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<page  xmlns="http://projectmallard.org/1.0/"
       xmlns:its="http://www.w3.org/2005/11/its"
       type="topic" style="task"
       id="desktop-shield">

  <info>
    <link type="guide" xref="appearance" />

    <revision pkgversion="3.22" date="2017-01-09" status="draft" />

    <credit type="author copyright">
      <name>Matthias Clasen</name>
      <email its:translate="no">matthias.clasen@gmail.com</email>
      <years>2012</years>
    </credit>
    <credit type="author copyright">
      <name>Michael Hill</name>
      <email its:translate="no">mdhillca@gmail.com</email>
      <years>2012</years>
    </credit>
    <credit type="editor">
      <name>Jana Svarova</name>
      <email its:translate="no">jana.svarova@gmail.com</email>
      <years>2013</years>
    </credit>
    <credit type="editor">
      <name>Petr Kovar</name>
      <email its:translate="no">pknbe@volny.cz</email>
      <years>2017</years>
    </credit>

    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>

    <desc>Change the background of the lock screen shield.</desc>
  </info>

  <title>Change the lock screen shield</title>

  <p>The <em>lock screen shield</em> is the screen that quickly slides down when
  the system is locked. The background of the lock screen shield is controlled by
  the <sys>org.gnome.desktop.screensaver.picture-uri</sys> GSettings key. Since
  <sys>GDM</sys> uses its own <sys>dconf</sys> profile, you can set the default
  background by changing the settings in that profile.</p>

<steps>
  <title>Set the org.gnome.desktop.screensaver.picture-uri key</title>
  <include href="dconf-snippets.xml"
      xpointer="xpointer(/*/*[@xml:id='dconf-profile-gdm'])"
      xmlns="http://www.w3.org/2001/XInclude"/>
  <item><p>Create a <sys>gdm</sys> database for machine-wide settings in
  <file>/etc/dconf/db/gdm.d/<var>01-screensaver</var></file>:</p>
  <code>[org/gnome/desktop/screensaver]
picture-uri='file://<var>/opt/corp/background.jpg</var>'</code>
  <p>Replace <var>/opt/corp/background.jpg</var> with the path to
  the image file you want to use as the lock screen background.</p>
  <p>Supported formats are PNG, JPG, JPEG, and TGA. The image will be scaled if
  necessary to fit the screen.</p>
  </item>
  <include href="dconf-snippets.xml"
      xpointer="xpointer(/*/*[@xml:id='dconf-update'])"
      xmlns="http://www.w3.org/2001/XInclude"/>
  <item><p>You must log out before the system-wide settings take effect.</p>
  </item>
</steps>

<p>Next time you lock the screen, the new lock screen shield will show in the
background. In the foreground, time, date and the current day of the week will
be displayed.</p>

<section id="troubleshooting-background">
  <title>What if the background does not update?</title>

  <p>Make sure that you have run the <cmd its:translate="no">dconf update</cmd>
  command to update the system databases.</p>

  <p>In case the background does not update, try restarting <sys>GDM</sys>.
  <!-- For more information see <link xref="gdm-restart" />.--></p>
</section>

</page>