320学习笔记 2

20110625

http://www.cnblogs.com/scorpiozj/archive/2011/06/27/2091259.html

做iphone的，UINavigationController+UItableViewController组合的应用是必须会的，那么我们必须学习下如何使用320来实现此类应用。

考虑这样的需求：点击tableview上的feed行就从apple store上获取排名前10的专辑信息，链接：http://itunes.apple.com/us/rss/topalbums/limit=10/explicit=true/xml.  具体流程:程序启动后是一tableview（图1）,点击rss 后在tableview中显示所有专辑信息,每个cel（图2）l中左边是专辑图片,右上是歌手名,右下是专辑名.流程很简单,页面显示就两个:通常rooview+detailView就搞定,此外还需要一个获取数据的类就OK了.参考了320的一种现成的cell式样,好像没有和我们所需相同的,那么我们需要自定义cell.

 图1

图2

在开始工程前，我们首先看一下320中实现上述的tableview的一个大致框架（图3）：

图3

在UIKit下，tableview的实现主要通过设置tableview的datasource和delegate，这是苹果典型的MVC思维。在320中也贯彻了MVC思想：需要tableviewController，dataSource，tableItem，tableItemCell，Model以及object。datasource，顾名思义是为tableview提供数据，它首先生成model来获得所需数据（FeedObj)，然后根据原数据的类型生成相应的tableItem,最后根据tableItem来选择合适的tableItemCell。

下面我们开始创建工程,可以选择xcode的viewController模板,然后将320添加进工程(过程略,参见官方的脚本文件).做好以上设置后,就可以开始了.我们大概需要以下类文件:rootViewController,tableViewController,tableItem,tableItemCell,Model,dataSource和obj.

以下将代码列出,并做简单说明.

MyThree20ProjAppDelegate主要的操作是生成url映射.

#import <UIKit/UIKit.h>

@class MyThree20ProjViewController;

@interface MyThree20ProjAppDelegate : NSObject <UIApplicationDelegate> {
    UIWindow *window;
    MyThree20ProjViewController *viewController;
}

@property (nonatomic, retain) IBOutlet UIWindow *window;
@property (nonatomic, retain) IBOutlet MyThree20ProjViewController *viewController;

@end


#import "MyThree20ProjAppDelegate.h"
#import "MyThree20ProjViewController.h"

#import <Three20/Three20.h>



@implementation MyThree20ProjAppDelegate

@synthesize window;
@synthesize viewController;

- (void)applicationDidFinishLaunching:(UIApplication *)application {
    TTNavigator *navigator = [TTNavigator navigator];
    navigator.persistenceMode = TTNavigatorPersistenceModeAll;
    navigator.window = self.window;
        
    TTURLMap *map = navigator.URLMap;
    
    // Any URL that doesn't match will fall back on this one, and open in the web browser
//    [map from:@"*" toViewController:[TTWebController class]];
    
    [map from:@"tt://root" toSharedViewController:NSClassFromString(@"MyThree20ProjViewController")];
    
    [map from:@"tt://feed" toSharedViewController:NSClassFromString(@"RssFeedTableViewController")];
     if (![navigator restoreViewControllers]) {
        [navigator openURLAction:[TTURLAction actionWithURLPath:@"tt://root"]];
    }
}

- (BOOL)application:(UIApplication*)application handleOpenURL:(NSURL*)URL {
    [[TTNavigator navigator] openURLAction:[TTURLAction actionWithURLPath:URL.absoluteString]];
    return YES;
}

- (void)dealloc {
    [viewController release];
    [window release];
    [super dealloc];
}

接着就是熟悉的RootViewController,这里生成一个tableview

#import <UIKit/UIKit.h>

@interface MyThree20ProjViewController : TTTableViewController {

}

@end

#import "MyThree20ProjViewController.h"


@implementation MyThree20ProjViewController


- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.title = @"My Three20";
    

    self.dataSource = [TTSectionedDataSource dataSourceWithObjects:
                       @"F",
                       [TTTableTextItem itemWithText:@"feed" URL:@"tt://feed"],
                       nil];
    
}


- (void)dealloc {
    [super dealloc];
}

@end

RssFeedTableViewController,是320中tableViewController的子类,可以通过不同的datasource显示不同的view.

