如何处理Firebase离线模式和数据推送?-HowdealwithFirebaseofflinemodeanddatapush?

When using Firebase, it is recommanded to use the push() command to manage data list. That's really fine, it provides a unique and ordered id for data pushed on the list.

在使用Firebase时，将命令使用push()命令管理数据列表。这真的很好，它为列表上推送的数据提供了一个惟一的和有序的id。

However, when Firebase goes offline (goOffline or NetworkOffline), if the app try to push a data on a list, the completion listener is not triggered, until the app goes back online : so there is no unique id until the line is on again.

但是，当Firebase脱机(goOffline或NetworkOffline)时，如果应用程序试图将数据推到列表上，那么完成监听器就不会被触发，直到该应用程序返回到在线状态:因此，直到这条线再次出现，才会有唯一的id。

1/ Is that the expected/normal behavior ?

这是期望/正常的行为吗?

2/ I didn"t see in the document (as far I remember), that the push command is working differently (or only in onlinemode) in offline state. Did I miss a line somewhere ?

2/我在文档中没有看到(据我所知)，push命令在脱机状态下工作方式不同(或仅在onlinemode中)。我是不是在什么地方漏了一条线?

3/ My use case deal with data that own relationship. It means I want create an object (kind of master) in a list, and then reuse this master object id (provided by the completion listener) to build the relation between the master object and all other relevants objects. How may I deal with this offline state ?

3/我的用例处理与自己相关的数据。这意味着我想在列表中创建一个对象(某种主对象)，然后重用这个主对象id(由完成侦听器提供)来构建主对象和所有其他相关对象之间的关系。我如何处理这种脱机状态?

Code Example :

代码示例:

    findViewById(R.id.button3).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            new Firebase(getString(R.string.firebase_url)).child("stack").push().setValue(counter++, new Firebase.CompletionListener() {
                @Override
                public void onComplete(FirebaseError firebaseError, Firebase firebase) {
                    ((TextView) findViewById(R.id.textView3)).setText(String.valueOf(counter) + " - " + firebase.toString());
                }

            });
        }
    });

Edit

编辑

Here is 4 ways to add data:

这里有四种添加数据的方法:

Push with Listener

推动与侦听器

   findViewById(R.id.button3).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            new Firebase(getString(R.string.firebase_url)).child("stack").push().setValue(counter++, new Firebase.CompletionListener() {
                @Override
                public void onComplete(FirebaseError firebaseError, Firebase firebase) {
                    ((TextView) findViewById(R.id.textView3)).setText(String.valueOf(counter) + " - " + firebase.toString());
                }

            });
        }
    });

SetValue with Listener

SetValue与侦听器

    findViewById(R.id.button4).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            new Firebase(getString(R.string.firebase_url)).child("stackManual").child(UUID.randomUUID().toString()).setValue(counter++, new Firebase.CompletionListener() {
                @Override
                public void onComplete(FirebaseError firebaseError, Firebase firebase) {
                    ((TextView) findViewById(R.id.textView4)).setText(String.valueOf(counter) + " - " + firebase.toString());
                }

            });
        }
    });

SetValue without Listener

SetValue没有监听器

    findViewById(R.id.button5).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Firebase temp = new Firebase(getString(R.string.firebase_url)).child("stackManual").child(UUID.randomUUID().toString());
            temp.setValue(counter++);


            ((TextView) findViewById(R.id.textView5)).setText(String.valueOf(counter) + " - " + temp.getKey().toString());
        }

    });

Push without Listener

推动没有监听器

    findViewById(R.id.button6).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Firebase temp = new Firebase(getString(R.string.firebase_url)).child("stack").push();
            temp.setValue(counter++);

            ((TextView) findViewById(R.id.textView6)).setText(String.valueOf(counter) + " - " + temp.getKey().toString());
        }

    });

IT APPEAR THAT THE LISTENERS ARE TRIGGERED ONLY WHEN THE DATA ARE IN THE DATABASE ON THE SERVER, AND NOT ON THE LOCAL DB ! - IS THAT CORRECT ? - IS THAT DOCUMENTED ?

似乎只有在服务器上的数据库中而不是本地数据库中，才会触发侦听器!-对吗?-有文件证明吗?

Because knowing that, a straight forward asynchronous application is more difficult to build now : encapsulation of asynchronous job may not be performed if offline, may it ?

因为知道了这一点，现在就很难构建一个直接向前的异步应用程序:如果脱机，异步作业的封装可能不会被执行，是吗?

2 个解决方案

Firebase ref = new Firebase(getString(R.string.firebase_url));
Firebase newStackRef = ref.child("stack").push();
System.out.println("New key/push id: "+newStackRef.key());
newStackRef.setValue(counter++, new Firebase.CompletionListener() {