Android - Saving Key-Value Sets

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <EditText
        android:id="@+id/edit_token"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="@string/edit_token"
        android:ems="10" >
        <requestFocus />
    </EditText>

    <Button
        android:id="@+id/button1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:onClick="ulozToken"
        android:text="@string/button_save_token" />

</LinearLayout>