java - 无法解析符号 FirebaseListAdapter

Question

如何正确插入 FirebaseListAdapter？我总是收到错误“无法解析 FirebaseListAdapter”。如果你需要什么，我会发布它。整个应该是用聊天消息。错误在第 26 行输出。

我的代码:

import android.content.Intent;
import android.support.annotation.NonNull;
import android.support.design.widget.FloatingActionButton;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.format.DateFormat;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import com.firebase.ui.auth.AuthUI;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.FirebaseDatabase;


public class Chat extends AppCompatActivity {
    private FirebaseAuth mAuth;
    private static final int SIGN_IN_REQUEST_CODE = 123;
    private FirebaseListAdapter<ChatMessage> adapter; //here is the problem

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


        mAuth = FirebaseAuth.getInstance();

        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,
                    "Willkommen " + 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
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, 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(Chat.this,
                                    "You have been signed out.",
                                    Toast.LENGTH_LONG)
                                    .show();

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


    @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,
                        "Erfolgreich eingeloggt. Willkommen!",
                        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 void onStart() {
        super.onStart();

    }

    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);
    }
}

构建 Gradle

android {
    compileSdkVersion 26
    buildToolsVersion "26.0.2"
    defaultConfig {
        applicationId "de.bluestarfish.bluestarfish"
        minSdkVersion 16
        targetSdkVersion 26
        versionCode 3
        versionName "0.3.2"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation 'com.android.support.constraint:constraint-layout:1.0.2'
    compile fileTree(include: ['*.jar'], dir: 'libs')
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })


    compile 'com.android.support:appcompat-v7:26.1.0'
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:design:26.1.0'
    compile 'com.android.support:cardview-v7:26.1.0'
    compile 'com.daimajia.easing:library:2.0@aar'
    compile 'com.daimajia.androidanimations:library:2.3@aar'
    compile 'com.squareup.picasso:picasso:2.5.2'
    compile 'com.google.android.gms:play-services-ads:11.8.0'
    compile 'com.google.firebase:firebase-messaging:11.8.0'
    compile 'com.google.firebase:firebase-core:11.8.0'
    compile 'com.google.firebase:firebase-ads:11.8.0'
    compile 'com.google.firebase:firebase-auth:11.8.0'
    compile 'com.firebaseui:firebase-ui-auth:3.2.1'
    compile 'com.google.firebase:firebase-database:11.8.0'

}

// Add to the bottom of the file
apply plugin: 'com.google.gms.google-services'

Answer 1

适配器的构造函数在 3.x 版本中已更改。请关注instructions from the FirebaseUI documentation :

FirebaseListOptions<Chat> options = new FirebaseListOptions.Builder<Chat>()
        .setQuery(query, Chat.class)
        .build();

FirebaseListAdapter<Chat> adapter = new FirebaseListAdapter<Chat>(options) {
    @Override
    protected void populateView(View v, Chat model, int position) {
        // Bind the Chat to the view
        // ...
    }
};