Android 9 Development Cookbook - Third Edition

How to do it...

1. Edit the res/layout/activity_main.xml file so it includes a button as defined here:

<Button    android:id="@+id/buttonLeft"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_alignParentLeft="true"    android:layout_centerVertical="true"    android:onClick="onClickLeft"    android:text="Left Button"    app:layout_constraintBottom_toBottomOf="parent"    app:layout_constraintHorizontal_bias="0.0"    app:layout_constraintLeft_toLeftOf="parent"    app:layout_constraintRight_toRightOf="parent"    app:layout_constraintTop_toTopOf="parent"/>

2. Now make a copy of activity_main.xml and call it activity_main2.xml. Change the button so it matches the following:

<Button    android:id="@+id/buttonLeft"    android:layout_width="wrap_content" ...