Linear Layout com espaçamento em tela inteira

<?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"

android:padding="20dp"

tools:context=".JokeActivity">

<View

android:layout_width="1px"

android:layout_height="0px"

android:layout_weight="1"

/>

<TextView

android:id="@+id/text_joke"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:text="O texto aqui"

android:gravity="center"/>

<View

android:layout_width="1px"

android:layout_height="0px"

android:layout_weight="1"

/>

<Button

android:id="@+id/button_compartilhar"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:text="COMPARTILHAR" />

</LinearLayout>