Categories

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+ + <authorblurb> +

+ </authorblurb> +

You can associate any ACS Object with one or more categories. In this tutorial we'll show how to equip your application with user interface to take advantage of the Categories service. -

We'll start by installing the Categories service. Go to /acs/admin and install it. This step won't be necessary for the users of your applications because you'll create a dependency with the Package Manager which will take care that the Categories service always gets installed when your application gets installed. -

Now that we have installed the Categories service we can proceed to modifying our application so that it can take advantage of it. We'll do it in three steps: -

The Categories service provides a mechanism to associate one or more category trees that are relevant to your application. One example of such tree is a tree of @@ -26,20 +31,25 @@ can take advantage of the Categories service there needs to be a way for administrators of your application to choose which category trees are applicable for the application. -

The way to achieve this is is to provide a link to the Category Management pages. Add the following snippet to your - /var/lib/aolserver/$OPENACS_SERVICE_NAME/packages/myfirstpackage/www/admin/index.tcl + /var/lib/aolserver/$OPENACS_SERVICE_NAME/packages/myfirstpackage/www/admin/index.tcl file: -

+          
+           		  set category_map_url [export_vars -base "[site_node::get_package_url -package_key categories]cadmin/one-object" { { object_id $package_id } }]
-          

+

and the following snippet to your - /var/lib/aolserver/$OPENACS_SERVICE_NAME/packages/myfirstpackage/www/admin/index.adp + /var/lib/aolserver/$OPENACS_SERVICE_NAME/packages/myfirstpackage/www/admin/index.adp file: -

+          
+              	          <a href="@category_map_url@">#categories.Site_wide_Categories#</a>
-          
The link created by the above code (category_map_url) 
+

The link created by the above code (category_map_url) will take the admin to the generic admin UI where he can pick category trees that make sense for this application. The same UI also includes facilities to build and edit @@ -61,7 +71,8 @@ form builder to note-edit.tcl. To achieve this we'll need to use the -extend switch to the ad_form command. Here's the "meat" of the - note-edit.tcl page:

+          note-edit.tcl page:
+           			# extend the form to support categories
 			set package_id [ad_conn package_id]
 			    
@@ -81,15 +92,18 @@
         				ad_returnredirect "."
         				ad_script_abort
     			}
-			
While the category::ad_form::add_widgets proc is taking 
+

While the category::ad_form::add_widgets proc is taking care to extend your form with associated categories you need to ensure that your items are mapped to the corresponding category object yourself. Also since the categories package knows nothing from your objects you have to keep the acs_named_objects table updated with any changes taking place. We use the items title so that they are listed in the categories browser by title.

Make sure that you also delete these entries if your item is delete. Add this to - your corresponding delete page:

+ your corresponding delete page:

 			db_dml delete_named_object "delete from acs_named_objects where object_id = :item_id"
-

note-edit.tcl requires a +

note-edit.tcl requires a note_id to determine which record should be deleted. It also looks for a confirmation variable, which should initially be absert. If it is absent, we create a form to @@ -101,7 +115,11 @@ note_id and confirm_p. If confirm_p is present, we delete the record, set redirection back to the index, and abort -script execution.

The database commands:

[$OPENACS_SERVICE_NAME@yourserver www]$ emacs note-delete.xql

<?xml version="1.0"?>
+script execution.
+
+      The database commands:
+      [$OPENACS_SERVICE_NAME@yourserver www]$ emacs note-delete.xql
+      <?xml version="1.0"?>
 <queryset>
   <fullquery name="do_delete">
     <querytext>
@@ -113,29 +131,41 @@
       select samplenote__name(:note_id)
     </querytext>
   </fullquery>
-</queryset>
And the adp page:
[$OPENACS_SERVICE_NAME@yourserver www]$ emacs note-delete.adp
+</queryset>
+      And the adp page:
+      [$OPENACS_SERVICE_NAME@yourserver www]$ emacs note-delete.adp
+       <master>
 <property name="title">@title@</property>
 <property name="context">{@title@}</property>
 <h2>@title@</h2>
 <formtemplate id="note-del-confirm"></formtemplate>
-</form>
The ADP is very simple.  The
+</form>

The ADP is very simple. The formtemplate tag outputs the HTML form generated by the ad_form command with the matching name. Test it by adding the new files in the APM and then deleting a few - samplenotes.

