【发布时间】：2012-11-07 13:50:04
【问题描述】：
我正在尝试构建一个显示来自http://news.yahoo.com/rss/ 的最新 RSS 提要的应用程序 我可以使用 NSXMLParserDelegate 解析 xml，我可以显示日期和时间以及特定提要的标题，但我也想为每个提要显示一个图像，我知道如何解析主要元素但我不知道如何传递以 url 作为键的子元素的属性...例如上述提要包含以下内容：
<item>
<title>fooo</title>
<description ahref="some link" image src="http://l1.yimg.com/bt/api/res/1.2/Wo3_apH.kz7DMvOj7MDtRQ--/YXBwaWQ9eW5ld3M7Zmk9ZmlsbDtoPTg2O3E9ODU7dz0xMzA-/http://media.zenfs.com/en_us/News/ap_webfeeds/20c464ff99815420210f6a706700a792.jpg"
</description>
我需要表格视图中来自 IMG SRC 的图像以及该特定提要的标题和日期。我很困惑如何解析 IMG SRC 属性并将其添加到我的 tableview 并改变大小，这样它就不会破坏我的标题和日期。
到目前为止我做了什么：
viewDidAppear
-(void)viewDidAppear:(BOOL)animated
{
if ([stories count] == 0)
{
NSString * path = @"http://news.yahoo.com/rss/";
[self parseXMLFileAtURL:path];
}
cellSize = CGSizeMake([newsTable bounds].size.width, 80);
}
-(void)parseXMLFileAtURL:(NSString *)URL
- (void)parseXMLFileAtURL:(NSString *)URL
{
stories = [[NSMutableArray alloc] init];
//you must then convert the path to a proper NSURL or it won't work
NSURL *xmlURL = [NSURL URLWithString:URL];
// here, for some reason you have to use NSClassFromString when trying to alloc NSXMLParser, otherwise you will get an object not found error
// this may be necessary only for the toolchain
rssParser = [[NSXMLParser alloc] initWithContentsOfURL:xmlURL];
// Set self as the delegate of the parser so that it will receive the parser delegate methods callbacks.
[rssParser setDelegate:self];
// Depending on the XML document you're parsing, you may want to enable these features of NSXMLParser.
[rssParser setShouldProcessNamespaces:NO];
[rssParser setShouldReportNamespacePrefixes:NO];
[rssParser setShouldResolveExternalEntities:NO];
[rssParser parse];
}
didStartElement
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict{
//NSLog(@"found this element: %@", elementName);
currentElement = [elementName copy];
if ([elementName isEqualToString:@"item"]) {
// clear out our story item caches...
item = [[NSMutableDictionary alloc] init];
currentTitle = [[NSMutableString alloc] init];
currentDate = [[NSMutableString alloc] init];
currentSummary = [[NSMutableString alloc] init];
currentLink = [[NSMutableString alloc] init];
}
}
找到的字符
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string{
//NSLog(@"found characters: %@", string);
// save the characters for the current item...
if ([currentElement isEqualToString:@"title"]) {
[currentTitle appendString:string];
} else if ([currentElement isEqualToString:@"link"]) {
[currentLink appendString:string];
} else if ([currentElement isEqualToString:@"description"]) {
[currentSummary appendString:string];
} else if ([currentElement isEqualToString:@"pubDate"]) {
[currentDate appendString:string];
}
}
didEndElement
- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName{
//NSLog(@"ended element: %@", elementName);
if ([elementName isEqualToString:@"item"]) {
// save values to an item, then store that item into the array...
[item setObject:currentTitle forKey:@"title"];
[item setObject:currentLink forKey:@"link"];
[item setObject:currentSummary forKey:@"summary"];
[item setObject:currentDate forKey:@"pubDate"];
}
}
didEndDocument
- (void)parserDidEndDocument:(NSXMLParser *)parser
{
[newsTable reloadData];
}
numberOfRows 和 cellForRowAtIndexPath
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [stories count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *cellIdentifier = @"cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellIdentifier] autorelease];
}
int storyIndex = [indexPath indexAtPosition: [indexPath length] - 1];
cell.textLabel.text=[[stories objectAtIndex: storyIndex] objectForKey: @"title"];
cell.detailTextLabel.text=[[stories objectAtIndex:storyIndex] objectForKey:@"pubDate"];
cell.textLabel.font=[UIFont fontWithName:@"Arial" size:12];
cell.textLabel.numberOfLines = 0;
cell.textLabel.lineBreakMode = UILineBreakModeWordWrap;
return cell;
}
如何获取单元格右侧的图像？
【问题讨论】：
-
`
fooo l1.yimg.com/bt/api/res/1.2/Wo3_apH.kz7DMvOj7MDtRQ--/…" ` -
在这里你必须解析链接和元数据......从链接下载图像，据我所知，最有效的方法是创建一个对象类来存储你必须的值显示在 tableview 单元格上，将其存储在一个可变数组中，其中包括您将要下载的图像。
-
该示例 Feed 不正确。您缺少“>”，
image部分看起来完全错误。请确认。
标签： objective-c ios nsdictionary nsxmlparser