Question

我的新应用程序遇到了小问题。一开始我认为这只是线程的问题，但现在我觉得我必须重写一半代码来修复它。在此之前，你可能会帮助我:)。

现在我正在编写将从服务器下载内容的应用程序。我们有两个对象：MainViewController其中UI和DataManager我正在处理文件。在开始时，我正在DataManager中检查服务器上的更改：

[NSURLConnection sendAsynchronousRequest:[[NSURLRequest alloc] initWithURL:dataURL] queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
            if (error) {
                //Data was not downloaded
            } else {
                //Downloading data base
                [[NSOperationQueue mainQueue] addOperationWithBlock:^{

                    if (dataFileExists) { //compare and save downloaded data base: localDataArray i downloadedDataArray

                        if ([localDataArray isEqual:DownloadedDataArray]) {
                            [self.delegate dataWasLoaded];
                        }
                    } else {

                        [self synchronizeAllTheFiles]; //Data base sync

                        [self.delegate dataWasLoaded];
                    }

                }];
            }
        }];

接下来，当我知道服务器上存在差异时，我会同步所有数据。有两种委托方法：beginUploadDataBaseWithNumberOfObjectsToDownload和fileWasDownloaded。

首先检查要下载的文件数量。

第二次为下载的文件添加+1。此方法的代表位于MainViewController。

- (void)synchronizeAllTheFiles {
    NSMutableArray *arrayWithLinksToDownload = [[NSMutableArray alloc] init];                               //Table of links

    [self.delegate beginUploadDataBaseWithNumberOfObjectsToDownload:[arrayWithLinksToDownload count]]; //How many things are to download

    for (int d = 0; d < [arrayWithLinksToDownload count]; d++) { //Runloop to download links
                                          //Downloading Data

        if (urlData) {                                                                                      //If data was downloaded

            [urlData writeToFile:filePath atomically:YES];                                                  //Save on device

            [self.delegate fileWasDownloaded]; //MainViewController Add next downloaded file
        }
    }
}

MainViewController中有委托方法：

- (void)beginUploadDataBaseWithNumberOfObjectsToDownload:(int)numberToDownload {
    IfDownloadingData = YES;
    ItemsToDownloadCount = numberToDownload;
    ItemsDownloadedCount = 0;
}

- (void)fileWasDownloaded {
    ItemsDownloadedCount++;
    float progress = (float)ItemsDownloadedCount/(float)ItemsToDownloadCount;
    NSLog(@"%ld/%li - %f", (long)ItemsDownloadedCount, (long)ItemsToDownloadCount, progress);
    [self.LoadingProgressView setProgress:progress animated:YES];
}

问题是 ProgressView 不想更新其状态。我正在尝试添加调度块，但是如果ProgressView在主线程中没有在屏幕上更改。我试图通过NSTimer来管理它并发送书籍，但遗憾的是存在问题。

我会很高兴得到任何帮助:)。

Answer 1

您只需将更新GUI代码放在主线程中，而不是其他任何内容。

 dispatch_async(dispatch_get_main_queue(), ^{
     [self.LoadingProgressView setProgress:progress animated:YES];
 });

然后乘坐addOperationWithBlock行：

[NSURLConnection sendAsynchronousRequest:[[NSURLRequest alloc] initWithURL:dataURL] queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
        if (error) {
            //Data was not downloaded
        } else {
            // **Remove this line**
            // [[NSOperationQueue mainQueue] addOperationWithBlock:^{

                if (dataFileExists) { //compare and save downloaded data base: localDataArray i downloadedDataArray

                    if ([localDataArray isEqual:DownloadedDataArray]) {
                        [self.delegate dataWasLoaded];
                    }
                } else {

                    [self synchronizeAllTheFiles]; //Data base sync

                    [self.delegate dataWasLoaded];
                }
            // **Remove this line**
            // }];
        }
    }];

而且，我看不到你在哪里得到urlData。但无论如何，这个循环不应该在主线程中，因为它会使主线程忙，因此无法更新GUI。

for (int d = 0; d < [arrayWithLinksToDownload count]; d++) { //Runloop to download links

        //Downloading Data

        if (urlData) {                                                                                     
            //If data was downloaded
            [urlData writeToFile:filePath atomically:YES];                                                 
            //Save on device
            [self.delegate fileWasDownloaded]; //MainViewController Add next downloaded file
        }

UIProgressView未更新状态

1 个答案: