Can't use android:background with button from the new material components

The documentation for the MaterialButton class says:

Do not use the android:background attribute. MaterialButton manages its own background drawable, and setting a new background means MaterialButton can no longer guarantee that the new attributes it introduces will function properly. If the default background is changed, MaterialButton cannot guarantee well-defined behavior.

However, the GitHub readme says:

Note: MaterialButton is visually different from Button and AppCompatButton. One of the main differences is that AppCompatButton has a 4dp inset on the left and right sides, whereas MaterialButton does not.

This mentions only left/right inset, but the Attributes section of the readme shows that all four insets are supported:

So you could add these attributes to your <MaterialButton> tag:

android:insetTop="0dp"
android:insetBottom="0dp"

In the Material Components Library, the MaterialButton has a default style with insetBottom and insetTop with a value of 6dp.

You can change it using:

  <com.google.android.material.button.MaterialButton
      android:insetTop="0dp"
      android:insetBottom="0dp"
      ../>

If you want to change the background color you can use the app:backgroundTint attribute or you can override some theme attributes from a default style then you can use new materialThemeOverlay attribute.

In your case you can do something like:

<style name="MtButtonStyle"
 parent="Widget.MaterialComponents.Button">
   <item name=“materialThemeOverlay”>@style/GreenButtonThemeOverlay</item>
</style>

<style name="GreenButtonThemeOverlay">
  <item name="colorPrimary">@color/green</item>
</style>

Finally starting with the version 1.2.0-alpha06 you can use the android:background attribute in the MaterialButton.

<MaterialButton
    app:backgroundTint="@null"
    android:background="@drawable/button_drawable"
    ... />

Looking at https://medium.com/@velmm/material-button-in-android-e4391a243b17 I found that app:backgroundTint (and app:backgroundTintMode) works. It changes a color, but not a drawable selector.

Also you can replace <Button with <android.widget.Button.