Thanks to everybody who could help me !!
Since 3 days i'm trying to extract a color parameter without success.
I have a child theme of cassiopeia named cassiopeia_lolo installed by default. (Yellow star activated)
I implemented 3 color picker to change colors of website from admin. It's works fine.
I would like to display these color on theme admin to see the result and have an overview (aperçu) when changing the colors. So i need to access to color params from admin.
The skull and background skull have take the color picker colors
In the templateDetails.xml front site file i call the file /templates/cassiopeia_lolo/admin/style.php with that line :
<description>TPL_CASSIOPEIA_XML_DESCRIPTION<![CDATA[<link rel="stylesheet" type="text/css" href="../../templates/cassiopeia_lolo/admin/style.php" />]]></description>
but when the script style.php is loaded and i unncomment the following line of style.php it's don't works , the end of style.php is not loaded :
//$myTemplate = $app->getTemplate(true);
when i was using an other method (without using style.php) after this line who load the default template in a variable there is an php error saying "the template cassiopeia_lolo was not found.
Here are my files sorry if it's not very clear i will be happy to explain better the problem.
templates/cassiopeia_lolo/index.php
<?php /*defined( '_JEXEC' ) or die( 'Restricted access' );
use Joomla\CMS\Factory;
use Joomla\CMS\HTML\HTMLHelper;
use Joomla\CMS\Language\Text;
use Joomla\CMS\Uri\Uri;*/
/** @var Joomla\CMS\Document\HtmlDocument $this */
/*$app = Factory::getApplication();
$wa = $this->getWebAssetManager();*/
$header_footer_color = $this->params->get('backgroundcolor', '#eee');
$logocolor = $this->params->get('logocolor', '#eee');
$logocolor2 = $this->params->get('logocolor2', '#eee');
?>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
xml:lang="<?php echo $this->language; ?>" lang="<?php echo $this->language; ?>"
xmlns="http://www.w3.org/1999/xhtml"
xmlns:og="http://ogp.me/ns#"
xmlns:fb="https://www.facebook.com/2008/fbml">
<head>
<jdoc:include type="head" />
<?php include('templates/'. $this->template. '/color.php');?>
<link rel="stylesheet" href="<?php echo $this->baseurl ?>/templates/system/css/system.css" type="text/css" />
<link rel="stylesheet" href="<?php echo $this->baseurl ?>/templates/system/css/general.css" type="text/css" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<!--<link rel="stylesheet" href="<?php echo $this->baseurl ?>/templates/<?php echo $this->template; ?>/css/template.css?t=<? echo date(); ?>" type="text/css" />-->
<link rel="stylesheet" href="<?php echo $this->baseurl ?>/templates/<?php echo $this->template; ?>/css/template.css" type="text/css" />
<link rel="stylesheet" href="<?php echo $this->baseurl ?>/templates/<?php echo $this->template; ?>/css/template-mobile.css" type="text/css" media="all" />
<link rel="shortcut icon" href="<?php echo $this->baseurl ?>/templates/<?php echo $this->template; ?>/favicon.ico" />
<meta property="fb:app_id" content="171211871403248" />
<style type="text/css">
</style>
</head>
<body>
<div class="main" id="mainCont">
<!--Site-->
<div class="header" >
<jdoc:include type="modules" name="Header" />
<div class="navig">
<a href="<?php echo $this->baseurl ?>">
<div id="samy"><?php include('templates/'. $this->template. '/samy.php');?></div>
</a>
<a href="<?php echo $this->baseurl ?>/administrator"><div id="roue"></div></a>
<jdoc:include type="modules" name="Nav" />
</div>
</div>
<div class="banner">
<jdoc:include type="modules" name="Banner">
<div id="logo"></div>
</div>
<div class="mobile-top">
<div class="superdiv">
<div class="div1">
<a href="https://m.facebook.com/velorution.toulouse/?locale2=fr_FR"><img src="images/facebook.png"></a>
</div>
<div class="div2">
<a href="https://velorution-toulouse.org"><img src="images/samy5.png"></a>
</div>
<div class="div3">
<div class="burger2">
<div class="burger">
<span></span>
</div>
</div>
</div>
</div>
<div class='mobile'>
<div class="hamburger-overlay"></div>
<div class="mobile-content"></div>
</div>
</div>
<div class="content">
<div class="avant">
<jdoc:include type="component" name="Flash" />
<div class="component">
<jdoc:include type="component" />
</div>
<div id="sidebar">
<jdoc:include type="modules" name="Sidebar" />
</div>
</div>
</div>
<div class="footer">
<div class="samy-logo-container">
</div>
<div class="bluefoot"></div>
<jdoc:include type="modules" name="Footer" />
</div>
</div>
<script src="/templates/cassiopeia_lolo/app-1.0.js"></script>
</body>
</html>
My file templates/cassiopeia_lolo/admin/style.php
<?php
define('_JEXEC', 1);
define('JPATH_BASE', __DIR__ . '/../../..');
require_once JPATH_BASE . '/includes/defines.php';
require_once JPATH_BASE . '/includes/framework.php';
// Boot the DI container.
$container = \Joomla\CMS\Factory::getContainer();
// UPDATED alias the session service key to the web session service.
