我正在创建一个RSS Feed应用程序,我的主视图控制器将显示这些Feed。我的应用程序首先没有任何错误,表现良好。最近,我添加了一个导航菜单,如下所示:http://www.appcoda.com/ios-programming-sidebar-navigation-menu/现在导航菜单不是我的问题。我的RSS列表视图完全为空,它显示空单元格。这是我的主视图controller.h:
#import <UIKit/UIKit.h>
@interface MainViewController : UIViewController <NSXMLParserDelegate>
@property (weak, nonatomic) IBOutlet UIBarButtonItem *sidebarButton;
@property (strong, nonatomic) IBOutlet UITableView *tableView;
@end
这是我的主视图Controller.m:
#import "MainViewController.h"
#import "SWRevealViewController.h"
#import "DetailViewController.h"
@interface MainViewController () {
NSXMLParser *parser;
NSMutableArray *feeds;
NSMutableDictionary *item;
NSMutableString *title;
NSMutableString *link;
NSString *element;
}
@end
@implementation MainViewController
- (void)viewDidLoad
{
[super viewDidLoad];
feeds = [[NSMutableArray alloc] init];
NSURL *url = [NSURL URLWithString:@"http://images.apple.com/main/rss/hotnews/hotnews.rss"];
parser = [[NSXMLParser alloc] initWithContentsOfURL:url];
[parser setDelegate:self];
[parser setShouldResolveExternalEntities:NO];
[parser parse];
// Change button color
_sidebarButton.tintColor = [UIColor colorWithWhite:0.1f alpha:0.9f];
// Set the side bar button action. When it's tapped, it'll show up the sidebar.
_sidebarButton.target = self.revealViewController;
_sidebarButton.action = @selector(revealToggle:);
// Set the gesture
[self.view addGestureRecognizer:self.revealViewController.panGestureRecognizer];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#pragma mark - Table View
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return feeds.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell" forIndexPath:indexPath];
cell.textLabel.text = [[feeds objectAtIndex:indexPath.row] objectForKey: @"title"];
return cell;
}
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict {
element = elementName;
if ([element isEqualToString:@"item"]) {
item = [[NSMutableDictionary alloc] init];
title = [[NSMutableString alloc] init];
link = [[NSMutableString alloc] init];
}
}
- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName {
if ([elementName isEqualToString:@"item"]) {
[item setObject:title forKey:@"title"];
[item setObject:link forKey:@"link"];
[feeds addObject:[item copy]];
}
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string {
if ([element isEqualToString:@"title"]) {
[title appendString:string];
} else if ([element isEqualToString:@"link"]) {
[link appendString:string];
}
}
- (void)parserDidEndDocument:(NSXMLParser *)parser {
[self.tableView reloadData];
}
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([[segue identifier] isEqualToString:@"showDetail"]) {
NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
NSString *string = [feeds[indexPath.row] objectForKey: @"link"];
[[segue destinationViewController] setUrl:string];
}
}
@end
感谢您的帮助!
答案 0 :(得分:1)
您可能希望在以下位置设置断点:
您还想检查在Interface Builder中是否正确设置了tableView插座以及委托和数据源