Set android:windowSoftInputMode="adjustPan"
in your manifest file, and it will work as you expect.
E.g.
<application
android:name=".MainApplication"
android:allowBackup="true"
...
<activity
android:name=".MainActivity"
android:label="@string/app_name"
...
android:windowSoftInputMode="adjustPan">
...
</activity>
...
</application>