Question

如何在控制台中捕获NSXMLParser的错误？

我的项目正在使用正式的“LazyTableImages”。

问题是它不能一直工作，表没有任何价值。

这是我为获取一些调试信息所做的工作：

放置“cachePolicy：0和timeoutInterval：160.0”以避免网址超时：

NSURLRequest *urlRequest = [NSURLRequest requestWithURL:[NSURL URLWithString:TopPaidAppsFeed] cachePolicy:0 timeoutInterval:160.0]

然后添加“NSLog（@”data：％@“，string）”以检查我是否有xml当前：

NSXMLParser *parser = [[NSXMLParser alloc] initWithData:self.dataToParse];
NSString *string = [[NSString alloc] initWithData:self.dataToParse encoding:NSUTF8StringEncoding];
NSLog(@"data: %@", string);
[parser setDelegate:self];
[parser parse];

控制台在启动时显示xml，其他任何东西都可以：

2014-02-24 11:54:30.566 MyXMlParserTest[1419:1403] data: <?xml version="1.0" encoding="UTF-8"?>

之后我把它放在parseError上以检查错误但没有发生任何事情：

- (void)parser:(NSXMLParser *)parser parseErrorOccurred:(NSError *)parseError
{

    NSString * errorString = [NSString stringWithFormat:@"Unable to download data (Error code %i )",[parseError code]];

    UIAlertView * errorAlert = [[UIAlertView alloc] initWithTitle:@"Error loading content" message:errorString
                                                         delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];

    [errorAlert show];
}

然后我把“NSLog（@”nodeCount）“放在connectionDidFinishLoading上：

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    self.appListFeedConnection = nil;   // release our connection

    [UIApplication sharedApplication].networkActivityIndicatorVisible = NO;   

    // create the queue to run our ParseOperation
    self.queue = [[NSOperationQueue alloc] init];

    // create an ParseOperation (NSOperation subclass) to parse the RSS feed data
    // so that the UI is not blocked
    ParseOperation *parser = [[ParseOperation alloc] initWithData:self.appListData];

    parser.errorHandler = ^(NSError *parseError) {
        dispatch_async(dispatch_get_main_queue(), ^{
            [self handleError:parseError];
        });
    };

    // Referencing parser from within its completionBlock would create a retain
    // cycle.
    __weak ParseOperation *weakParser = parser;

    parser.completionBlock = ^(void) {
        if (weakParser.appRecordList) {
            // The completion block may execute on any thread.  Because operations
            // involving the UI are about to be performed, make sure they execute
            // on the main thread.
            dispatch_async(dispatch_get_main_queue(), ^{
                // The root rootViewController is the only child of the navigation
                // controller, which is the window's rootViewController.
                RootViewController *rootViewController = (RootViewController*)[(UINavigationController*)self.window.rootViewController topViewController];

                rootViewController.entries = weakParser.appRecordList;
                NSUInteger nodeCount = [rootViewController.entries count];
                NSLog(@"nodeCount: %lu", (unsigned long)nodeCount);
                // tell our table view to reload its data, now that parsing has completed
                [rootViewController.tableView reloadData];
            });
        }

        // we are finished with the queue and our ParseOperation
        self.queue = nil;
    };

    [self.queue addOperation:parser]; // this will start the "ParseOperation"

    // ownership of appListData has been transferred to the parse operation
    // and should no longer be referenced in this thread
    self.appListData = nil;
}

然后它返回：

014-02-24 11:54:30.582 MyXMlParserTest[1419:a0b] nodeCount: 0

从这一点开始，我不在哪里检查。我在真实和模拟器设备上尝试了这一点并且发生了相同的结果。十分之一的时间它工作和表填充。 9其他时间什么也没发生。 xml的字符串标记始终相同。只有图片网址标记正在发生变化。

Answer 1

改变这一行后确定：

__weak ParseOperation *weakParser = parser;

以下任何一个：

 ParseOperation *weakParser = parser;

或

__block ParseOperation *weakParser = parser;

问题消失了。

NSXMLParser未显示错误日志

1 个答案: