ios - 如何在多个ViewController之间共享数据？

我知道共享数据的一种方法是segue。但是在我的应用程序中，我有多个选项卡，其中包含许多VC。例如userName和address。我想在某些VC中显示这些信息。
每次我查询云都不正确。我正在遵循这个答案的第一部分:answer。但是作为一个新手，我不确定如何定义MyDataModel。它是NSObject类吗？如果有人可以用两个NSString字段将此类定义为示例，我将不胜感激。以及如何在VC和AppDelegate中访问这些字段。

内部AppDelegate

@interface MyAppDelegate : NSObject <UIApplicationDelegate, UITabBarControllerDelegate>
{

    MyDataModel *model;
    AViewController *aViewController;
    BViewController *bViewController;
    ...
}

@property (retain) IBOutlet AViewController *aViewController;
@property (retain) IBOutlet BViewController *aViewController;

@end

@implementation MyAppDelegate

...

- (void)applicationDidFinishLaunching:(UIApplication *)application
{
...

    aViewController.model = model;

    bViewController.model = model;

    [window addSubview:tabBarController.view];
    [window makeKeyAndVisible];
}

内部VC:

@interface AViewController : UIViewController {
    MyDataModel *model;
}

@property (nonatomic, retain) MyDataModel *model;

@end

@interface BViewController : UIViewController {
    MyDataModel *model;
}

@property (nonatomic, retain) MyDataModel *model;

@end

我唯一需要的是在哪里定义MyDataMode以及如何访问其字段？

最佳答案

您可以使用单例类，

----------
SharedManages.h
----------

#import <Foundation/Foundation.h>
#import "Reachability.h"
#import "Reachability.h"

@interface SharedManager : NSObject
{

}
+(SharedManager *)sharedInstance;

// Create property of your object which you want to access from whole over project.

@property (retain, nonatomic) User *loginUser;
@property (assign, readwrite) BOOL isNetAvailable;

@end

----------

----------
SharedManages.m
----------

#import "SharedManager.h"

static SharedManager *objSharedManager;

@implementation SharedManager

@synthesize
isNetAvailable  = _isNetAvailable,
loginUser    = _ loginUser;

+(SharedManager *)sharedInstance
{
    if(objSharedManager == nil)
    {
        objSharedManager = [[SharedManager alloc] init];
        objSharedManager. loginUser = [User alloc]] init];

        Reachability *r = [Reachability reachabilityForInternetConnection];
        NetworkStatus internetStatus = [r currentReachabilityStatus];
        // Bool

        if(internetStatus == NotReachable)
        {
            NSLog(@"Internet Disconnected");
            objSharedManager.isNetAvailable = NO;  // Internet not Connected
        }
        else if (internetStatus == ReachableViaWiFi)
        {
            NSLog(@"Connected via WIFI");
            objSharedManager.isNetAvailable = YES; // Connected via WIFI
        }
        else if (internetStatus == ReachableViaWWAN)
        {
            NSLog(@"Connected via WWAN");
            objSharedManager.isNetAvailable = YES; // Connected via WWAN
        }

    }

    return objSharedManager;
}


@end

从其他 class 访问...

[SharedManager sharedInstance].isNetAvailable ;

[SharedManager sharedInstance].loginUser ;

希望这个能对您有所帮助..

vc

ios - 如何在多个ViewController之间共享数据？