【发布时间】：2011-09-26 08:58:42
【问题描述】：
我有一个由 xml 解析的数据填充的 UITableView。解析有效，但表格保持空白。
控制台显示 xml 形式的 url 被解析并显示其组件。它还显示了当在不同的函数中询问时 tableview 的行应该具有的对象数，但 numberOfRowsInSection: 返回 Null。因此，Simulator 中的 tableView 保持空白。
这是我的代码。这是教程中的简单代码：
+++++++++++++++++ RootViewController.h++++++++++++++++++++++
#import < UIKit/UIKit.h >
@interface RootViewController : UITableViewController < NSXMLParserDelegate >{
IBOutlet UITableView *newsTable;
UIActivityIndicatorView *activityIndicator;
CGSize cellSize;
NSXMLParser *rssParser;
NSMutableArray *stories;
NSMutableDictionary *item;
NSString *currentElement;
NSMutableString *currentTitle, *currentDate, *currentSummary, *currentLink;
}
@property (nonatomic, retain) NSMutableArray *stories;
@property (nonatomic, retain) IBOutlet UITableView *newsTable;
-(void)parseXMLFileAtURL:(NSString *)URL;
@end
+++++++++++++++++++++++++++ RootViewController.m ++++++++++++++++++++++++++++++++++++++
#import "RootViewController.h"
@implementation RootViewController
@synthesize newsTable, stories;
-(void)viewDidLoad {
[super viewDidLoad];
// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
// self.navigationItem.rightBarButtonItem = self.editButtonItem;
}
-(void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
[newsTable reloadData];
}
-(void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
if([stories count] == 0){
NSString *path = @"http://feeds.feedburner.com/TheAppleBlog";
[self parseXMLFileAtURL:path];
}
cellSize = CGSizeMake([newsTable bounds].size.width, 60);
}
// Customize the number of sections in the table view.
-(NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
-(void)parseXMLFileAtURL:(NSString *)URL {
stories = [[NSMutableArray alloc] init];
NSURL *xmlURL = [NSURL URLWithString:URL];
rssParser = [[NSXMLParser alloc] initWithContentsOfURL:xmlURL];
[rssParser setDelegate:self];
[rssParser setShouldProcessNamespaces:NO];
[rssParser setShouldReportNamespacePrefixes:NO];
[rssParser setShouldResolveExternalEntities:NO];
[rssParser parse];
}
-(void)parserDidStartDocument:(NSXMLParser *)parser{
NSLog(@"Found file and started parsing");
}
-(void) parser:(NSXMLParser *)parser parseErrorOccurred:(NSError *)parseError{
NSString *errorString = [NSString stringWithFormat:@"Unable to download story feed from the website (error code %i)", [parseError code]];
NSLog(@"error parsing XML: %@", errorString);
UIAlertView *errorAlert = [[UIAlertView alloc]:@"Error loading content" message:errorString delegate:self cancelButtonTitle:@"OK" otherButtonTitle:nil];
[errorAlert show];
}
-(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"]) {
item = [[NSMutableDictionary alloc] init];
currentTitle = [[NSMutableString alloc] init];
currentDate = [[NSMutableString alloc] init];
currentSummary = [[NSMutableString alloc] init];
currentLink = [[NSMutableString alloc] init];
}
}
-(void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName {
NSLog(@"End this Element %@", elementName);
if ([elementName isEqualToString:@"item"]) {
[item setObject:currentTitle forKey:@"title"];
[item setObject:currentLink forKey:@"link"];
[item setObject:currentSummary forKey:@"summary"];
[item setObject:currentDate forKey:@"date"];
[stories addObject:[item copy]];
NSLog(@"adding Story : %@",currentTitle);
}
}
// Customize the number of rows in the table view.
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
NSLog(@"Count is = %@", [stories count]);
return [stories count];
}
-(void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string{
NSLog(@"Found characters: %@", string);
if([currentElement isEqualToString:@"title"]){
[currentTitle appendString:string];
NSLog(@"The Title is : %@", currentTitle);
}
else if([currentElement isEqualToString:@"link"]){
[currentLink appendString:string];
NSLog(@"The Link is : %@", currentLink);
}
else if([currentElement isEqualToString:@"description"]){
[currentSummary appendString:string];
NSLog(@"The summary is : %@", currentSummary);
}
else if([currentElement isEqualToString:@"pubDate"]){
[currentDate appendString:string];
NSLog(@"The Date is : %@", currentDate);
}
}
-(void)parserDidEndDocument:(NSXMLParser *)parser{
[activityIndicator stopAnimating];
[activityIndicator removeFromSuperview];
NSLog(@"Stories array has %d items", [stories count]);
NSLog(@"Stories are : %@",stories);
}
// Customize the appearance of table view cells.
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *MyIdentifier = @"MyIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:MyIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:MyIdentifier] autorelease];
}
// Configure the cell.
cell.textLabel.text = (NSString *)[[stories objectAtIndex:indexPath.row] objectForKey:@"title"];
return cell;
}
-(void)dealloc {
[super dealloc];
[newsTable release];
[currentDate release];
[currentElement release];
[currentSummary release];
[currentLink release];
[stories release];
[item release];
[currentTitle release];
[rssParser release];
}
【问题讨论】：
-
@TechZen - 您的编辑非常出色，感谢您抽出时间在今天和其他几篇文章中帮助其他人。
-
@Tim Post -- 没什么大不了的，我现在正躺着，所以我在打发时间，因为我无法完成任何真正的工作。
标签： ios4 uitableview nsxmlparser