Default_Bootstrap overrides Admin_Bootstrap - zend-framework

Question

In the Admin module installation Layout and Navigation of Default module
application/modules/default/Bottstrap.php
<?php
class Default_Bootstrap extends Zend_Application_Module_Bootstrap
{
protected function _initNavigation()
{
$layout = Zend_Layout::startMvc()->setLayout('layout');
$config = new Zend_Config_Xml(APPLICATION_PATH.'/configs/navigation.xml','nav');
$navigation = new Zend_Navigation($config);
Zend_Registry::set('Zend_Navigation', $navigation);
}
}
application/modules/admin/Bottstrap.php
<?php
class Admin_Bootstrap extends Zend_Application_Module_Bootstrap
{
protected function _initNavigation()
{
$layout = Zend_Layout::startMvc()->setLayout('admin');
$config = new Zend_Config_Xml(APPLICATION_PATH.'/configs/navadmin.xml','nav');
$navigation = new Zend_Navigation($config);
Zend_Registry::set('Zend_Navigation', $navigation);
}
}
application/configs/application.ini
;Modules
resources.frontController.moduleDirectory = APPLICATION_PATH "/modules"
resources.frontController.defaultModule = "default"
resources.modules[] =
resources.frontController.actionhelperpaths.Default_Controller_Helper = APPLICATION_PATH "/modules/default/controllers/helpers"
;Layout
resources.layout.layoutpath = APPLICATION_PATH "/layouts"
;View
resources.view.doctype = "HTML5"
resources.view.encoding = "UTF-8"
resources.view.contentType = "text/html; charset=UTF-8"

Answer 1

In a single-module application, layout and navigation are typically initialized in the single app-level bootstrap (sometimes by reference to an application resource plugin).
However, in a multi-module application, all the module bootstraps will run. Therefore, the last one that runs ends up overriding all the others.
For these types of tasks that depend upon knowing which module has been requested, you can use a front-controller plugin with routeShutdown() hook. Each module X could register its own plugins for navigation and layout that check if the requested module matches X. If not, bail early. If so, perform your initialization.
See MWOP's article on the subject of module bootstrapping for more details:
http://mwop.net/blog/234-Module-Bootstraps-in-Zend-Framework-Dos-and-Donts

Answer 2

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