Android : Créer des styles

<style name="monTexteStyle">
    <item name="android:textColor">#9C27B0</item>
    <item name="android:textSize">20dp</item>
</style>

<style name="layoutStyle">
    <item name="android:background">#E91E63</item>
    <item name="android:padding">10dp</item>
</style>

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    style="@style/layoutStyle">
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:text="Button1"
        style="@style/monTexteStyle"/>
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:text="Button1"
        android:backgroundTint="#FFEB3B"/>
</LinearLayout>

3.ajouter un border,raduis...

Créer un style(monStyle.xml) dans le dossier drawable

monStyle.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
 <gradient
        android:startColor="#fff"
        android:centerColor="#000"
        android:endColor="#fff"
        android:angle="270" />
    <corners android:radius="5dp" />
    <stroke android:width="20px" android:color="#009688" />
</shape>

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:background="@drawable/monstyle">
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Hello"
        style="@style/monTexteStyle"/>
</LinearLayout>