$container->alias('session.web', 'session.web.site')
->alias('session', 'session.web.site')
->alias('JSession', 'session.web.site')
->alias(\Joomla\CMS\Session\Session::class, 'session.web.site')
->alias(\Joomla\Session\Session::class, 'session.web.site')
->alias(\Joomla\Session\SessionInterface::class, 'session.web.site');
$app = $container->get(\Joomla\CMS\Application\SiteApplication::class);
//$myTemplate = $app->getTemplate(true);
//$params = $myTemplate->params;
header("Content-Type:text/css; charset=UTF-8");
header("Cache-Control:must-revalidate");
?>
:root{
--lolocolor: <?php echo $params->get('backgroundcolor');?>;
}
templates/cassiopeia_lolo/templateDetails.xml
<?xml version="1.0" encoding="utf-8"?>
<extension type="template" client="site">
<name>cassiopeia_lolo</name>
<version>1.0</version>
<creationDate>septembre 2022</creationDate>
<author>Super Utilisateur</author>
<authorEmail>contact@velorution-toulouse.org</authorEmail>
<copyright>(C) 2017 Open Source Matters, Inc.</copyright>
<description>TPL_CASSIOPEIA_XML_DESCRIPTION<![CDATA[<link rel="stylesheet" type="text/css" href="../../templates/cassiopeia_lolo/admin/style.php" />]]></description>
<positions>
<position>Header</position>
<position>Nav</position>
<position>Banner</position>
<position>Component</position>
<position>Sidebar</position>
<position>Footer</position>
</positions>
<config>
<fields name="params">
<fieldset name="advanced" addfieldpath="/administrator/components/com_apercu/models/fields">
<field name="Aperçu" type="Apercu" label="TPL_CASSIOPEIA_APERCU" description="TPL_CASSIOPEIA_APERCU_DESC"/>
<field name="backgroundcolor" type="color" default="#eee" format="rvba"
label="TPL_CASSIOPEIA_COLOR_HEADER"
description="TPL_CASSIOPEIA_FIELD_HEADER_BACKGROUND_COLOR_DESC" />
<field name="logocolor" type="color" default="#eee" format="rvba"
label="TPL_CASSIOPEIA_LOGO_COLOR"
description="TPL_CASSIOPEIA_LOGO_COLOR_DESC" />
<field name="logocolor2" type="color" default="#eee" format="rvba"
label="TPL_CASSIOPEIA_LOGO_COLOR2"
description="TPL_CASSIOPEIA_LOGO_COLOR2_DESC" />
<field name="brand" type="radio" label="TPL_CASSIOPEIA_BRAND_LABEL" default="1" layout="joomla.form.field.radio.switcher" filter="boolean">
<option value="0">JNO</option>
<option value="1">JYES</option>
</field>
<field name="logoFile" type="media" default="" label="TPL_CASSIOPEIA_LOGO_LABEL" showon="brand:1"/>
<field name="siteTitle" type="text" default="" label="TPL_CASSIOPEIA_TITLE" filter="string" showon="brand:1"/>
<field name="siteDescription" type="text" default="" label="TPL_CASSIOPEIA_TAGLINE_LABEL" description="TPL_CASSIOPEIA_TAGLINE_DESC" filter="string" showon="brand:1"/>
<field name="useFontScheme" type="groupedlist" label="TPL_CASSIOPEIA_FONT_LABEL" default="0">
<option value="0">JNONE</option>
<group label="TPL_CASSIOPEIA_FONT_GROUP_LOCAL">
<option value="media/templates/site/cassiopeia/css/global/fonts-local_roboto.css">Roboto (local)</option>
</group>
<group label="TPL_CASSIOPEIA_FONT_GROUP_WEB">
<option value="https://fonts.googleapis.com/css2?family=Fira+Sans:wght@100;300;400;700&display=swap">Fira Sans (web)</option>
<option value="https://fonts.googleapis.com/css2?family=Noto+Sans:wght@100;300;400;700&family=Roboto:wght@100;300;400;700&display=swap">Roboto + Noto Sans (web)</option>
</group>
</field>
<field name="noteFontScheme" type="note" description="TPL_CASSIOPEIA_FONT_NOTE_TEXT" class="alert alert-warning"/>
<field name="colorName" type="filelist" label="TPL_CASSIOPEIA_COLOR_NAME_LABEL" default="colors_standard" fileFilter="^custom.+[^min]\.css$" exclude="^colors.+" stripext="true" hide_none="true" hide_default="true" directory="media/templates/site/cassiopeia/css/global/" validate="options">
<option value="colors_standard">TPL_CASSIOPEIA_COLOR_NAME_STANDARD</option>
<option value="colors_alternative">TPL_CASSIOPEIA_COLOR_NAME_ALTERNATIVE</option>
</field>
<field name="fluidContainer" type="radio" layout="joomla.form.field.radio.switcher" default="0" label="TPL_CASSIOPEIA_FLUID_LABEL">
<option value="0">TPL_CASSIOPEIA_STATIC</option>
<option value="1">TPL_CASSIOPEIA_FLUID</option>
</field>
<field name="stickyHeader" type="radio" label="TPL_CASSIOPEIA_STICKY_LABEL" layout="joomla.form.field.radio.switcher" default="0" filter="integer">
<option value="0">JNO</option>
<option value="1">JYES</option>
</field>
<field name="backTop" type="radio" label="TPL_CASSIOPEIA_BACKTOTOP_LABEL" layout="joomla.form.field.radio.switcher" default="0" filter="integer">
<option value="0">JNO</option>
<option value="1">JYES</option>
</field>
</fieldset>
</fields>
</config>
<files>
<filename>templateDetails.xml</filename>
</files>
<media folder="media" destination="templates/site/cassiopeia_lolo">
<folder>css</folder>
<folder>js</folder>
<folder>images</folder>
<folder>html</folder>
<folder>scss</folder>
</media>
<inheritable>0</inheritable>
<parent>cassiopeia</parent>
</extension>