#import <UIKit/UIKit.h>


@interface RssFeedTableViewController : TTTableViewController {

}

@end

#import "RssFeedTableViewController.h"
#import "RssFeedDataSource.h"

@implementation RssFeedTableViewController


- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization.
        self.title = @"Rss";
        self.variableHeightRows = YES;//很重要,否则cell高度无法改变
    }
    return self;
}

- (void)createModel {
    
    self.dataSource = [[[RssFeedDataSource alloc] init] autorelease];
     
}

- (id<UITableViewDelegate>)createDelegate {
    return [[[TTTableViewDragRefreshDelegate alloc] initWithController:self] autorelease];//下拉刷新,但本文未实现
}


- (void)dealloc {
    [super dealloc];
}

@end

我们接着看下RssFeedDataSource,因为我们的tableview不需要section,所以是listdatasource的子类.通过model来获取所需数据,并生成相应的tableItem对象集合

#import <Foundation/Foundation.h>

#import "RssFeedModel.h"

@interface RssFeedDataSource : TTListDataSource {

    RssFeedModel *_feedModel;
}

-(id)initWithQuery:(NSString *)query;
@end

#import "RssFeedDataSource.h"
#import "RssFeedObject.h"

#import "RssTableItem.h"
#import "RssTableItemCell.h"

@implementation RssFeedDataSource

-(id) init 
{
    if (self = [super init])
    {
        _feedModel = [[RssFeedModel alloc] initWithSearchQuery:@"a"];
    }
    
    return self;
}

-(id)initWithQuery:(NSString *)query
{
    if (self = [super init])
    {
        _feedModel = [[RssFeedModel alloc] initWithSearchQuery:query];
    }
    return self;
}

- (void)dealloc 
{
    TT_RELEASE_SAFELY(_feedModel);
    [super dealloc];
}

- (id<TTModel>)model {
    return _feedModel;
}

- (void)tableViewDidLoadModel:(UITableView*)tableView 
{
    NSMutableArray *items = [[NSMutableArray alloc] initWithCapacity:1];
    for (RssFeedObject *rssObj in _feedModel.dataArr)
    {

        
        
        
        RssTableItem *itemObj = [RssTableItem itemWithRssFeedObj:rssObj];

        [items addObject:itemObj];
    }
    
    self.items = items;
    TT_RELEASE_SAFELY(items);
}

///////////////////////////////////////////////////////////////////////////////////////////////////
- (NSString*)titleForLoading:(BOOL)reloading {
    if (reloading) {
        return NSLocalizedString(@"Updating Twitter feed...", @"Twitter feed updating text");
    } else {
        return NSLocalizedString(@"Loading Twitter feed...", @"Twitter feed loading text");
    }
}


///////////////////////////////////////////////////////////////////////////////////////////////////
- (NSString*)titleForEmpty {
    return NSLocalizedString(@"No tweets found.", @"Twitter feed no results");
}


///////////////////////////////////////////////////////////////////////////////////////////////////
- (NSString*)subtitleForError:(NSError*)error {
    return NSLocalizedString(@"Sorry, there was an error loading the Twitter stream.", @"");
}

- (Class)tableView:(UITableView*)tableView cellClassForObject:(id) object {   
    
    if ([object isKindOfClass:[RssTableItem class]]) {  
        return [RssTableItemCell class];  
    } else {  
        return [super tableView:tableView cellClassForObject:object];  
    }  
}  

- (void)tableView:(UITableView*)tableView prepareCell:(UITableViewCell*)cell  
forRowAtIndexPath:(NSIndexPath*)indexPath {  
    cell.accessoryType = UITableViewCellAccessoryDetailDisclosureButton;  
}  


@end

我们再看下model是怎么工作的.因为我们需要请求数据,所以生成TTURLRequestModel的子类,在requestDidFinishLoad:方法解析数据,获得的结果会返回给datasource

#import <Foundation/Foundation.h>


@interface RssFeedModel : TTURLRequestModel {

    NSString *_queryStr;
    
