Question

我目前正在尝试使用firebase在我的应用中实现简单的聊天服务。我按照教程here

进行了操作

我没有收到错误，但由于某些未知原因，我无法在列表视图中看到聊天消息。这是我的代码：

MainActivity.java

private FirebaseListAdapter<ChatMessage> adapter;

private final int SIGN_IN_REQUEST_CODE = 123;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    FirebaseApp.initializeApp(this);
    if(FirebaseAuth.getInstance().getCurrentUser() == null) {
        // Start sign in/sign up activity
        startActivityForResult(
                AuthUI.getInstance()
                        .createSignInIntentBuilder()
                        .build(),
                SIGN_IN_REQUEST_CODE
        );
    } else {
        // User is already signed in. Therefore, display
        // a welcome Toast
        Toast.makeText(this,
                "Welcome " + FirebaseAuth.getInstance()
                        .getCurrentUser()
                        .getDisplayName(),
                Toast.LENGTH_LONG)
                .show();

        // Load chat room contents
        displayChatMessages();
    }

    FloatingActionButton fab =
            (FloatingActionButton)findViewById(R.id.fab);

    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            EditText input = (EditText)findViewById(R.id.input);

            // Read the input field and push a new instance
            // of ChatMessage to the Firebase database
            FirebaseDatabase.getInstance()
                    .getReference()
                    .push()
                    .setValue(new ChatMessage(input.getText().toString(),
                            FirebaseAuth.getInstance()
                                    .getCurrentUser()
                                    .getDisplayName())
                    );

            // Clear the input
            input.setText("");
        }
    });
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if(requestCode == SIGN_IN_REQUEST_CODE) {
        if(resultCode == RESULT_OK) {
            Toast.makeText(this,
                    "Successfully signed in. Welcome!",
                    Toast.LENGTH_LONG)
                    .show();
            displayChatMessages();
        } else {
            Toast.makeText(this,
                    "We couldn't sign you in. Please try again later.",
                    Toast.LENGTH_LONG)
                    .show();

            // Close the app
            finish();
        }
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.main_menu, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    if(item.getItemId() == R.id.menu_sign_out) {
        AuthUI.getInstance().signOut(this)
                .addOnCompleteListener(new OnCompleteListener<Void>() {
                    @Override
                    public void onComplete(@NonNull Task<Void> task) {
                        Toast.makeText(MainActivity.this,
                                "You have been signed out.",
                                Toast.LENGTH_LONG)
                                .show();

                        // Close activity
                        finish();
                    }
                });
    }
    return true;
}

private void displayChatMessages() {
    ListView listOfMessages = (ListView)findViewById(R.id.list_of_messages);

    adapter = new FirebaseListAdapter<ChatMessage>(this, ChatMessage.class,
            R.layout.message, FirebaseDatabase.getInstance().getReference()) {
        @Override
        protected void populateView(View v, ChatMessage model, int position) {
            // Get references to the views of message.xml
            TextView messageText = (TextView)v.findViewById(R.id.message_text);
            TextView messageUser = (TextView)v.findViewById(R.id.message_user);
            TextView messageTime = (TextView)v.findViewById(R.id.message_time);

            // Set their text
            messageText.setText(model.getMessageText());
            messageUser.setText(model.getMessageUser());

            // Format the date before showing it
            messageTime.setText(DateFormat.format("dd-MM-yyyy (HH:mm:ss)",
                    model.getMessageTime()));
        }
    };

    listOfMessages.setAdapter(adapter);
}

模块：的build.gradle

    dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.android.support:appcompat-v7:25.3.1'
    compile 'com.android.support:design:25.3.1'
    compile 'com.firebaseui:firebase-ui:1.2.0'
    compile 'com.google.firebase:firebase-core:10.2.0'
    compile 'com.google.firebase:firebase-database:10.2.0'
    compile 'com.google.firebase:firebase-storage:10.2.0'
    compile 'com.google.firebase:firebase-crash:10.2.0'
    compile 'com.google.firebase:firebase-auth:10.2.0'
    compile 'com.google.firebase:firebase-messaging:10.2.0'
    testCompile 'junit:junit:4.12'
}

apply plugin: 'com.google.gms.google-services'

正如我在使用我的消息的值放入populateView中的日志之后建议的那样奇怪地只显示我在firebase数据库中的前两个消息但反复出现。（我的firebase中有14条消息，有2个不同的用户）

05-25 15：23：51.470 12946-12946 /？ D / asd：jahshss 05-25 15：23：51.470 12946-12946 /？ D / asd：fhci 05-25 15：23：51.470 12946-12946 /？ D / asd：jahshss 05-25 15：23：51.470 12946-12946 /？ D / asd：fhci 05-25 15：23：51.500 12946-12946 /？ D / asd：jahshss 05-25 15：23：51.500 12946-12946 /？ D / asd：fhci 05-25 15：23：51.510 12946-12946 /？ D / asd：jahshss 05-25 15：23：51.510 12946-12946 /？ D / asd：jahshss 05-25 15：23：51.590 12946-13127 /？ D / FA：连接到远程服务 05-25 15：23：51.680 12946-12946 /？ D / asd：jahshss 05-25 15：23：51.690 12946-12946 /？ D / asd：jahshss 05-25 15：23：51.690 12946-12946 /？ D / asd：fhci 05-25 15：23：51.690 12946-12946 /？ D / asd：jahshss 05-25 15：23：51.700 12946-12946 /？ D / asd：fhci

jahshss是我的第一个消息值，fhci是我在firebase数据库中的第二个消息值。

Firebase无法收到聊天消息

0 个答案: