<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:fitsSystemWindows="true"
  android:orientation="vertical">
 
  <FrameLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">
 
    <FrameLayout
      android:id="@+id/chat_container"
      android:layout_width="match_parent"
      android:layout_height="match_parent" />
 
    <ProgressBar
      android:id="@+id/waiting"
      style="@style/Widget.AppCompat.ProgressBar"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_gravity="center"
      android:visibility="visible" />
  </FrameLayout>
 
</LinearLayout>