    NSMutableArray *_dataArr;
}

@property (nonatomic, copy)   NSString *queryStr;
@property (nonatomic, retain) NSMutableArray *dataArr;

- (id)initWithSearchQuery:(NSString*)searchQuery;
@end

#import "RssFeedModel.h"
#import "RssFeedObject.h"

#define kID                    @"id"
#define kImArtist            @"im:artist"
#define kLink                @"link"
#define kCategory            @"category"
#define kTitle                @"title"
#define kImContentType        @"im:contentType"
#define kRights                @"rights"
#define kImPrice            @"im:price"
#define kImImage            @"im:image"
#define kImReleaseDate        @"im:releaseDate"
#define kImItemCount        @"im:itemCount"
#define kImName                @"im:name"
#define kUpdated            @"updated"
#define kContent            @"content"

#define KeysArray            nil


#define KEntityName            @"___Entity_Name___"
#define kEntityType            @"___Entity_Type___"
#define kEntityValue        @"___Entity_Value___"

#define kHeight                @"height"
#define kImageHeight        @"60"

#define kRSSFeed  @"http://itunes.apple.com/us/rss/topalbums/limit=10/explicit=true/xml"

@implementation RssFeedModel
@synthesize queryStr = _queryStr, dataArr = _dataArr;

- (id)initWithSearchQuery:(NSString*)searchQuery
{
    if (self = [super init])
    {
        self.queryStr = searchQuery?searchQuery:@"";
        _dataArr = [[NSMutableArray alloc] initWithCapacity:1];
    }
    return self;
}

- (void) dealloc {
    TT_RELEASE_SAFELY(_queryStr);
    TT_RELEASE_SAFELY(_dataArr);
    [super dealloc];
}

- (void)load:(TTURLRequestCachePolicy)cachePolicy more:(BOOL)more
{
    NSString* url = [NSString stringWithFormat:@"%@",kRSSFeed];
    
    TTURLRequest* request = [TTURLRequest
                             requestWithURL: url
                             delegate: self];
    
    request.cachePolicy = cachePolicy;
    request.cacheExpirationAge = TT_CACHE_EXPIRATION_AGE_NEVER;
    TTURLXMLResponse* response = [[TTURLXMLResponse alloc] init];
    response.isRssFeed = YES;
    request.response = response;
    TT_RELEASE_SAFELY(response);
    
    [request send];
}




- (void)requestDidFinishLoad:(TTURLRequest*)request 
{
    
//    [NSArray arrayWithObjects:kID,kImArtist,kLink,kCategory,kTitle,kImContentType
    TTURLXMLResponse *xmlResponse = request.response;
    
    NSDictionary *feed = xmlResponse.rootObject;
    
    NSArray *allKey = [feed allKeys];
    
    NSMutableArray *mArr = [NSMutableArray arrayWithCapacity:1];
    for (NSString *str in allKey)
    {
        NSLog(@"%@\n",str);
        [mArr addObject:[feed objectForKey:str]];
    }
    NSArray *entry = [feed objectForKey:@"entry"];//rss feed：每个是一个dictionary代表一行
    
    
    
    for(NSDictionary *item in entry)
    {
        RssFeedObject *obj = [[RssFeedObject alloc] init];
        
        for( NSString *str in [item allKeys])
        {
            id attr = [item valueForKey:str];
            if ([attr isKindOfClass:[NSDictionary class]])
            {
                
                NSArray *attrKeys = [attr allKeys];
                
                NSString *entityName = [(NSDictionary *)attr valueForKey:KEntityName];
                if ([entityName isEqualToString:kID])
                {
                    obj.readMore = [(NSDictionary *)attr valueForKey:kEntityValue];
                    
                }
                
                else if ([entityName isEqualToString:kImArtist])
                {
                    obj.artist = [(NSDictionary *)attr valueForKey:kEntityValue];
                    
                }
                
                else if ([entityName isEqualToString:kCategory])
                {
                    obj.genre = [(NSDictionary *)attr valueForKey:@"label"];
                    
