Как в TextView добавить ссылку на имя Activity?

Question

[run182]

В приложении есть Activity с layout, в нем TextView с параметром android:text="Профиль".
Как сделать, чтобы при вызове этого же layout из другого Activity, вместо "Профиль" добавлялось название того Activity?

Answer 1

[Дмитрий Серков]

TextView textView = (TextView)findViewById(R.id.textView);
textView.setText(R.string.activityname);

Comments

[run182]

При запуске приложение вылетает с ошибкой. Вот что в логах выходит: Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(int)' on a null object reference at com.example.run18.withtoolbar.PlacesActivity.onCreate(PlacesActivity.java:74)

Make Project в Android Studio ошибок не выдает.

Не могу понять в чем причина

[Дмитрий Серков]

run182: Код activity и layout покажи

[run182]

PlacesActivity.java

public class PlacesActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
    static final String LOG = "LOG_ListPlacesActivity";
    private static String url_db;
    private SharedPreferences ApiSettings;
    public static final String APP_PREFERENCES = "SETTINGS";
    public static final String APP_PREFERENCES_API_TOKEN = "API_TOKEN";
    private String ApiToken;
    private static final String TAG_PLACE_ID = "id";
    private static final String TAG_NAME = "name";
    private static final String TAG_ADDRESS = "address";

    private List<FeedPlace> feedsPlaces;
    private RecyclerView mRecyclerView;
    private ProgressBar progressBar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        ApiSettings = getSharedPreferences(APP_PREFERENCES, Context.MODE_PRIVATE);
        if (ApiSettings.contains(APP_PREFERENCES_API_TOKEN)) {
            ApiToken = ApiSettings.getString(APP_PREFERENCES_API_TOKEN, "");
            if(ApiToken.length() > 0) {

            } else {
                startActivity(new Intent(this, LoginActivity.class));
            }
        } else {
            startActivity(new Intent(this, LoginActivity.class));
        }
        setContentView(R.layout.places);

        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.addDrawerListener(toggle);
        toggle.syncState();
        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);

        TextView title = (TextView) findViewById(R.id.header_nav_name);
        title.setText(R.string.title_activity_list_places);
    }
}

places.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout 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:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start">

    <android.support.design.widget.CoordinatorLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <android.support.design.widget.AppBarLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:theme="@style/AppTheme.AppBarOverlay">

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                android:background="?attr/colorPrimary"
                app:popupTheme="@style/AppTheme.PopupOverlay" />

        </android.support.design.widget.AppBarLayout>

        <android.support.constraint.ConstraintLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_behavior="@string/appbar_scrolling_view_behavior">

            <android.support.v7.widget.RecyclerView
                android:id="@+id/recycler_view"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_marginTop="4dp"/>
            <RelativeLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent">
                <ProgressBar
                    android:id="@+id/progress_bar"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_centerInParent="true"/>
            </RelativeLayout>

        </android.support.constraint.ConstraintLayout>


    </android.support.design.widget.CoordinatorLayout>

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        app:headerLayout="@layout/header_nav"
        app:menu="@menu/menu" />

</android.support.v4.widget.DrawerLayout>

header_nav.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"
    android:layout_width="match_parent"
    android:layout_height="@dimen/nav_header_height"
    android:background="@color/colorPrimaryDark"
    android:gravity="bottom"
    android:orientation="horizontal"
    android:paddingBottom="10dp"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:theme="@style/ThemeOverlay.AppCompat.Dark">

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingTop="@dimen/nav_header_vertical_spacing"
        app:srcCompat="@drawable/logo_w" />

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/header_nav_name"
        android:paddingBottom="7dp"
        android:paddingLeft="16dp"
        android:text=""
        android:textSize="17dp"
        android:textStyle="bold"/>

</LinearLayout>

[Дмитрий Серков]

run182: TextView ("@+id/header_nav_name") еще не существует, поэтому и NullPointerException.

[run182]

Можно его как-то подцепить из лейаута виджета NavigationView, там то он прописан?

[Дмитрий Серков]

run182: Но само view NavigationView, еще не создано.