StoryBoard学习（6）：使用notification广播实现视图跳转传递数据

转载自  http://blog.csdn.net/mad1989/article/details/7919504

广播机制分为：注册----发送------------接收(接收方)，具体请看一下代码。

1，在要发送数据的视图页面.m文件处理发送逻辑的方法里注册+发送

- (IBAction)pressed:(id)sender {
    
//    [self performSegueWithIdentifier:@"second" sender:self];
    NSLog(@"send message:%@",firstField.text);

    
    
    //页面跳转传值方法二：利用notification
    NSDictionary *dicts = [NSDictionary dictionaryWithObjectsAndKeys:@"one1",@"one",@"two2",@"two",@"three3",@"three", nil];
    //注册(第一步)
    NSNotification *notification  =[NSNotification notificationWithName:@"mynotification" object:firstField.text];
    //发送（第二步）
    [[NSNotificationCenter defaultCenter] postNotification:notification];
    
    //注册+发送也可以一行完成(等效于以上两行)
    [[NSNotificationCenter defaultCenter] postNotificationName:@"mynotification2" object:dicts];//发送一个字典过去


}

notificationWithName:参数的值是自己定义，接收方以此名称为接收标识。

2，在跳转后，接收数据视图页面.m文件中处理逻辑的方法里 接收

- (void)viewDidLoad
{
    [super viewDidLoad];
	// Do any additional setup after loading the view.
    
    //接受端：接受（第一步）
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(notificationHandler:) name:@"mynotification" object:nil];
    
    
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(notificationHandler2:) name:@"mynotification2" object:nil];

}

//自定义接收信息和处理的方法（第二步）
-(void) notificationHandler:(NSNotification *) notification{
    
    secondField.text = [notification object];//收到消息后在UItextField中显示出来

}
//自定义接收字典信息的方法
-(void) notificationHandler2:(NSNotification *) notification2{

    NSDictionary *dict = [notification2 object];
     NSLog(@"receive dict :%@,forkey:%@",dict,[dict objectForKey:@"one"]);

}

注意：如果注册的notification在目标视图没有收到或名称写错，目标视图的相关方法就不会执行

    private void installNormal() {
        LogUtils.log(TAG, LogUtils.getThreadName());
        setStatus(State.INSTALLING);
        String rootpath = Environment.getExternalStorageDirectory().getPath()
                + File.separator + Environment.DIRECTORY_DOWNLOADS + File.separator;
        Uri uri = Uri.fromFile(new File(rootpath + downloadFileName));
        LogUtils.log(TAG, LogUtils.getThreadName() + "uri = " + uri);
        Intent intent = new Intent();
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        intent.setAction(Intent.ACTION_VIEW);
        intent.setDataAndType(uri, "application/vnd.android.package-archive");
        mContext.startActivity(intent);

    }

NSURL *url = [NSURL URLWithString: urlString ];

    
ASIFormDataRequest *request = [ASIFormDataRequest requestWithURL:url];
NSMutableData *postData = [NSMutableData dataWithContentsOfFile:imagePath];  
  
[request setPostBodyFilePath:imagePath];

[request setRequestMethod:@"POST"];
[request startSynchronous];