How to add a button to a PreferenceScreen?

I'm quite new to Android Development and just came across Preferences. I found PreferenceScreen and wanted to create a login functionality with it. The only problem I have is that I don't know how I could add a "Login" button to the PreferenceScreen.

Here's what my PreferenceScreen looks like:

<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
...
    <PreferenceScreen android:title="@string/login" android:key="Login">
        <EditTextPreference android:persistent="true" android:title="@string/username" android:key="Username"></EditTextPreference>
        <EditTextPreference android:title="@string/password" android:persistent="true" android:password="true" android:key="Password"></EditTextPreference>
    </PreferenceScreen>
...
</PreferenceScreen>

The Button should be right under the two EditTextPreferences.

Is there a simple solution for this problem? The one solution I found was not working because I use sub PreferenceScreens.

Update:

I figured out that i can add buttons this way:

<PreferenceScreen android:title="@string/login" android:key="Login">
        <EditTextPreference android:persistent="true" android:title="@string/username" android:key="Username"></EditTextPreference>
        <EditTextPreference android:title="@string/password" android:persistent="true" android:password="true" android:key="Password"></EditTextPreference>
        <Preference android:layout="@layout/loginButtons" android:key="loginButtons"></Preference>
</PreferenceScreen>

and the layout file