1st Solution
You can use app:backgroundTint to change back ground color of MaterialButton
<com.google.android.material.button.MaterialButton
android:id="@+id/bittrexJsonViewButton"
android:layout_width="0dp"
android:layout_height="@dimen/min_height"
android:layout_marginStart="@dimen/half_default_margin"
android:layout_marginEnd="@dimen/half_default_margin"
app:backgroundTint="@android:color/holo_orange_dark"
android:text="@string/json_view"
app:layout_constraintBottom_toBottomOf="@+id/binanceJsonViewButton"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@+id/binanceJsonViewButton"
app:layout_constraintTop_toTopOf="@+id/binanceJsonViewButton" />
2nd Solution
MaterialButton uses colorPrimary as background when button is in active state and colorOnSurface when disabled. So, you can define it in your theme and apply it on material buttons