Material Button Toggle Group single selection

Question

How can I force a MaterialButtonToggleGroup to act like a RadioGroup as in having at least one selected item always? Setting setSingleSelection(true)

Answer 1

Now you can achieve it using the app:selectionRequired attribute.
Something like:

Also you can programmatically use the method setSelectionRequired:

buttonGroup.setSelectionRequired(true);

Please note that this attribute requires a minimum of version 1.2.0-alpha03