我正在尝试放置一个在下载过程中同步的进度条。
我的应用程序现在可以使用此代码下载文件...
pdfData = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:@"http://webaddress.com/pro/download/file.pdf"]];
NSString *resourcePDFPath = [[NSString alloc] initWithString:[[[[NSBundle mainBundle] resourcePath] stringByDeletingLastPathComponent] stringByAppendingPathComponent:@"Documents"]];
pdfFilePath = [resourcePDFPath stringByAppendingPathComponent:@"myPDF.pdf"];
[pdfData writeToFile:pdfFilePath atomically:YES];
在这段代码的过程中，应用在下载过程中停止了，这是否正常？
现在我想要的是在下载的那个停止时间放置一个进度条。
我试着查看我在网上找到的代码，但我有点困惑，我想我需要一个逐步解释清楚的引用。
使用 AFNetworking ,
这里progress是UIProgressview
#import <AFNetworking/AFNetworking.h>//add to the header of class
-(void)downloadShowingProgress
{
progress.progress = 0.0;
currentURL=@"http://www.selab.isti.cnr.it/ws-mate/example.pdf";
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:currentURL]];
AFURLConnectionOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *filePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"MY_FILENAME_WITH_EXTENTION.pdf"];
operation.outputStream = [NSOutputStream outputStreamToFileAtPath:filePath append:NO];
[operation setDownloadProgressBlock:^(NSUInteger bytesRead, NSUInteger totalBytesRead, NSUInteger totalBytesExpectedToRead) {
progress.progress = (float)totalBytesRead / totalBytesExpectedToRead;
}];
[operation setCompletionBlock:^{
NSLog(@"downloadComplete!");
}];
[operation start];
}
使用 NSURLConnection
-(void)downloadWithNsurlconnection
{
NSURL *url = [NSURL URLWithString:currentURL];
NSURLRequest *theRequest = [NSURLRequest requestWithURL:url cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:60];
receivedData = [[NSMutableData alloc] initWithLength:0];
NSURLConnection * connection = [[NSURLConnection alloc] initWithRequest:theRequest delegate:self startImmediately:YES];
}
- (void) connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
progress.hidden = NO;
[receivedData setLength:0];
expectedBytes = [response expectedContentLength];
}
- (void) connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
[receivedData appendData:data];
float progressive = (float)[receivedData length] / (float)expectedBytes;
[progress setProgress:progressive];
}
- (void) connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
}
- (NSCachedURLResponse *) connection:(NSURLConnection *)connection willCacheResponse: (NSCachedURLResponse *)cachedResponse {
return nil;
}
- (void) connectionDidFinishLoading:(NSURLConnection *)connection {
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *pdfPath = [documentsDirectory stringByAppendingPathComponent:[currentURL stringByAppendingString:@".mp3"]];
NSLog(@"Succeeded! Received %d bytes of data",[receivedData length]);
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
[receivedData writeToFile:pdfPath atomically:YES];
progress.hidden = YES;
}