I want to use databinding at the entrance to the navigation.
When I use fragment android:name="NavHostFragment" in the activity, the program can run normally;
but when I use fragment in the activity android:name="NavHostFragment" + databinding, the program will not run.
I hope to use databinding at the entrance of the navigation, please tell me how to use it?
The thrown exception:
java.lang.RuntimeException: Unable to start activity
ComponentInfo{com.example.appnavigationtodo/com.example.appnavigationtodo.MainActivity}:
android.view.InflateException: Binary XML file line #21: Binary XML
file line #21: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3092)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3235)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1926)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:6990)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1445)
Caused by: android.view.InflateException: Binary XML file line #21: Binary XML file line #21: Error inflating class fragment
Caused by: android.view.InflateException: Binary XML file line #21: Error inflating class fragment
Caused by: java.lang.IllegalArgumentException: Binary XML file line #21: Duplicate id 0x7f080050, tag null, or parent id 0xffffffff
with another fragment for androidx.navigation.fragment.NavHostFragment
at androidx.fragment.app.FragmentManagerImpl.onCreateView(FragmentManager.java:3752)
at androidx.fragment.app.FragmentController.onCreateView(FragmentController.java:120)
at androidx.fragment.app.FragmentActivity.dispatchFragmentsOnCreateView(FragmentActivity.java:405)
at androidx.fragment.app.FragmentActivity.onCreateView(FragmentActivity.java:387)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:780)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:863)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
at androidx.appcompat.app.AppCompatDelegateImpl.setContentView(AppCompatDelegateImpl.java:469)
at androidx.appcompat.app.AppCompatActivity.setContentView(AppCompatActivity.java:140)
at androidx.databinding.DataBindingUtil.setContentView(DataBindingUtil.java:303)
at androidx.databinding.DataBindingUtil.setContentView(DataBindingUtil.java:284)
at com.example.appnavigationtodo.MainActivity.onCreate(MainActivity.java:25)
at android.app.Activity.performCreate(Activity.java:7326)
at android.app.Activity.performCreate(Activity.java:7317)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1271)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3072)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3235)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1926)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:6990)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1445)
MainActivity.java：
public class MainActivity extends AppCompatActivity {
private ActivityMainBinding activityMainBinding;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
activityMainBinding = DataBindingUtil.setContentView(this, R.layout.activity_main);
}
}
activity_main.xml：
<layout 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">
<data>
</data>
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.appcompat.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/ToolbarTheme" />
<fragment
android:id="@+id/fragmentMain"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
app:defaultNavHost="true"
app:navGraph="@navigation/nav_main" />
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="@+id/bottomNavigationView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:menu="@menu/menu_bottom_navigation_view" />
</LinearLayout>
</layout>
You're calling setContentView twice, once with setContentView and a second time with DataBindingUtil.setContentView(). Instead, just use DataBindingUtil.setContentView(), which calls setContentView() itself internally:
public class MainActivity extends AppCompatActivity {
private ActivityMainBinding activityMainBinding;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
activityMainBinding = DataBindingUtil.setContentView(this,R.layout.activity_main);
}
}