使用Intent而不是'saveInstance'保存多个单选按钮状态

Question

简而言之，我正在制作一个简单的症状检查程序，使一般用户可以回答是/否问题。我是Android Studio的新手（仅编写了不到一周的时间），并尝试使移动应用程序保存单选按钮的状态，因此，如果用户回溯页面，则会显示选中的单选按钮。我将每个问题的是和否单选按钮分组到单独的单选组中，以便在每个问题下选择是或否。

不幸的是，即使进入下一个问题页面，按钮也保持未选中状态。无论如何，我编写的代码可以轻松地放入意图或共享首选项中吗？

问题活动XML代码，以显示单选按钮的分组方式：

         <RadioGroup
            android:id="@+id/radioGroup"
            android:layout_width="214dp"
            android:layout_height="59dp"
            android:layout_marginTop="124dp"
            app:layout_constraintStart_toStartOf="@+id/textView2"
            app:layout_constraintTop_toTopOf="parent">

            <RadioButton
                android:id="@+id/radioButton"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Yes"
                app:layout_constraintTop_toTopOf="parent"
                tools:layout_conversion_absoluteHeight="32dp"
                tools:layout_conversion_absoluteWidth="55dp"
                tools:layout_editor_absoluteX="18dp"
                tools:layout_editor_absoluteY="134dp" />

            <RadioButton
                android:id="@+id/radioButton20"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="No"
                app:layout_constraintTop_toTopOf="parent"
                tools:layout_conversion_absoluteHeight="32dp"
                tools:layout_conversion_absoluteWidth="50dp"
                tools:layout_editor_absoluteX="18dp"
                tools:layout_editor_absoluteY="300dp" />

        </RadioGroup>

这是链接到Questions活动的“ Questions” java文件：

public class Questions extends AppCompatActivity {

private RadioButton radioButton;
private RadioButton radioButton2;
private RadioButton radioButton3;
private RadioButton radioButton4;
private RadioButton radioButton5;
private RadioButton radioButton6;
private RadioButton radioButton7;
private RadioButton radioButton8;
private RadioButton radioButton9;
private RadioButton radioButton10;
private RadioButton radioButton11;
private RadioButton radioButton12;


@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
    super.onSaveInstanceState(savedInstanceState);

    //Question 1

    radioButton = findViewById(R.id.radioButton); //yes
    radioButton2 = findViewById(R.id.radioButton20); //no

    //Question 2

    radioButton3 = findViewById(R.id.radioButton4); //yes
    radioButton4 = findViewById(R.id.radioButton2); //no

    //Question 3

    radioButton5 = findViewById(R.id.radioButton6); //yes
    radioButton6 = findViewById(R.id.radioButton5); //no

    //Question 4

    radioButton7 = findViewById(R.id.radioButton7); //yes
    radioButton8 = findViewById(R.id.radioButton8); //no

    //Question 5

    radioButton9 = findViewById(R.id.radioButton9); //yes
    radioButton10 = findViewById(R.id.radioButton10); //no

    //Question 6

    radioButton11 = findViewById(R.id.radioButton12); //yes
    radioButton12 = findViewById(R.id.radioButton11); //no


    savedInstanceState.putBoolean("myOption1", radioButton.isChecked());
    savedInstanceState.putBoolean("myOption2", radioButton2.isChecked());
    savedInstanceState.putBoolean("myOption3", radioButton3.isChecked());
    savedInstanceState.putBoolean("myOption4", radioButton4.isChecked());
    savedInstanceState.putBoolean("myOption5", radioButton5.isChecked());
    savedInstanceState.putBoolean("myOption6", radioButton6.isChecked());
    savedInstanceState.putBoolean("myOption7", radioButton7.isChecked());
    savedInstanceState.putBoolean("myOption8", radioButton8.isChecked());
    savedInstanceState.putBoolean("myOption9", radioButton9.isChecked());
    savedInstanceState.putBoolean("myOption10", radioButton10.isChecked());
    savedInstanceState.putBoolean("myOption11", radioButton11.isChecked());
    savedInstanceState.putBoolean("myOption12", radioButton12.isChecked());
    }

@Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
    super.onRestoreInstanceState(savedInstanceState);

    radioButton.setChecked(savedInstanceState.getBoolean("myOption1"));
    radioButton2.setChecked(savedInstanceState.getBoolean("myOption2"));
    radioButton3.setChecked(savedInstanceState.getBoolean("myOption3"));
    radioButton4.setChecked(savedInstanceState.getBoolean("myOption4"));
    radioButton5.setChecked(savedInstanceState.getBoolean("myOption5"));
    radioButton6.setChecked(savedInstanceState.getBoolean("myOption6"));
    radioButton7.setChecked(savedInstanceState.getBoolean("myOption7"));
    radioButton8.setChecked(savedInstanceState.getBoolean("myOption8"));
    radioButton9.setChecked(savedInstanceState.getBoolean("myOption9"));
    radioButton10.setChecked(savedInstanceState.getBoolean("myOption10"));
    radioButton11.setChecked(savedInstanceState.getBoolean("myOption11"));
    radioButton12.setChecked(savedInstanceState.getBoolean("myOption12"));

