In application theme style, flag windowDrawsSystemBarBackgrounds (<item name="android:windowDrawsSystemBarBackgrounds">) indicates:

In a common Paging Library architecture scheme, move instances to the correct positions.

The easiest way of adding menu items (to specify the options menu for an activity) is inflating an XML file into the Menu via MenuInflater. With menu_main.xml we can do it in this way:

What public methods are there in android.widget.Toast.Callback? (Choose two.)

LiveData.postValue() and LiveData.setValue() methods have some differences. So if you have a following code executed in the main thread:
liveData.postValue("a"); liveData.setValue("b");
What will be the correct statement?