                }
                
                else if ([entityName isEqualToString:kTitle])
                {
                    obj.header = [(NSDictionary *)attr valueForKey:kEntityValue];
                    
                }
                
                else if ([entityName isEqualToString:kRights])
                {
                    obj.copyRight = [(NSDictionary *)attr valueForKey:kEntityValue];
                    
                }
                
                else if ([entityName isEqualToString:kImPrice])
                {
                    obj.price = [(NSDictionary *)attr valueForKey:kEntityValue];
                    
                }
                
                
                else if ([entityName isEqualToString:kImReleaseDate])
                {
                    obj.releaseDate = [(NSDictionary *)attr valueForKey:kEntityValue];
                    
                }
                
                
                else if ([entityName isEqualToString:kImItemCount])
                {
                    obj.itemCount = [(NSDictionary *)attr valueForKey:kEntityValue];
                    
                }
                
                
                else if ([entityName isEqualToString:kImName])
                {
                    obj.title = [(NSDictionary *)attr valueForKey:kEntityValue];
                    
                }
                
                
                else if ([entityName isEqualToString:kUpdated])
                {
                    obj.updateDate = [(NSDictionary *)attr valueForKey:kEntityValue];
                    
                }
                else {
                    
                }

            }
            
            else if ([attr isKindOfClass:[NSArray class]])
            {
                for (NSDictionary *imagDic in attr)
                {
                    NSString *height = [imagDic valueForKey:kHeight];
                    if ([height isEqualToString:kImageHeight]) 
                    {
                        obj.imageLink = [imagDic valueForKey:kEntityValue];
                    }
                }
            }
            
        }
        
        [self.dataArr addObject:obj];
        TT_RELEASE_SAFELY(obj);
    }
        
    NSDictionary *item = [entry objectAtIndex:0];
    
    NSArray *itemKeys = [item allKeys];
    NSMutableArray *itemContent = [NSMutableArray arrayWithCapacity:1];
    for(NSString *str in itemKeys)
    {
        [itemContent addObject:[item objectForKey:str]];
        NSLog(@"%@:%@\n",str,[item objectForKey:str]);
    }
    
    
    
    NSLog(@"%@",feed);
    
    [super requestDidFinishLoad:request];//important
}
@end

tableItemCell就是自定义的cell,tableItem是tableviewcell所代表的object,在cell中需要将object与view(就是cell)联系起来.在这里我们也可以体会到MVC在iOS中真的是无处不在.

#import <Foundation/Foundation.h>

@class RssFeedObject;

@interface RssTableItem : TTTableItem
{
    NSString *_artist;
    NSString *_title;
    NSString *_link;
    NSString *_imageName;
}

@property (nonatomic, copy)  NSString *artist;
@property (nonatomic, copy)  NSString *title;
@property (nonatomic, copy)  NSString *link;
@property (nonatomic, copy)  NSString *imageName;

+(id)itemWithRssFeedObj:(RssFeedObject *)obj;

-(id)initWithRssFeedObj:(RssFeedObject *)obj;
@end

#import "RssTableItem.h"
#import "RssFeedObject.h"

@implementation RssTableItem
@synthesize artist = _artist, title = _title,link = _link,imageName = _imageName;

- (id)init
{
    if (self = [super init])
    {
        _artist = nil;
        _title = nil;
        _link = nil;
        _imageName = nil;
    }
    return self;
}

+(id)itemWithRssFeedObj:(RssFeedObject *)obj
{
    RssTableItem *item = [[[RssTableItem alloc] init] autorelease];
    item.artist = obj.artist;
    item.title = obj.title;
    item.link = obj.readMore;
    item.imageName = obj.imageLink;
    
    return item;
    
}

-(id)initWithRssFeedObj:(RssFeedObject *)obj
{
    if (self = [[RssTableItem alloc] init])
    {
        self.artist = obj.artist;
        self.title = obj.title;
        self.link = obj.readMore;
        self.imageName = obj.imageLink;
    }
    
    return self;
}

- (void)dealloc
{
    TT_RELEASE_SAFELY(_artist);
    TT_RELEASE_SAFELY(_title);
    TT_RELEASE_SAFELY(_title);
    TT_RELEASE_SAFELY(_imageName);
    [super dealloc];
}

