UITableViewDataSource實現的方法，不叫

Question

我試圖以編程方式創建UITableView，但它讓我迷惑，因爲UITableViewDataSource的協議的實現方法永遠不會被調用

的ViewController

@interface viewController : UIViewController <UITableViewDataSource> 
@end 

#import "viewController.h" 

@interface viewController() 
@property (strong, nonatomic) NSArray *tweetsArray; 
@end 

@implementation viewController { 
    UITableView *tableView; 
} 

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 
    // Do any additional setup after loading the view. 
    self.tweetsArray = [[NSArray alloc] initWithObjects: 
         @"This is the first line", 
         @"This is the second line", 
         @"This is the third line", 
         @"This is the fourth line", 
         @"This is the fifth line", 
         nil]; 

    tableView = [[UITableView alloc] initWithFrame:self.view.bounds style:UITableViewStylePlain]; 

    tableView.dataSource = self; 

    [self.view addSubview:tableView]; 
} 

-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section 
{ 
    return [self.tweetsArray count]; 
} 

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath 
{ 
    static NSString *cellIdentifier = @"SettingsCell"; 
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier]; 

    if (cell == nil) 
    { 
     cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellIdentifier]; 
    } 

    NSString *tweet = [self.tweetsArray objectAtIndex:indexPath.row]; 
    [cell.textLabel setText:@"Via Cuong Doan"]; 
    [cell.detailTextLabel setText:tweet]; 

    return cell; 
}  
@end 

的AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions 
{ 
    // Override point for customization after application launch. 
    viewController *view = [[viewController alloc] init]; 
    [self.window addSubview:view.view]; 
    return YES; 
} 

一切看起來正常，但-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section和-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath永遠不會叫

Answer 1

您需要didFinishLaunchingWithOptions創建的窗口，你也不要手動控制器的視圖添加到窗口，你應該控制窗口的根視圖控制器，

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { 
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]; 
    ViewController *view = [[ViewController alloc] init]; 
    self.window.rootViewController = view; 
    [self.window makeKeyAndVisible]; 
    return YES; 
} 

Answer 2

你嘗試：

@interface viewController : UIViewController <UITableViewDataSource, UITableViewDelegate> 

在第一線？

Answer 3

添加以下內容：

tableView.delegate = self;