Complete source code in Android How to Reuse Views and Layouts With INCLUDE and MERGE
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="tech.codingpoint.includemergeexample.MainActivity">
<include
android:id="@+id/progressbar1"
layout="@layout/circular_progressbar" />
<include
android:id="@+id/progressbar2"
layout="@layout/circular_progressbar"
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_margin="16dp" />
<include layout="@layout/two_buttons" />
</LinearLayout>
circle.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:innerRadiusRatio="2.5"
android:shape="ring"
android:thickness="4dp"
android:useLevel="true">
<solid android:color="@color/colorAccent" />
</shape>
circular_progressbar.xml
<?xml version="1.0" encoding="utf-8"?>
<ProgressBar xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
style="?android:progressBarStyleHorizontal"
android:layout_width="150dp"
android:layout_height="150dp"
android:progressDrawable="@drawable/circle"
tools:progress="80" />
two_buttons.xml
<?xml version="1.0" encoding="utf-8"?>
<merge xmlns:android="http://schemas.android.com/apk/res/android">
<!-- Set the IDs here and use them in an activity as usual -->
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button 1" />
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button 2" />
</merge>