使用getStringArrayListExtra时崩溃

Question

我使用getStringArrayListExtra（）搜索将列表从一个活动传输到另一个活动。这在第一次（从MainActivity到Diag2Activity）时运行良好，但在第二次（从Diag2Activity到SSToActivity）时应用程序崩溃。

每次我使用相同的方法：第一次活动：

ArrayList<String> BDD = new ArrayList<String>();
BDD.add(tri);

Intent Diag2ActivityIntent = new Intent(MainActivity.this, Diag2Activity.class);
Diag2ActivityIntent.putStringArrayListExtra("BDD", BDD);
startActivity(Diag2ActivityIntent);

第二项活动：

Intent i = getIntent();
    ArrayList<String> BDD = i.getStringArrayListExtra("BDD");

谁能告诉我错误可能来自哪里？提前谢谢

请在下面找到完整的代码：

主要活动。JAVA

public class MainActivity extends AppCompatActivity {

Button mboutonContinuer;
TextView medit_text_gene_1;

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

    //appel des différents éléments de l'interface
    mboutonContinuer = findViewById(R.id.boutonContinuer);
    medit_text_gene_1 = findViewById(R.id.edit_text_gene_1);


    //Action quand on clique sur le bouton "continuer" :
    mboutonContinuer.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            //Récupération des valeurs inscrites dans les Edittext
            String tri = medit_text_gene_1.getText().toString();


            //écriture de la Base De Données
            ArrayList<String> BDD = new ArrayList<String>();
            BDD.add(tri);

            //En attendant de pouvoir ajouter un 2ème contact
            BDD.add("rien");

            //Redirection sur la prochaine page
            Intent Diag2ActivityIntent = new Intent(MainActivity.this, Diag2Activity.class);
            Diag2ActivityIntent.putStringArrayListExtra("BDD", BDD);
            startActivity(Diag2ActivityIntent);


        }
    });
}

}

主要活动。xml

<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".Controller.MainActivity"
>

<ScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <TextView
            android:layout_marginTop="30dp"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="left"
            android:text="Trigramme du diagnostiqueur"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            android:layout_marginLeft="30dp"/>

        <EditText
            android:id="@+id/edit_text_gene_1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:drawableLeft="@drawable/ic_tech"
            android:hint="XXX"
            android:inputType="textCapCharacters"
            android:maxLength="3"
            android:paddingHorizontal="30dp" />

        <Button
            android:id="@+id/boutonContinuer"
            android:layout_width="220dp"
            android:layout_height="68dp"
            android:layout_marginTop="40dp"
            android:layout_marginRight="40dp"
            android:layout_gravity="right"
            android:text="Continuer ->"
            />


    </LinearLayout>
</ScrollView>

诊断2Activity.java

public class Diag2Activity extends AppCompatActivity {

Button mboutonContinuer2;
TextView medit_text_sst_1;



@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_diag2);


    Intent i = getIntent();
    ArrayList<String> BDD = i.getStringArrayListExtra("BDD");

    mboutonContinuer2 = findViewById(R.id.boutonContinuer2);
    medit_text_sst_1 = findViewById(R.id.edit_text_nb_ech);



    mboutonContinuer2.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            //Récupération des valeurs inscrites dans les Edittext
            String brt = medit_text_sst_1.getText().toString();

            //écriture de la base de données
            BDD.add(brt);

            //Redirection vers la prochaine page
            Intent SstO1ActivityIntent = new Intent(Diag2Activity.this, SstO1Activity.class);
            SstO1ActivityIntent.putStringArrayListExtra("BDD", BDD);
            startActivity(SstO1ActivityIntent);

        }
    });
}

}

活动2。xml

<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".Controller.Diag2Activity">




<ScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical" >


        <EditText
            android:id="@+id/edit_text_nb_ech"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:drawableLeft="@drawable/ic_ech4"
            android:hint="X"
            android:inputType="number"
            android:maxLength="2"
            android:paddingHorizontal="30dp" />

        <Button
            android:id="@+id/boutonContinuer2"
            android:layout_width="220dp"
            android:layout_height="68dp"
            android:layout_gravity="right"
            android:layout_marginTop="40dp"
            android:layout_marginRight="40dp"
            android:text="Continuer ->" />
    </LinearLayout>
</ScrollView>

SstO1Activity.java

public class SstO1Activity extends AppCompatActivity {

Button mboutonContinuer3;
Button mboutonech;


Intent i = getIntent();
ArrayList<String> BDD = i.getStringArrayListExtra("BDD");


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_sst_o1);

    mboutonContinuer3 = findViewById(R.id.boutonContinuer3);

    mboutonContinuer3.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            BDD.add("cc");

            Intent WorkinprogressActivityIntent = new Intent(SstO1Activity.this, WorkinprogressActivity.class);
            startActivity(WorkinprogressActivityIntent);
        }
    });
}

活动1。xml

<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".Controller.SstO1Activity">



<ScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical" >


        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="40dp"
            android:gravity="left"
            android:text="Ajouter un commentaire si besoins"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="120dp"
            android:id="@+id/editText_test1"
            android:background="#DCDCDC"
            android:gravity="top|left"
            android:inputType="textMultiLine|text"
            android:padding="10dp"
            android:hint="Commentaire..."/>

        <Button
            android:id="@+id/boutonContinuer3"
            android:layout_width="220dp"
            android:layout_height="68dp"
            android:layout_gravity="right"
            android:layout_marginTop="20dp"
            android:layout_marginRight="40dp"
            android:text="Finir le diagnostic" />
    </LinearLayout>
</ScrollView>

Answer 1

将下面的代码放入OnCreate方法的SstO1Activity.java文件中。

Intent i = getIntent();
ArrayList<String> BDD = i.getStringArrayListExtra("BDD");