Question

如何从导航器抽屉标题中获取textView？我正在尝试这个：

 DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
 TextView text = (TextView) drawer.findViewById(R.id.textViewNames);
 text.setText("HELLO");

或

 NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
 try {
      View header = LayoutInflater.from(this).inflate(R.layout.nav_header_profiler, null);
      navigationView.addHeaderView(header);
      TextView text = (TextView) header.findViewById(R.id.textViewNames);
      text.setText("HELLO");
 } catch (Exception e) {
      Toast.makeText(getApplicationContext(),e.toString(), Toast.LENGTH_LONG).show();
 }

但没有任何效果。我总是得到`NullPointerException。出于某种原因，这种方法只是吸引控制工作：

 @SuppressWarnings("StatementWithEmptyBody")
 @Override
 public boolean onNavigationItemSelected(MenuItem item) {
      TextView textView = (TextView) findViewById(R.id.textViewNames);
      textView.setText(LoginActivity.FIRST_NAME + "\n" + LoginActivity.LAST_NAME);

      // Handle navigation view item clicks here.
      int id = item.getItemId();

      if (id == R.id.nav_camera) {
           // Handle the camera action
      } else if (id == R.id.nav_gallery) {

      } else if (id == R.id.nav_slideshow) {

      } else if (id == R.id.nav_manage) {

      } else if (id == R.id.Find) {

      } else if (id == R.id.LogOut) {

      }

      DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
      drawer.closeDrawer(GravityCompat.START);
      return true;
 }

编辑：我的日志：

02-07 08：00：04.307 8346-8346 / com.example.krystian.beacon E / AndroidRuntime：FATAL EXCEPTION：main 处理：com.example.krystian.beacon，PID：8346 java.lang.RuntimeException：无法启动活动ComponentInfo {com.example.krystian.beacon / com.example.krystian.beacon.Witaj_Activity}：java.lang.NullPointerException 在android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2184）在android.app.ActivityThread.handleLaunchActivity（ActivityThread.java:2233）在android.app.ActivityThread.access $ 800（ActivityThread.java:135）在android.app.ActivityThread $ H.handleMessage（ActivityThread.java:1196）在android.os.Handler.dispatchMessage（Handler.java:102）在android.os.Looper.loop（Looper.java:136）在android.app.ActivityThread.main（ActivityThread.java:5001） at java.lang.reflect.Method.invokeNative（Native Method）在java.lang.reflect.Method.invoke（Method.java:515）在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:785）在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:601） at dalvik.system.NativeStart.main（Native Method）引起：java.lang.NullPointerException 在com.example.krystian.beacon.Witaj_Activity.onCreate（Witaj_Activity.java:45）在android.app.Activity.performCreate（Activity.java:5231）在android.app.Instrumentation.callActivityOnCreate（Instrumentation.java:1087）在android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2148）在android.app.ActivityThread.handleLaunchActivity（ActivityThread.java:2233）在android.app.ActivityThread.access $ 800（ActivityThread.java:135）在android.app.ActivityThread $ H.handleMessage（ActivityThread.java:1196）在android.os.Handler.dispatchMessage（Handler.java:102）在android.os.Looper.loop（Looper.java:136）在android.app.ActivityThread.main（ActivityThread.java:5001） at java.lang.reflect.Method.invokeNative（Native Method）在java.lang.reflect.Method.invoke（Method.java:515）在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:785）在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:601）在dalvik.system.NativeStart.main（本地方法）

Answer 1

删除此属性应用：headerLayout =＆＃34; @ layout / nav_header_main＆＃34;

<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:menu="@menu/activity_main_activiy_drawer" />

并在MainActivity中添加动态添加

 NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);
        View headerView = navigationView.inflateHeaderView(R.layout.nav_header_main_activiy);
        ImageView user_iv = (ImageView) headerView.findViewById(R.id.user_iv);
        TextView fullName_tv = (TextView) headerView.findViewById(R.id.fullName_tv);
       TextView userEmail_tv = (TextView) headerView.findViewById(R.id.userEmail_tv);

        fullName_tv.setText("Your Full Name");
        userEmail_tv.setText("Your Email id");

这是我的工作

Android navigatorDrawer标头中的SetText TextView

1 个答案: