added Admin view updates to the init_app call, so users can add the admin view at that time.

flask_admin/base.py

 import os.path as op
-import warnings
 
 from functools import wraps
 
@@ -440,7 +439,7 @@ class AdminIndexView(BaseView):
         super(AdminIndexView, self).__init__(name or babel.lazy_gettext('Home'),
                                              category,
                                              endpoint or 'admin',
-                                             '/admin' if url is None else url,
+                                             url or '/admin',
                                              'static',
                                              menu_class_name=menu_class_name,
                                              menu_icon_type=menu_icon_type,
@@ -509,9 +508,6 @@ class Admin(object):
             name = 'Admin'
         self.name = name
 
-        self.index_view = index_view or AdminIndexView(endpoint=endpoint, url=url)
-        self.endpoint = endpoint or self.index_view.endpoint
-        self.url = url or self.index_view.url
         self.static_url_path = static_url_path
         self.subdomain = subdomain
         self.base_template = base_template or 'admin/base.html'
@@ -519,12 +515,32 @@ class Admin(object):
         self.category_icon_classes = category_icon_classes or dict()
 
         # Add predefined index view
-        self.add_view(self.index_view)
+        self._set_admin_index_view(index_view=index_view, endpoint=endpoint, url=url)
 
         # Register with application
         if app is not None:
             self._init_extension()
 
+    def _set_admin_index_view(self, index_view=None,
+                             endpoint=None, url=None):
+ 	    """
+ 	    	Add the admin index view.
+ 	    	
+           :param index_view:
+                Home page view to use. Defaults to `AdminIndexView`.
+            :param url:
+                Base URL
+            :param endpoint:
+                Base endpoint name for index view. If you use multiple instances of the `Admin` class with
+                a single Flask application, you have to set a unique endpoint name for each instance.
+ 	    """                            
+        self.index_view = index_view or AdminIndexView(endpoint=endpoint, url=url)
+        self.endpoint = endpoint or self.index_view.endpoint
+        self.url = url or self.index_view.url
+
+        # Add predefined index view
+        self.add_view(self.index_view)
+
     def add_view(self, view):
         """
             Add a view to the collection.
@@ -565,7 +581,7 @@ class Admin(object):
                 Link to add.
         """
         if link.category:
-            self.add_menu_item(link, link.category)
+            self._add_menu_item(link, link.category)
         else:
             self._menu_links.append(link)
 
@@ -585,15 +601,7 @@ class Admin(object):
         for link in args:
             self.add_link(link)
 
-    def add_menu_item(self, menu_item, target_category=None):
-        """
-            Add menu item to menu tree hierarchy.
-
-            :param menu_item:
-                MenuItem class instance
-            :param target_category:
-                Target category name
-        """
+    def _add_menu_item(self, menu_item, target_category):
         if target_category:
             cat_text = as_unicode(target_category)
 
@@ -611,10 +619,6 @@ class Admin(object):
         else:
             self._menu.append(menu_item)
 
-    def _add_menu_item(self, menu_item, target_category):
-        warnings.warn('Admin._add_menu_item is obsolete - use Admin.add_menu_item instead.')
-        return self.add_menu_item(menu_item, target_category)
-
     def _add_view_to_menu(self, view):
         """
             Add a view to the menu tree
@@ -622,12 +626,13 @@ class Admin(object):
             :param view:
                 View to add
         """
-        self.add_menu_item(MenuView(view.name, view), view.category)
+        self._add_menu_item(MenuView(view.name, view), view.category)
 
     def get_category_menu_item(self, name):
         return self._menu_categories.get(name)
 
-    def init_app(self, app):
+    def init_app(self, app, index_view=None,
+                 endpoint=None, url=None):
         """
             Register all views with the Flask application.
 
@@ -638,10 +643,16 @@ class Admin(object):
 
         self._init_extension()
 
+        self._views = []
+
         # Register views
         for view in self._views:
             app.register_blueprint(view.create_blueprint(self))
 
+        # Register Index view
+        self._set_admin_index_view(index_view=index_view, endpoint=endpoint, url=url)
+
+
     def _init_extension(self):
         if not hasattr(self.app, 'extensions'):
             self.app.extensions = dict()