example usage of the AppCompatSpinner

Android - material spinner.md

<android.support.design.widget.TextInputLayout
           android:layout_width="match_parent"
           android:layout_height="wrap_content">

    <android.support.v7.widget.AppCompatSpinner
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        bind:items="@{viewModel.spiinnerItems}" />

 </android.support.design.widget.TextInputLayout>

bind:items="@{viewModel.spiinnerItems}
what is this thing?
And why do you need TextInputLayout?
Please explain

@lectricas

bind:items="@{viewModel.spiinnerItems}

items is the BindingAdapter name set on a public static method in a ViewModel class. spiinerItems is the 2nd parameter passed to that method.