Android 视图绑定根属性被忽略

Question

I'm trying to use View Binding in android, but the root's property ( layout_gravity, layout_width ) got ignored after build and installed,

it looks fine on design view ( wrap_content and center_vertical ).

i've enabled viewBinding in app gradle (android studio 3.6.1), and my root view group is a LinearLayout with some property

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center_vertical"
    android:orientation="vertical"
    tools:context=".MainActivity">
...

class MainActivity : AppCompatActivity() {
    private lateinit var binding: ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)
    }
}

and if i change layout_gravity to center or other value, it'll get unresolved reference: ActivityMainBinding in MainActivity

am i not supposed to use property on root layout?

Answer 1

so i switched to dataBinding instead of viewBinding

class MainActivity : AppCompatActivity() {
    private lateinit var binding: ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = DataBindingUtil.setContentView(this, R.layout.activity_main)
    }
}

<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">

    <LinearLayout
    ...