使用单选按钮在 Android 中制作测验应用程序

Question

I'm making a Quizz App for Android with 10 Questions, all of them with 4 Radio Buttons, and one button at the end to show the score. The problem is when I choose the correct answer it gives 5 points, but if I check another radio button the points will stay 5 and if I press again it sums 5. What is the best way to code this?

Here is the code:

package com.example.android.quizproject;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.RadioButton;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

int points = 0;

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

public void firstRadioButtons (View view){
    boolean checked = ((RadioButton) view).isChecked();
    switch (view.getId()) {
        case R.id.questionOneA:
            if (checked)
                points += 0;
                break;
        case R.id.questionOneB:
            if (checked)
                points += 0;
                break;
        case R.id.questionOneC:
            if (checked)
                points += 5;
                break;
        case R.id.questionOneD:
            if (checked)
                points += 0;
                break;
    }

}

public void showScore (View view) {
    TextView scoreTextView = (TextView) findViewById(R.id.score);
    scoreTextView.setText(" " + points);
}

}

Answer 1

You can make use of a counter vvariable which checks if the question has been previousy answered or not. Modify part of your code to this

public void firstRadioButtons (View view){
    boolean checked = ((RadioButton) view).isChecked();
    int count=0;
    switch (view.getId()) {
        case R.id.questionOneA:
            if (checked)
                {
            if(count!=0){
                points-=5;
                count=0;
                }
                }
                break;
        case R.id.questionOneB:
            if (checked)
                {
            if(count!=0){
                points-=5;
                count=0;
                }
                }
                break;
        case R.id.questionOneC:
            if (checked){
                points += 5;
                count+=1;}
                break;
        case R.id.questionOneD:
            if (checked)
                {
            if(count!=0){
                points-=5;
                count=0;
                }
                }
                break;
    }

}

Answer 2

Actually, the way you described it, it's common sense. If you click the right answer once, it will set it to 5, but if you press any other it will add 0 to it.

In general, it will print out 5 since you got the answer correct once, and the other questions are set to 0. There's really nothing to fix here, it's kind of common sense that your variable wouldn't read other than 5. Just like Abhriya said, you could add a counter increment value as done in ( her / his ) example.