadFileAtPath:(NSString *)path
{
     NSURL *url                  = [NSURL URLWithString:path];     
     NSMutableURLRequest *req    = [NSMutableURLRequest requestWithURL:url];
      NSURLConnection* connection = [[NSURLConnection alloc] initWithRequest:req delegate:self];
    [connection start];
}

-(void)connection:(NSURLConnection*)connection didReceiveResponse:(NSURLResponse*)response
{
    //NSLog(@"%s", __PRETTY_FUNCTION__);
    [[NSFileManager defaultManager] createFileAtPath:pathForCurrentFile contents:nil attributes:nil];
     currentFile = [NSFileHandle fileHandleForUpdatingAtPath:pathForCurrentFile];
     if (currentFile)
    {
        [currentFile seekToEndOfFile];
    }
}

-(void)connection:(NSURLConnection*)connection didReceiveData:(NSData*)data
{
    //NSLog(@"%s", __PRETTY_FUNCTION__);
     if( currentFile != nil){
         if (currentFile)  {
            [currentFile seekToEndOfFile];
        }
        [currentFile writeData:data];
    }
}

-(void)connection:(NSURLConnection*)connection didFailWithError:(NSError*)error
{
    NSLog(@"%s, %@", __PRETTY_FUNCTION__, error);
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    [currentFile closeFile];
}

Below is the code for playback

//Playback
 NSString *loopFilePath = [[self applicationDocumentsDirectory].path stringByAppendingPathComponent:vidFileName];

NSURL *vidURL = [NSURL fileURLWithPath:vidFilePath];

self.vidController = [[MPMoviePlayerController alloc] initWithContentURL:vidURL];
self.vidController.view.frame = CGRectMake(0, 0, 640, 480);
self.vidController.controlStyle = MPMovieControlStyleDefault;
[self.view addSubview:self.vidController.view];
[self.vidController prepareToPlay];
[self.vidController play];