    }
}

该解决方案的最终目标是利用所有选中的单选按钮框，做出一个大的'if then'语句，以进行患者症状诊断。

深入了解实现非常有用，谢谢。

这是@JakeB的整个课程：

package com.example.mhtapplication;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.RadioButton;

public class Questions extends AppCompatActivity {

private Button button2;

private RadioButton radioButton;
private RadioButton radioButton2;
private RadioButton radioButton3;
private RadioButton radioButton4;
private RadioButton radioButton5;
private RadioButton radioButton6;
private RadioButton radioButton7;
private RadioButton radioButton8;
private RadioButton radioButton9;
private RadioButton radioButton10;
private RadioButton radioButton11;
private RadioButton radioButton12;



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

    button2 = (Button) findViewById(R.id.button2);
    button2.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            openquestion2();
        }
    });

    //Question 1
    radioButton = findViewById(R.id.radioButton); //yes
    radioButton2 = findViewById(R.id.radioButton20); //no
    //Question 2
    radioButton3 = findViewById(R.id.radioButton4); //yes
    radioButton4 = findViewById(R.id.radioButton2); //no
    //Question 3
    radioButton5 = findViewById(R.id.radioButton6); //yes
    radioButton6 = findViewById(R.id.radioButton5); //no
    //Question 4
    radioButton7 = findViewById(R.id.radioButton7); //yes
    radioButton8 = findViewById(R.id.radioButton8); //no
    //Question 5
    radioButton9 = findViewById(R.id.radioButton9); //yes
    radioButton10 = findViewById(R.id.radioButton10); //no
    //Question 6
    radioButton11 = findViewById(R.id.radioButton12); //yes
    radioButton12 = findViewById(R.id.radioButton11); //no
    }

public void openquestion2() {
    Intent intent = new Intent(this, Question2.class);
    startActivity(intent);
   }

@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
    super.onSaveInstanceState(savedInstanceState);


    savedInstanceState.putBoolean("myOption1", radioButton.isChecked());
    savedInstanceState.putBoolean("myOption2", radioButton2.isChecked());
    savedInstanceState.putBoolean("myOption3", radioButton3.isChecked());
    savedInstanceState.putBoolean("myOption4", radioButton4.isChecked());
    savedInstanceState.putBoolean("myOption5", radioButton5.isChecked());
    savedInstanceState.putBoolean("myOption6", radioButton6.isChecked());
    savedInstanceState.putBoolean("myOption7", radioButton7.isChecked());
    savedInstanceState.putBoolean("myOption8", radioButton8.isChecked());
    savedInstanceState.putBoolean("myOption9", radioButton9.isChecked());
    savedInstanceState.putBoolean("myOption10", radioButton10.isChecked());
    savedInstanceState.putBoolean("myOption11", radioButton11.isChecked());
    savedInstanceState.putBoolean("myOption12", radioButton12.isChecked());
    }

@Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
    super.onRestoreInstanceState(savedInstanceState);

    radioButton.setChecked(savedInstanceState.getBoolean("myOption1"));
    radioButton2.setChecked(savedInstanceState.getBoolean("myOption2"));
    radioButton3.setChecked(savedInstanceState.getBoolean("myOption3"));
    radioButton4.setChecked(savedInstanceState.getBoolean("myOption4"));
    radioButton5.setChecked(savedInstanceState.getBoolean("myOption5"));
    radioButton6.setChecked(savedInstanceState.getBoolean("myOption6"));
    radioButton7.setChecked(savedInstanceState.getBoolean("myOption7"));
    radioButton8.setChecked(savedInstanceState.getBoolean("myOption8"));
    radioButton9.setChecked(savedInstanceState.getBoolean("myOption9"));
    radioButton10.setChecked(savedInstanceState.getBoolean("myOption10"));
    radioButton11.setChecked(savedInstanceState.getBoolean("myOption11"));
    radioButton12.setChecked(savedInstanceState.getBoolean("myOption12"));

   }
} 

Answer 1

当您导航回到上一个活动时，它可能会生成一个新的活动而不是重新使用旧的活动，请将清单中的活动启动模式设置为“ singleInstance”。

42P07