//
//  AppController.h
//  RSS Reader
//
//  Created by longx-app on 13-9-14.
//  Copyright (c) 2013年 longx-app. All rights reserved.
//

#import <Foundation/Foundation.h>@interface AppController : NSTableView <NSTableViewDataSource>
{NSXMLDocument* document;IBOutlet id linkTextField;IBOutlet id titleTextField;IBOutlet id urlTextField;IBOutlet NSTableView *tableView;
}- (IBAction)readURL:(id)sender;@end

//
//  AppController.m
//  RSS Reader
//
//  Created by longx-app on 13-9-14.
//  Copyright (c) 2013年 longx-app. All rights reserved.
//

#import "AppController.h"@implementation AppController// NSTableView数据资源
- (NSInteger)numberOfRowsInTableView:(NSTableView *)tableView
{if (!document) {return 0;}// 取得 “/rss/channel/item” 节点NSArray*    nodes;nodes = [document nodesForXPath:@"/rss/channel/item" error:NULL];if ([nodes count] == 0) {// 取得 “/rdf:RDF/item” 节点nodes = [document nodesForXPath:@"/rdf:RDF/item" error:NULL];}if ([nodes count] == 0) {// 取得 “/feed/entry” 节点nodes = [document nodesForXPath:@"/feed/entry" error:NULL];}// 返回节点的个数return [nodes count];
}- (id)tableView:(NSTableView *)tableView objectValueForTableColumn:(NSTableColumn *)tableColumn row:(NSInteger)row
{// 判断实例变量document是否有效，无效则退出处理if (!document) {return nil;}// 使用identifier方法取得参数tableColumn的识别符，此识别符会用于后面列的判别id identifier;identifier = [tableColumn identifier];// 对 XML 文档使用 nodesForXPath: 方法取得 item 节点数组// 取得 “/rss/channel/item” 节点NSArray*    nodes;nodes = [document nodesForXPath:@"/rss/channel/item" error:NULL];if ([nodes count] == 0) {// 取得 “/rdf:RDF/item” 节点nodes = [document nodesForXPath:@"/rdf:RDF/item" error:NULL];}if ([nodes count] == 0) {// 取得 “/feed/entry” 节点nodes = [document nodesForXPath:@"/feed/entry" error:NULL];}// 根据行参数row取得指定行的item节点NSXMLNode*  node;node = [nodes objectAtIndex:row];// 以下使用识别符来判断具体的列，首先是title列，从item节点中取得title节点，找到// title的值后，返回此值if ([identifier isEqual:@"title"]) {// 取得 “title” 的字符串nodes = [node nodesForXPath:@"title" error:NULL];if ([nodes count] == 1) {node = [nodes objectAtIndex:0];return [node stringValue];}}// 其次是link列，从item节点，找到后返回link值。if ([identifier isEqual:@"link"]) {// 取得 ”link“ 的字符串nodes = [node nodesForXPath:@"link" error:NULL];if ([nodes count] == 1) {node = [nodes objectAtIndex:0];return [node stringValue];}}return nil;
}- (IBAction)readURL:(id)sender
{NSURL* url;url = [NSURL URLWithString:[urlTextField stringValue]];// 创建XML文档，这里的URL如果是远程文件的话，必须以http://或ftp://开头，如果是// 本地的，必须以file:///开头document = [[NSXMLDocument alloc] initWithContentsOfURL:url options:0 error:NULL];if (!document) {return;}// 取得 “/rss/channel/title” 节点NSArray*    nodes;nodes = [document nodesForXPath:@"/rss/channel/title" error:NULL];if ([nodes count] == 0) {// 取得 “/rdf:RDF/channel/title” 节点nodes = [document nodesForXPath:@"/rdf:RDF/channel/title" error:NULL];}if ([nodes count] == 0) {// 取得 “/feed/title” 节点nodes = [document nodesForXPath:@"/feed/title" error:NULL];}if ([nodes count] == 1) {NSXMLNode* titleNode;titleNode = [nodes objectAtIndex:0];// 设置RSS文档的标题NSString*   title;title = [titleNode stringValue];[titleTextField setStringValue:title];}// 取得 “/rss/channel/link” 节点nodes = [document nodesForXPath:@"/rss/channel/link" error:NULL];if ([nodes count] == 0) {// 取得 “/rdf:RDF/channel/link” 节点nodes = [document nodesForXPath:@"/rdf:RDF/channel/link" error:NULL];}if ([nodes count] == 0) {// 取得 “/feed/link” 节点nodes = [document nodesForXPath:@"/feed/link" error:NULL];}if ([nodes count] == 1) {NSXMLNode* linkNode;linkNode = [nodes objectAtIndex:0];// 设置RSS文档对应网页的URLNSString* link;link = [linkNode stringValue];[linkTextField setStringValue:link];}// 表格数据读入
    [tableView reloadData];
}@end