向ios rss feed app添加日期的指南

Question

我使用GMNString + Html和RMXElement以及RSSItem和RSSLoader文件创建了一个iOS RSS阅读器应用程序。 现在我在我的表中有帖子标题和说明。我想知道如何在我的描述下添加帖子发布日期和时间。请具体，因为我是一个Begginer：D 更新：这是我的文件.RSSItem.m：

        #import "RSSItem.h"
    #import "GTMNSString+HTML.h"


    @implementation RSSItem

    -(NSAttributedString*)cellMessage
    {
        if (_cellMessage!=nil) return _cellMessage;

        NSDictionary* boldStyle = @{NSFontAttributeName: [UIFont fontWithName:@"Futura-CondensedMedium" size:16.0]};
        NSDictionary* normalStyle = @{NSFontAttributeName: [UIFont fontWithName:@"GillSans-LightItalic" size:16.0]};

        NSMutableAttributedString* articleAbstract = [[NSMutableAttributedString alloc] initWithString:self.title];

        [articleAbstract setAttributes:boldStyle
                                 range:NSMakeRange(0, self.title.length)];

        [articleAbstract appendAttributedString:
         [[NSAttributedString alloc] initWithString:@"\n\n"]
         ];

        int startIndex = [articleAbstract length];

        NSString* description = [NSString stringWithFormat:@"%@...", [self.description substringToIndex:100]];
        description = [description gtm_stringByUnescapingFromHTML];

        [articleAbstract appendAttributedString:
         [[NSAttributedString alloc] initWithString: description]
         ];

        [articleAbstract setAttributes:normalStyle
                                 range:NSMakeRange(startIndex, articleAbstract.length - startIndex)];

        _cellMessage = articleAbstract;
        return _cellMessage;


    }

@end

RSSItem.h：

#import <Foundation/Foundation.h>


@interface RSSItem : NSObject


@property (strong, nonatomic) NSString* title;
@property (strong, nonatomic) NSString* description;
@property (strong, nonatomic) NSURL* link;
@property (strong, nonatomic) NSAttributedString* cellMessage;

@end

RSSLoader.h：

#import <Foundation/Foundation.h>


typedef void (^RSSLoaderCompleteBlock)(NSString* title, NSArray* results);

@interface RSSLoader : NSObject

-(void)fetchRssWithURL:(NSURL*)url complete:(RSSLoaderCompleteBlock)c;

@end

RSSLoader.m：

#import "RSSLoader.h"
#import "RXMLElement.h"
#import "RSSItem.h"


@implementation RSSLoader

-(void)fetchRssWithURL:(NSURL*)url complete:(RSSLoaderCompleteBlock)callbackFunction
{

    // Create url connection and fire request
    NSURLConnection *conn = [[NSURLConnection alloc] init];
    NSURLRequest *request = [NSURLRequest requestWithURL:url];
    (void)[conn initWithRequest:request delegate:self];

    NSOperationQueue *queue = [[NSOperationQueue alloc] init];

    [NSURLConnection sendAsynchronousRequest:request queue:queue completionHandler:^(NSURLResponse *response, NSData *data, NSError *error)
     {
         NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)response;
         if ([data length] == 0 && error == nil) {
             // handle empty response
         } else if (error != nil) {
             // handle error
             NSLog(@"Error %@", [error localizedDescription]);
         } else if ([httpResponse statusCode] == 200) {
             RXMLElement *rss = [RXMLElement elementFromXMLData:data];
             RXMLElement *rssChild = [rss child:@"channel"];
             RXMLElement* title = [rssChild child:@"title"];
             NSArray* items = [[rss child:@"channel"] children:@"item"];

             NSMutableArray* result = [NSMutableArray arrayWithCapacity:items.count];

             //more code
             for (RXMLElement *e in items) {

                 //iterate over the articles
                 RSSItem* item = [[RSSItem alloc] init];
                 item.title = [[e child:@"title"] text];
                 item.description = [[e child:@"description"] text];
                 item.link = [NSURL URLWithString: [[e child:@"link"] text]];
                 if (item.link != NULL) {
                     [result addObject: item];
                 }
             }

             callbackFunction([title text], result);
         }
     }];

}

@end

MasterViewController.m：

#import "MasterViewController.h"
#import "DetailViewController.h"
#import "TableHeaderView.h"
#import "RSSLoader.h"
#import "RSSItem.h"


@interface MasterViewController ()

{

    NSArray *_objects;
    NSURL* feedURL;
    UIRefreshControl* refreshControl;
}
@end

@implementation MasterViewController
{
    NSMutableArray *tableData;

}


- (void)viewDidLoad
{
    [super viewDidLoad];
    //configuration
    self.title = @"آخرین اخبار";
    feedURL = [NSURL URLWithString:@"http://appleapps.ir/feed"];

    //add refresh control to the table view
    refreshControl = [[UIRefreshControl alloc] init];

    [refreshControl addTarget:self
                       action:@selector(refreshInvoked:forState:)
             forControlEvents:UIControlEventValueChanged];

    NSString* fetchMessage = [NSString stringWithFormat:@"در حال بروزرسانی %@",feedURL];

    refreshControl.attributedTitle = [[NSAttributedString alloc] initWithString:fetchMessage
                                                                     attributes:@{NSFontAttributeName:[UIFont fontWithName:@"Helvetica" size:11.0]}];


    [self.tableView addSubview: refreshControl];

    //add the header
    self.tableView.tableHeaderView = [[TableHeaderView alloc] initWithText:@"در حال بروزرسانی..."];


    [self refreshFeed];
}

-(void) refreshInvoked:(id)sender forState:(UIControlState)state
{
    [self refreshFeed];
}

-(void)refreshFeed
{
    RSSLoader* rss = [[RSSLoader alloc] init];
    [rss fetchRssWithURL:feedURL
                complete:^(NSString *title, NSArray *results) {

                    //completed fetching the RSS
                    dispatch_async(dispatch_get_main_queue(), ^{

                        //UI code on the main queue
                        [(TableHeaderView*)self.tableView.tableHeaderView setText:title];

                        _objects = results;
                        [self.tableView reloadData];

                        // Stop refresh control
                        [refreshControl endRefreshing];
                    });
                }];

}

#pragma mark - Table View

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return _objects.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell" forIndexPath:indexPath];

    RSSItem *object = _objects[indexPath.row];
    cell.textLabel.attributedText = object.cellMessage;
    cell.textLabel.numberOfLines = 0;
    [cell.textLabel setTextAlignment:UITextAlignmentRight];
    return cell;
}

-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    RSSItem *item = [_objects objectAtIndex:indexPath.row];
    CGRect cellMessageRect = [item.cellMessage boundingRectWithSize:CGSizeMake(200,200000)
                                                            options:NSStringDrawingUsesLineFragmentOrigin
                                                            context:nil];
    return cellMessageRect.size.height;
}

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([[segue identifier] isEqualToString:@"showDetail"]) {
        NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
        RSSItem *object = _objects[indexPath.row];
        [[segue destinationViewController] setDetailItem:object];
    }
}



@end