Android答题APP按钮颜色异常：正确选项点击后变红而非绿色

AI 小北

2026-7-3

问题描述

我正在为期末项目开发一款答题应用，除按钮功能外其余功能均运行正常。按照代码逻辑，点击正确答案的按钮应变为绿色，错误选项按钮应变为红色，但实际操作中，点击正确选项时按钮却变为红色。

package com.example.final_gameplaydb;

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

import android.animation.Animator;
import android.annotation.SuppressLint;
import android.content.Intent;
import android.content.res.ColorStateList;
import android.graphics.Color;
import android.os.Bundle;
import android.os.CountDownTimer;
import android.os.Handler;
import android.util.Log;
import android.view.View;
import android.view.animation.DecelerateInterpolator;
import android.widget.TextView;
import android.widget.Button;
import android.widget.Toast;


import com.example.final_gameplaydb.R.id;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.firestore.FirebaseFirestore;
import com.google.firebase.firestore.QueryDocumentSnapshot;
import com.google.firebase.firestore.QuerySnapshot;

import java.util.ArrayList;
import java.util.List;

public class GameplayActivity extends AppCompatActivity implements View.OnClickListener {

    TextView question, timerNum, questionCount;
    Button first, second, third, fourth;
    List<Question> questionList;
    int questionNum, scoreNum;
    CountDownTimer countDown;
    FirebaseFirestore firestore = FirebaseFirestore.getInstance();
    boolean quizEnded = false;


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

        question = findViewById(R.id.Question);
        questionCount = findViewById(R.id.QuestionNum);
        timerNum = findViewById(R.id.TimerNum);

        first = findViewById(R.id.FirstChoice);
        second = findViewById(R.id.SecondChoice);
        third = findViewById(R.id.ThirdChoice);
        fourth = findViewById(R.id.FourthChoice);

        first.setOnClickListener(this);
        second.setOnClickListener(this);
        third.setOnClickListener(this);
        fourth.setOnClickListener(this);

        getQuestionsList();

        scoreNum = 0;

        countDown = new CountDownTimer(60000, 1000) {
            @Override
            public void onTick(long millisUntilFinished) {
                timerNum.setText(String.valueOf(millisUntilFinished / 1000));
                if (millisUntilFinished <= 0) {
                    countDown.cancel();
                }
            }
            @Override
            public void onFinish() {
                if(!quizEnded) {
                    quizEnded = true;
                    Intent intent = new Intent(GameplayActivity.this, ScoreActivity.class);
                    startActivity(intent);
                    finish();
                }

            }
        }.start();
    }

    private void getQuestionsList() {
        questionList = new ArrayList<>();

        firestore.collection("Difficulties").document("Categories")
                .collection("Easy")
                .get().addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
                    @Override
                    public void onComplete(@NonNull Task<QuerySnapshot> task) {
                        if (task.isSuccessful()) {
                            QuerySnapshot questions = task.getResult();

                            for(QueryDocumentSnapshot doc : questions){
                                questionList.add(new Question(doc.getString("Question"),
                                        doc.getString("A"),
                                        doc.getString("B"),
                                        doc.getString("C"),
                                        doc.getString("D"),
                                        doc.getString("Answer")));

                            }
                            setQuestion();

                        } else {
                            Log.e("FirestoreError", "Error getting documents: ", task.getException());
                            Toast.makeText(GameplayActivity.this, task.getException().getMessage(), Toast.LENGTH_SHORT).show();
                        }
                    }
                });
        }

    private void setQuestion() {

        //timerNum.setText(String.valueOf(60));

        question.setText(questionList.get(0).getQuestion());
        first.setText(questionList.get(0).getOptionA());
        second.setText(questionList.get(0).getOptionB());
        third.setText(questionList.get(0).getOptionC());
        fourth.setText(questionList.get(0).getOptionD());

        questionCount.setText(String.valueOf(1));

        questionNum = 0;

    }

    @SuppressLint("NonConstantResourceId")
    @Override
    public void onClick(View v) {
        String selectChoice = "";

        if (v.getId() == id.FirstChoice) {
            selectChoice = "first";
        } else if (v.getId() == id.SecondChoice) {
            selectChoice = "second";
        } else if (v.getId() == id.ThirdChoice) {
            selectChoice = "third";
        } else if (v.getId() == id.FourthChoice) {
            selectChoice = "fourth";
        }
        checkAnswer(selectChoice, v);
    }

    private void checkAnswer(String selectChoice, View view) {
        Button selectedButton = (Button) view;

        if (selectChoice.equals(questionList.get(questionNum).getCorrectAns())) {
            // right answer
            selectedButton.setBackgroundTintList(ColorStateList.valueOf(Color.GREEN));
            scoreNum++;
        } else {
            // wrong answer
            selectedButton.setBackgroundTintList(ColorStateList.valueOf(Color.RED));

