【XMLパーサ】【スレッド】XMLのパース進捗状況をプログレスバーで表示するには

Setting-progress-of-ProgressView-while-parsing-XML

##Setting progress of ProgressView while parsing XML

First, count the number of lines.

    NSError *error = nil;
    NSString *xmlFileString = [NSString stringWithContentsOfURL:url
                               encoding:NSUTF8StringEncoding error:&error];
    _totalLines = [xmlFileString componentsSeparatedByString:@"\n"].count;

Then, catch the progress in delegate method block. For example:

    - (void)parser:(NSXMLParser *)parser 
      didStartElement:(NSString *)elementName 
      namespaceURI:(NSString *)namespaceURI 
      qualifiedName:(NSString *)qName 
      attributes:(NSDictionary *)attributeDict
    {
        [self.elementStack addObject:elementName];
        
        NSOperationQueue *mainQueue = [NSOperationQueue mainQueue];
        [mainQueue addOperationWithBlock:^{
            _progressView.progress = (CGFloat)[parser lineNumber] / (CGFloat)_totalLines;
        }];
    }

Sample Project is Here:

<https://github.com/weed/p120727_XMLParseProgress>

![ss](http://farm9.staticflickr.com/8433/7758147164_1bdc0fb3b3_o.png)