@end

#import <Foundation/Foundation.h>


@interface RssTableItemCell : TTTableViewCell {
    UILabel *_artistLab;
    UILabel *_titleLab;
    TTImageView *_myImageView;
}

@end


#import "RssTableItemCell.h"
#import "RssTableItem.h"

@implementation RssTableItemCell
+ (CGFloat)tableView:(UITableView*)tableView rowHeightForObject:(id)object 
{
    return 60;
}

- (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString*)identifier  
{
    if (self = [super initWithStyle:style reuseIdentifier:identifier])
    {
        _myImageView = [[TTImageView alloc] initWithFrame:CGRectMake(5, 0, 60, 60)];
        [self.contentView addSubview:_myImageView];
        
        _artistLab = [[UILabel alloc] initWithFrame:CGRectMake(70, 10, 200, 10)];
        _artistLab.textColor = [UIColor grayColor];
        _artistLab.backgroundColor = [UIColor clearColor];
        [self.contentView addSubview:_artistLab];
        
        
        _titleLab = [[UILabel alloc] initWithFrame:CGRectMake(70, 30, 200, 20)];
        _titleLab.textColor = [UIColor grayColor];
        _titleLab.backgroundColor = [UIColor clearColor];
        [self.contentView addSubview:_titleLab];
        
    }
    return self;
}

- (void)dealloc
{
    TT_RELEASE_SAFELY(_artistLab);
    TT_RELEASE_SAFELY(_myImageView);
    TT_RELEASE_SAFELY(_titleLab);
    [super dealloc];
}


- (void)layoutSubviews
{
    [super layoutSubviews];
    
}

- (id)object
{
    return self;;
}

- (void)setObject:(id)obj
{
    if (self != obj)
    {
        [super setObject:obj];
        RssTableItem *item = obj;
        
        _myImageView.urlPath = item.imageName;
        _artistLab.text = item.artist;
        _titleLab.text = item.title;
    }
}


@end

最后是一个解析数据的对象模型RssFeedObject.

#import <Foundation/Foundation.h>


@interface RssFeedObject : NSObject {
    NSString *_header;
    NSString *_title;
    NSString *_artist;
    NSString *_genre;
    NSString *_price;
    NSString *_releaseDate;
    NSString *_copyRight;
    NSString *_readMore;
    
    NSString *_itemCount;
    NSString *_imageLink;
    NSString *_updateDate;
}

@property (nonatomic, copy) NSString *header,*title,*artist,*genre;
@property (nonatomic, copy) NSString *price,*releaseDate,*copyRight,*readMore;
@property (nonatomic, copy) NSString *itemCount,*imageLink,*updateDate;


@end

#import "RssFeedObject.h"


@implementation RssFeedObject
@synthesize header=_header,title=_title,artist=_artist,genre=_genre;

@synthesize price=_price,releaseDate=_releaseDate,copyRight=_copyRight,readMore=_readMore;

@synthesize itemCount = _itemCount,imageLink = _imageLink,updateDate = _updateDate;
- (void)dealloc
{
    TT_RELEASE_SAFELY(_header);
    TT_RELEASE_SAFELY(_title);
    TT_RELEASE_SAFELY(_artist);
    TT_RELEASE_SAFELY(_genre);
    TT_RELEASE_SAFELY(_price);
    TT_RELEASE_SAFELY(_releaseDate);
    TT_RELEASE_SAFELY(_copyRight);
    TT_RELEASE_SAFELY(_readMore);
    
    TT_RELEASE_SAFELY(_itemCount);
    TT_RELEASE_SAFELY(_imageLink);
    TT_RELEASE_SAFELY(_updateDate);
    [super dealloc];
}
@end

至此我们的工程就完成了.程序的大致流程如图3所示,具体的代码细节都是很容易理解的.如果有写的不明白或者错误的地方请多多指正.

谢谢.

ps:有谁知道mac下有没有啥好的博客客户端啊,不然家里都打不开,只能到公司里抽时间写