我创建了一个基本的反馈app，其中主activity(mainactivity.java)以imageViews的形式记录客户的姓名和评级（1-5），并将数据发送到FireBase。

我的第二个activity(score.java)只是汇总来自FireBase中所有客户的评级。

我的问题是应用程序在启动时直接跳转到score.java，而不收集来自客户的反馈。 附注。 我使用intent在活动之间跳转。

下面是代码:

主要活动-

package com.example.feedback;

import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;    
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;
import static android.os.SystemClock.sleep;

public class MainActivity extends AppCompatActivity {

    EditText name;
    ImageView oneStar, twoStar, threeStar, fourStar, fiveStar;
    Intent intent;
    FirebaseDatabase rootNode;
    DatabaseReference reference;

    public void displayScore() {
        intent = new Intent(getApplicationContext(), Score.class);
        startActivity(intent);
    }
   
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE); //will hide the title
        getSupportActionBar().hide(); // hide the title bar
        this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN); //enable full screen
        setContentView(R.layout.activity_main);
        name =  findViewById(R.id.editTextPersonName);
        oneStar =  findViewById(R.id.imageView1);
        twoStar =  findViewById(R.id.imageView2);
        threeStar = findViewById(R.id.imageView3);
        fourStar =  findViewById(R.id.imageView4);
        fiveStar =  findViewById(R.id.imageView5);
        oneStar.setTag(1);
        twoStar.setTag(2);
        threeStar.setTag(3);
        fourStar.setTag(4);
        fiveStar.setTag(5);

        oneStar.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (name.length() == 0){
                    name.setError("Please enter your full name.");
                }
                else {
                    name.setError(null);
                    rootNode = FirebaseDatabase.getInstance();
                    reference = rootNode.getReference().child("Users");
                    //Fetch all values
                    String username = name.getText().toString();
                    String value = view.getTag().toString();
                    int rating = Integer.parseInt(value);
                    UserHelper helper = new UserHelper(username,rating);
                    reference.child(username).setValue(helper);
                    Toast.makeText(MainActivity.this, "Feedback submitted successfully!", Toast.LENGTH_SHORT).show();
                    sleep(200);
                    displayScore();
                }
            }
        });

        twoStar.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (name.length() == 0){
                    name.setError("Please enter your full name.");
                }
                else {
                    name.setError(null);
                    rootNode = FirebaseDatabase.getInstance();
                    reference = rootNode.getReference().child("Users");
                    //Fetch all values
                    String username = name.getText().toString();
                    String value = view.getTag().toString();
                    int rating = Integer.parseInt(value);
                    UserHelper helper = new UserHelper(username,rating);
                    reference.child(username).setValue(helper);
                    Toast.makeText(MainActivity.this, "Feedback submitted successfully!", Toast.LENGTH_SHORT).show();
                    displayScore();
                }
            }
        });

        threeStar.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (name.length() == 0){
                    name.setError("Please enter your full name.");
                }
                else {
                    name.setError(null);
                    rootNode = FirebaseDatabase.getInstance();
                    reference = rootNode.getReference().child("Users");
                    //Fetch all values
                    String username = name.getText().toString();
                    String value = view.getTag().toString();
                    int rating = Integer.parseInt(value);
                    UserHelper helper = new UserHelper(username,rating);
                    reference.child(username).setValue(helper);
                    Toast.makeText(MainActivity.this, "Feedback submitted successfully!", Toast.LENGTH_SHORT).show();
                    displayScore();
                }
            }
        });

        fourStar.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (name.length() == 0){
                    name.setError("Please enter your full name.");
                }
                else {
                    name.setError(null);
                    rootNode = FirebaseDatabase.getInstance();
                    reference = rootNode.getReference().child("Users");
                    //Fetch all values
                    String username = name.getText().toString();
                    String value = view.getTag().toString();
                    int rating = Integer.parseInt(value);
                    UserHelper helper = new UserHelper(username,rating);
                    reference.child(username).setValue(helper);
                    Toast.makeText(MainActivity.this, "Feedback submitted successfully!", Toast.LENGTH_SHORT).show();
                    displayScore();
                }
            }
        });

        fiveStar.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (name.length() == 0){
                    name.setError("Please enter your full name.");
                }
                else {
                    name.setError(null);
                    rootNode = FirebaseDatabase.getInstance();
                    reference = rootNode.getReference().child("Users");
                    //Fetch all values
                    String username = name.getText().toString();
                    String value = view.getTag().toString();
                    int rating = Integer.parseInt(value);
                    UserHelper helper = new UserHelper(username,rating);
                    reference.child(username).setValue(helper);
                    Toast.makeText(MainActivity.this, "Feedback submitted successfully!", Toast.LENGTH_SHORT).show();
                    displayScore();
                }
            }
        });
    }
}

记分。java-

package com.example.feedback;
import android.os.Bundle;
import android.view.Window;
import android.view.WindowManager;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.annotation.StringRes;
import androidx.appcompat.app.AppCompatActivity;

import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;

public class Score extends AppCompatActivity {

    TextView avgScore;
    DatabaseReference dbRef;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE); //will hide the title
        getSupportActionBar().hide(); // hide the title bar
        this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN); //enable full screen
        setContentView(R.layout.score);
        avgScore = findViewById(R.id.textView2);
        dbRef = FirebaseDatabase.getInstance().getReference().child("Users");

        scoreRealTime();
    }

    public void scoreRealTime() {
        dbRef.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot snapshot) {
                double total = 0;
                for (DataSnapshot ds : snapshot.getChildren()){
                    double values = Double.parseDouble(ds.child("rating").getValue().toString());
                    total = total + values;
                }
                double average = (double) total / snapshot.getChildrenCount();
                avgScore.setText(String.format("%.2f", average));
            }

            @Override
            public void onCancelled(@NonNull DatabaseError error) {
            }
        });
    }
}

AndroidManifest.xml-

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.feedback">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity
            android:name=".MainActivity"
            android:screenOrientation="landscape">
        </activity>
        <activity
            android:name=".Score"
            android:screenOrientation="landscape">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

我假设displayScore()有一个非常简单的问题，但似乎无法找出它。 提前谢谢你。