How to set Android DataBinding in nested layouts

Question

I just read about the data binding function in android. I tried to snap a view from a nested layout. My activity is the default android template DrawerMenuActivity , and it has a content_my_activity layout nested in an activity_my_activity layout.

I have 3 automatically generated binding classes. MyActivityBinding , AppBarMyActivityBinding and ContentMyActivityBinding .

I tried to initialize all 3 classes, as shown below:

MyActivity.java

 MyActivityBinding activityBinding; AppBarMyActivityBinding appBarBinding; ContentMyActivityBinding contentBinding; protected void onCreate(Bundle savedInstanceState){ super.onCreate(savedInstanceState); activityBinding = DataBindingUtils.setContentView(this, R.layout.activity_my_activity); appBarBinding = DataBindingUtils.setContentView(this, R.layout.app_bar_my_activity); contentBinding = DataBindingUtils.setContentView(this, R.layout.content_my_activity); setName(); } private void setName(){ contentBinding.setFirstName("Omkar"); } 

But this throws a RuntimeException, as shown below:

 E/AndroidRuntime: FATAL EXCEPTION: main Process: com.example, PID: 18305 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example/com.example.userInterface.activity.MyActivity}: android.view.InflateException: Binary XML file line #35: Binary XML file line #27: Error inflating class fragment at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2426) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490) at android.app.ActivityThread.access$900(ActivityThread.java:154) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:148) at android.app.ActivityThread.main(ActivityThread.java:5443) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) Caused by: android.view.InflateException: Binary XML file line #35: Binary XML file line #27: Error inflating class fragment at android.view.LayoutInflater.inflate(LayoutInflater.java:539) at android.view.LayoutInflater.inflate(LayoutInflater.java:423) at android.view.LayoutInflater.inflate(LayoutInflater.java:374) at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:280) at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140) at android.databinding.DataBindingUtil.setContentView(DataBindingUtil.java:276) at com.example.userInterface.activity.MyActivity.onCreate(MyActivity.java:88) at android.app.Activity.performCreate(Activity.java:6259) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1130) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2379) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490) at android.app.ActivityThread.access$900(ActivityThread.java:154) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:148) at android.app.ActivityThread.main(ActivityThread.java:5443) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) Caused by: android.view.InflateException: Binary XML file line #27: Error inflating class fragment at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:782) at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704) at android.view.LayoutInflater.rInflate(LayoutInflater.java:835) at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) at android.view.LayoutInflater.rInflate(LayoutInflater.java:838) at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) at android.view.LayoutInflater.parseInclude(LayoutInflater.java:971) at android.view.LayoutInflater.rInflate(LayoutInflater.java:831) at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) 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 android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:280) at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140) at android.databinding.DataBindingUtil.setContentView(DataBindingUtil.java:276) at com.example.userInterface.activity.MyActivity.onCreate(MyActivity.java:88) at android.app.Activity.performCreate(Activity.java:6259) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1130) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2379) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490) at android.app.ActivityThread.access$900(ActivityThread.java:154) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:148) at android.app.ActivityThread.main(ActivityThread.java:5443) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) Caused by: java.lang.IllegalArgumentException: Binary XML file line #27: Duplicate id 0x7f0e0081, tag null, or parent id 0xffffffff with another fragment for com.google.android.gms.maps.SupportMapFragment at android.support.v4.app.FragmentManagerImpl.onCreateView(FragmentManager.java:2416) at android.support.v4.app.FragmentController.onCreateView(FragmentController.java:120) at android.support.v4.app.FragmentActivity.dispatchFragmentsOnCreateView(FragmentActivity.java:374) at android.support.v4.app.BaseFragmentActivityHoneycomb.onCreateView(BaseFragmentActivityHoneycomb.java:33) at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:75) at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:754) at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704) at android.view.LayoutInflater.rInflate(LayoutInflater.java:835) at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) at android.view.LayoutInflater.rInflate(LayoutInflater.java:838) at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) at android.view.LayoutInflater.parseInclude(LayoutInflater.java:971) at android.view.LayoutInflater.rInflate(LayoutInflater.java:831) at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) 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 android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:280) at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140) at android.databinding.DataBindingUtil.setContentView(DataBindingUtil.java:276) at com.example.userInterface.activity.MyActivity.onCreate(MyActivity.java:88) at android.app.Activity.performCreate(Activity.java:6259) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1130) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2379) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490) at android.app.ActivityThread.access$900(ActivityThread.java:154) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:148) at android.app.ActivityThread.main(ActivityThread.java:5443) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) 

How to link the view from content_my_activity in the MyActivity.java class, any help would be appreciated.

Thanks.

Answer 1

DataBindingUtils.setContentView() does exactly what it is called: it sets the current view for this parameter. I don’t think you want your AppBar be all view, or you?

However, I assume that you include your layouts in your layout_activity_main.xml . George Gora wrote a blog post about this feature. Sample code from this post.

The first example might be your layout_activity_main.xml (or you called it nonetheless), where you include the AppBar , your Content and so on.

 hello_world.xml <layout xmlns:android="http://schemas.android.com/apk/res/android"> <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <TextView android:id="@+id/hello" android:layout_width="wrap_content" android:layout_height="wrap_content"/> <include android:id="@+id/world1" layout="@layout/included_layout"/> <include android:id="@+id/world2" layout="@layout/included_layout"/> </LinearLayout> </layout> included_layout.xml <?xml version="1.0" encoding="utf-8"?> <layout xmlns:android="http://schemas.android.com/apk/res/android"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:id="@+id/world"/> </layout> 

Now that the layouts used are clear, you need to go to the ActivityMain , initialize the DataBinding and access your fields:

 //This works if you have used a variable in your <data> tag and you have built your project afterwards, if you don't have an activity HelloWorldBinding binding = HelloWorldBinding.inflate(getLayoutInflater()); //if you have an activity, you can use setContentView from the DataBindingUtils. Don't forget to delete the generic setContentView HelloWorldBinding binding = DataBindingUtil.setContentView(this, R.layout.activity_my_activity); //Once you have accomplished the above, you can access your data-bound fields like this: binding.hello.setText("Hello"); binding.world1.world.setText("First World"); binding.world2.world.setText("Second World"); 

It is important to set the Ids in the <include> tags for proper access to them in your Activity .

Answer 2

you can pass objects to XML ... xmlns:bind namespace is required (similar to xmlns:app ).

 <?xml version="1.0" encoding="utf-8"?> <layout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:bind="http://schemas.android.com/apk/res-auto"> <data> <variable name="user" type="com.example.User"/> </data> <LinearLayout android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <include layout="@layout/name" bind:user="@{user}"/> <include layout="@layout/contact" bind:user="@{user}"/> </LinearLayout> </layout> 

Example source: layouts and binding expressions .