ListView 的自定义 ArrayAdapter (Android)

Question

I'm trying to show a Listview with Custom ArrayAdapter and i don't know what is my error. The console show this error:

java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.registro/com.example.registro.MainActivity}: java.lang.RuntimeException: Your content must have a ListView whose id attribute is 'android.R.id.list'.

Can someone help me. Thank you

MainActivity.java

public class MainActivity extends ListActivity {
private ListView List_View;

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

    List_View = (ListView) findViewById(R.id.list);
}

public void VerTabla (View view) {

    AdminBD admin = new AdminBD(this, "BaseDatos", null, 1);
    SQLiteDatabase BaseDatos = admin.getWritableDatabase();
    ArrayList<DataUsuario> contenidoTabla = new ArrayList<DataUsuario>();

    try {
        Cursor fila = BaseDatos.rawQuery("select dni, nombre, telefono from usuario", null);

        for(fila.moveToFirst(); !fila.isAfterLast(); fila.moveToNext()) {
            DataUsuario user = new DataUsuario(
                    fila.getString(0),
                    fila.getString(1),
                    fila.getInt(2)
            );
            contenidoTabla.add(user);
        }

        UsuarioAdapter myAdp = new UsuarioAdapter(this, R.layout.persona_fila_layout, contenidoTabla);

        List_View.setAdapter(myAdp);


    }catch(Exception e){
        e.printStackTrace();
    } finally {
        BaseDatos.close();
    }
}
}

DataUsuario.java

package com.example.registro;

public class DataUsuario {

private String dni;
private String nombre;
private Integer telefono;

public DataUsuario() {
    super();
}

public DataUsuario(String dni, String nombre, Integer telefono ) {
    super();
    this.dni = dni;
    this.nombre = nombre;
    this.telefono = telefono;
}

public String getDni() {
    return dni;
}

public void setDni(String dni) {
    this.dni = dni;
}

public String getNombre() {
    return nombre;
}

public void setNombre(String dni) {
    this.nombre = nombre;
}

public Integer getTelefono() {
    return telefono;
}

public void setTelefono(Integer telefono) {
    this.telefono = telefono;
}

@Override
public String toString() {
    return this.dni + " - " + this.nombre + " - " + this.telefono;
}
}

UsuarioAdapter.java

public class UsuarioAdapter extends ArrayAdapter<DataUsuario> {

private ArrayList<DataUsuario> usuarios;
private int resourceLayout;
private Context mContext;

public UsuarioAdapter(Context context, int textViewResourceId, ArrayList<DataUsuario> usuarios) {
    super(context, textViewResourceId, usuarios);
    this.resourceLayout = textViewResourceId;
    this.mContext = context;
    this.usuarios = usuarios;
}

public View getView(int position, View convertView, ViewGroup parent){

    View v = convertView;

    if (v == null) {
        LayoutInflater vi;
        vi = LayoutInflater.from(mContext);
        v = vi.inflate(resourceLayout, null);

    }

    DataUsuario i = usuarios.get(position);

    if (i != null) {
        TextView dnitag = (TextView) v.findViewById(R.id.dnitag);
        TextView dnidata = (TextView) v.findViewById(R.id.dnidata);
        TextView nombretag = (TextView) v.findViewById(R.id.nombretag);
        TextView nombredata = (TextView) v.findViewById(R.id.nombredata);
        TextView telefonotag = (TextView) v.findViewById(R.id.telefonotag);
        TextView telefonodata = (TextView) v.findViewById(R.id.telefonodata);

        // Chequeamos que los textview existan y los rellenamos
        if (dnitag != null){
            dnitag.setText("Dni: ");
        }
        if (dnidata != null){
            dnidata.setText(i.getDni());
        }
        if (nombretag != null){
            nombretag.setText("Nombre: ");
        }
        if (nombredata != null){
            nombredata.setText(i.getNombre());
        }
        if (telefonotag != null){
            telefonotag.setText("Teléfono: ");
        }
        if (telefonodata != null){
            telefonodata.setText(i.getTelefono());
        }
    }
    return v;
}
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<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"
tools:context=".MainActivity"
android:orientation="vertical">

<Button
    android:id="@+id/button3"
    android:layout_width="121dp"
    android:layout_height="wrap_content"
    android:onClick="VerTabla"
    android:text="Ver tabla" />

<ListView
    android:id="@+id/list"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    />
</LinearLayout>

persona_fila_layout.xml

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical">

<!-- Dni Tag -->
<TextView
    android:id="@+id/dnitag"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    />

<!-- Dni Data -->
<TextView
    android:id="@+id/dnidata"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    />

<!-- Nombre Tag -->
<TextView
    android:id="@+id/nombretag"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    />

<!-- Nombre Data -->
<TextView
    android:id="@+id/nombredata"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    />

<!-- Telefono Tag -->
<TextView
    android:id="@+id/telefonotag"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    />

<!-- Telefono data -->
<TextView
    android:id="@+id/telefonodata"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    />
</LinearLayout>

Answer 1

Your error log is telling you the solution to this:

Your content must have a ListView whose id attribute is 'android.R.id.list'.

Change id of your listview to @android:id/list like this:

<ListView
    android:id="@android:id/list"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    />
</LinearLayout>

You need to do this because you are extending ListActivity . It is not required to do this in any other activity.

Also please note that since ListActivity is subclass of android.app.Activity instead of AppCompatActivity, you won't be able to use backward compatibility features provided.

If you want to use AppCompat, it is better to add ListView to the your AppCompatActivity instead of extending ListActivity .

Edit :
Also replace the findViewByid() in your onCreate() since ListActivity already has the function that returns the ListView:

List_View = getListView();

Answer 2

You can't use android:id="@+id/list" .
In your layout use:

<ListView 
    android:id="@android:id/list"
    .....
    />

Check the official doc :

To do this, your own view MUST contain a ListView object with the id "@android:id/list" (or R.id.list if it's in code)