Question

我已经设置了一个委托方法，可以从我的masterViewController到我的detailViewController进行通信，但委托方法没有被调用。

MasterViewController.h

#import <UIKit/UIKit.h>

@class DetailViewController;
@class MasterViewController;

@protocol MasterViewControllerDelegate
- (void)SelectionChanged:(NSString *)url;
@end

@interface MasterViewController : UITableViewController

@property (nonatomic, weak) id<MasterViewControllerDelegate> delegate;
@property (strong, nonatomic) DetailViewController *detailViewController;

@end

然后在我的MasterViewController.m中我正在合成委托：

@synthesize delegate;

最后我从didSelectRowAtIndexPath方法调用委托方法，如下所示：

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    NSArray *links = [NSArray arrayWithObjects:
                      @"http://www.link1.com",
                      @"http://www.link2.com",
                      @"http://www.link3.com",
                      nil];

   [self.delegate SelectionChanged:[links objectAtIndex: indexPath.row]];
}

然后在我的DetailViewController.h中我有：

@interface DetailViewController : UIViewController <UISplitViewControllerDelegate, MasterViewControllerDelegate>

在DetailViewController.m中：

- (void)SelectionChanged:(NSString *)url {
    NSLog(@"URL is %@", url);
}

当我运行应用时，来自NSLog的{{1}}永远不会被调用，我没有错误。有什么想法吗？

Answer 1

好的，我想通了......在我的AppDelegate.m文件中，我将以下内容添加到didFinishLaunchingWithOptions

DetailViewController *detail = (DetailViewController *)navigationController.topViewController;
UINavigationController *masterNavigationController = [splitViewController.viewControllers objectAtIndex:0];
MasterViewController *master = (MasterViewController *)masterNavigationController.topViewController;

NSLog(@"%@",masterNavigationController.topViewController);
master.delegate = detail;

所以整个方法看起来像这样：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    // Override point for customization after application launch.
    UISplitViewController *splitViewController = (UISplitViewController *)self.window.rootViewController;
    UINavigationController *navigationController = [splitViewController.viewControllers lastObject];
    splitViewController.delegate = (id)navigationController.topViewController;

    DetailViewController *detail = (DetailViewController *)navigationController.topViewController;
    UINavigationController *masterNavigationController = [splitViewController.viewControllers objectAtIndex:0];
    MasterViewController *master = (MasterViewController *)masterNavigationController.topViewController;

    NSLog(@"%@",masterNavigationController.topViewController);
    master.delegate = detail;

    return YES;
}

基本上问题是我没有在任何地方分配代表......呃。

UISplitView中的委托未被调用

1 个答案: