Android Api 23更改导航视图headerLayout textview

我正在testing导航抽屉示例项目在Android中，我有一个问题在导航视图configuration文件标题中设置文本。

这是我的代码：

MainActivity.java

@Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); setSupportActionBar(toolbar); FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab); fab.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG) .setAction("Action", null).show(); } }); 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.setDrawerListener(toggle); toggle.syncState(); NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view); navigationView.setNavigationItemSelectedListener(this); TextView text = (TextView) findViewById(R.id.textView); texto.setText("HELLO"); } 

activity_main.xml中

 <?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"> <include layout="@layout/app_bar_main" android:layout_width="match_parent" android:layout_height="match_parent" /> <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/nav_header_main" app:menu="@menu/activity_main_drawer" /> </android.support.v4.widget.DrawerLayout> 

nav_header_main.xml

 <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="@dimen/nav_header_height" android:background="@drawable/side_nav_bar" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" android:theme="@style/ThemeOverlay.AppCompat.Dark" android:orientation="vertical" android:gravity="bottom"> <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:paddingTop="@dimen/nav_header_vertical_spacing" android:src="@android:drawable/sym_def_app_icon" android:id="@+id/imageView" /> <TextView android:layout_width="match_parent" android:layout_height="wrap_content" android:paddingTop="@dimen/nav_header_vertical_spacing" android:text="Android Studio" android:textAppearance="@style/TextAppearance.AppCompat.Body1" /> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="[e-mail]" android:id="@+id/textView" /> </LinearLayout> 

当我尝试设置文本视图的文本，我总是得到这个错误，它只发生在API级别23：

 java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference 

如何从主要活动更改nav_header_main.xml的Textview文本？

提前致谢

Answer 1

我有同样的问题，并能够避免与此代码：

  View header = LayoutInflater.from(this).inflate(R.layout.nav_header_main, null); navigationView.addHeaderView(header); TextView text = (TextView) header.findViewById(R.id.textView); text.setText("HELLO"); 

Answer 2

现在使用devise支持库的23.1.1版本，可以使用

 View header = navigationView.getHeaderView(0) TextView text = (TextView) header.findViewById(R.id.textView); 

Answer 3

Orium答案的作品，这也将工作。

 View header = navigationView.inflateHeaderView(R.layout.nav_header_main); TextView text = (TextView) header.findViewById(R.id.textView); texto.setText("HELLO"); 

Answer 4

这为我解决了这个问题

  View headerView = navigationView.inflateHeaderView(R.layout.header_view); txt_fullname = (TextView) headerView.findViewById(R.id.txt_fullname); txt_email = (TextView) headerView.findViewById(R.id.txt_email); 

Answer 5

或者如果你使用这个属性：

 <android.support.desibn.widget.NavigationView> ... app:headerLayout="@layout/your_header_layout"/> 

您可以：

 View header = mNavigationView.getHeaderView(0); TextView title = (TextView) header.findViewById(R.id.your_title_id); //Or something else 

Answer 6

 View headerView=navigationView.getChildAt(0); TextView tvName=(TextView)hView.findViewById(R.id.name); TextView tvEmail=(TextView)hView.findViewById(R.id.email); tvName.setText(data); tvEmail.setText(data);