            // Set the background tint of the correct answer to green
            switch (questionList.get(questionNum).getCorrectAns()) {
                case "first":
                    first.setBackgroundTintList(ColorStateList.valueOf(Color.GREEN));
                    break;
                case "second":
                    second.setBackgroundTintList(ColorStateList.valueOf(Color.GREEN));
                    break;
                case "third":
                    third.setBackgroundTintList(ColorStateList.valueOf(Color.GREEN));
                    break;
                case "fourth":
                    fourth.setBackgroundTintList(ColorStateList.valueOf(Color.GREEN));
                    break;
            }
        }

        // Delay for 1000 milliseconds before changing the question
        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                selectedButton.setEnabled(true);

                // Reset background tint of all buttons before changing the question
                selectedButton.setBackgroundTintList(null);
                first.setBackgroundTintList(null);
                second.setBackgroundTintList(null);
                third.setBackgroundTintList(null);
                fourth.setBackgroundTintList(null);

                changeQuestion();
            }
        }, 0500);
    }

    private void changeQuestion() {
            if (questionNum < questionList.size() - 1) {
                questionNum++;

                playAnim(question, 0, 0);
                playAnim(first, 0, 1);
                playAnim(second, 0, 2);
                playAnim(third, 0, 3);
                playAnim(fourth, 0, 4);

                questionCount.setText(String.valueOf(questionNum + 1));

                //timerNum.setText(String.valueOf(60));
            } else {
                // go to score activity
                Intent intent = new Intent(GameplayActivity.this, ScoreActivity.class);
                intent.putExtra("SCORE", String.valueOf(scoreNum));
                intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
                startActivity(intent);
                GameplayActivity.this.finish();
            }
    }

    private void playAnim(final View view, final int value, final int viewNum) {
        view.animate().alpha(value).scaleX(value).scaleY(value).setDuration(500)
                .setStartDelay(100).setInterpolator(new DecelerateInterpolator())
                .setListener(new Animator.AnimatorListener() {
                    @Override
                    public void onAnimationStart(Animator animation) {

                    }

                    @Override
                    public void onAnimationEnd(Animator animation) {
                        if (value == 0){
                            switch (viewNum){
                                case 0:
                                    ((TextView)view).setText(questionList.get(questionNum).getQuestion());
                                    break;
                                case 1:
                                    ((Button)view).setText(questionList.get(questionNum).getOptionA());
                                    break;
                                case 2:
                                    ((Button)view).setText(questionList.get(questionNum).getOptionB());
                                    break;
                                case 3:
                                    ((Button)view).setText(questionList.get(questionNum).getOptionC());
                                    break;
                                case 4:
                                    ((Button)view).setText(questionList.get(questionNum).getOptionD());
                                    break;
                            }
                            /**if (viewNum == 0){
                                ((Button)view).setBackgroundTintList(ColorStateList.valueOf(Color.parseColor("#03A9F4")));
                            }**/

                            playAnim(view,1,viewNum);
                        }
                    }

                    @Override
                    public void onAnimationCancel(Animator animation) {

                    }

                    @Override
                    public void onAnimationRepeat(Animator animation) {

                    }
                });
    }

}

问题分析与修复

核心问题在于Firestore存储的Answer字段值和代码中判断的字符串不匹配：
你将用户点击的按钮映射为"first"/"second"/"third"/"fourth"，但如果Firestore中Answer字段存的是"A"/"B"/"C"/"D"或者选项的具体文本，就会导致正确选项被判定为错误，从而触发红色背景逻辑。

具体修复方案

1. 匹配Firestore数据格式

根据你的Firestore实际存储情况修改映射逻辑：

如果Answer字段存的是"A"/"B"/"C"/"D"：

@SuppressLint("NonConstantResourceId")
@Override
public void onClick(View v) {
    String selectChoice = "";

    if (v.getId() == id.FirstChoice) {
        selectChoice = "A";
    } else if (v.getId() == id.SecondChoice) {
        selectChoice = "B";
    } else if (v.getId() == id.ThirdChoice) {
        selectChoice = "C";
    } else if (v.getId() == id.FourthChoice) {
        selectChoice = "D";
    }
    checkAnswer(selectChoice, v);
}

如果Answer字段存的是选项的完整文本：

@SuppressLint("NonConstantResourceId")
@Override
public void onClick(View v) {
    Button selectedBtn = (Button) v;
    String selectChoice = selectedBtn.getText().toString();
    checkAnswer(selectChoice, v);
}

2. 修复延迟时间语法错误

代码中0500是八进制数（对应十进制320），如果要设置500毫秒延迟，直接写500：

new Handler().postDelayed(new Runnable() {
    @Override
    public void run() {
        // 原有逻辑
    }
}, 500);

3. 添加调试日志（可选）

在checkAnswer方法开头添加日志，方便验证判断逻辑的输入值：

private void checkAnswer(String selectChoice, View view) {
    Log.d("AnswerCheck", "用户选择: " + selectChoice + " | 正确答案: " + questionList.get(questionNum).getCorrectAns());
    // 原有逻辑
}

内容的提问来源于stack exchange，提问作者yyweixh

Android答题APP按钮颜色异常：正确选项点击后变红而非绿色

具体修复方案 #

1. 匹配Firestore数据格式

2. 修复延迟时间语法错误

3. 添加调试日志（可选）

具体修复方案