We will now make categories optional on package instance level and + samplenotes.
+

We will now make categories optional on package instance level and also add a configuration page to allow the package admin to enable/disable categories for his package. -

Go to the APM and create a number parameter with the name "EnableCategoriesP" - and the default value "0".

Add the following lines to your index.tcl:

+ 		  
+ 		  Go to the APM and create a number parameter with the name "EnableCategoriesP" 
+ 		  and the default value "0".
+ 		  Add the following lines to your index.tcl:
+ 		             set return_url [ns_conn url]
           set use_categories_p [parameter::get -parameter "EnableCategoriesP"]
-          
Change your to this:
+          
+          Change your to this:
+           			<a href=configure?<%=[export_vars -url {return_url}]%>>Configure</a>
 			<if @use_categories_p@>
    			<a href="@category_map_url@">#categories.Site_wide_Categories#</a>
    			</if>
-          
Now create a configure page
+          
+          Now create a configure page
+                     	ad_page_contract {
     			This page allows an admin to change the categories usage mode.
 			} {
@@ -160,41 +190,51 @@
         			ns_returnredirect $return_url
     			}
 			}
-           
and add this to its corresponding ADP page
+           
+           and add this to its corresponding ADP page
+                      	<master>
 			<property name="title">@title@</property>
 			<property name="context">@context@</property>
 
 			<formtemplate id="categories_mode"></formtemplate>
-	      
Reference this page from your admin page
+	      
+		Reference this page from your admin page
+		 		#TCL:
 		set return_url [ad_conn url]
 
 		#ADP:
 		<a href=configure?<%=[export_vars -url {return_url}]%>>Configure</a>
-		
Change the note-edit.tcl:
+		
+		Change the note-edit.tcl:
+		 		# Use Categories?
 		set use_categories_p [parameter::get -parameter "EnableCategoriesP" -default 0]
 		if { $use_categories_p == 1 } {
 			# YOUR NEW FORM DEFINITION
 		} else {
     		# YOUR OLD FORM DEFINITION
 		}
-

You can filter your notes using categories. The below example does not support multiple + +

You can filter your notes using categories. The below example does not support multiple filters and displays a category in a flat format.

The first step is to define the optional parameter category_id for - index.tcl:

+ 	  index.tcl:
+ 	    	  	ad_page_contract {
   		YOUR TEXT
 		} {
 			YOURPARAMS
     		{category_id:integer,optional {}}
 		}
- 	  
Now you have to check whether categories are enabled or not. If this is the case and a 
+

Now you have to check whether categories are enabled or not. If this is the case and a category id is passed you need to extend your sql select query to support filtering. One way would be to extend the mfp::note::get proc to support two more swiches -where_clause and - -from_clause.

+ 	  -from_clause.
+ 	    	  	set use_categories_p [parameter::get -parameter "EnableCategoriesP" -default 0]
 
 		if { $use_categories_p == 1 && $category_id ne "" } {
@@ -217,8 +257,10 @@
 		} else {
     		# OLD STUFF
 		}
- 	  
Also you need to make sure that the user can see the corresponding categories. Add the following 
- 	  snippet to the end of your index page:
+ 	  
+ 	  Also you need to make sure that the user can see the corresponding categories. Add the following 
+ 	  snippet to the end of your index page:
+ 	    	  # Site-Wide Categories
 		if { $use_categories_p == 1} {
     		set package_url [ad_conn package_url]
@@ -250,7 +292,9 @@
         		set tree_name [category_tree::get_name $tree_id]
     		}
 		}
-		
and to the corresponding index ADP page:
+		
+		and to the corresponding index ADP page:
+		 		<if @use_categories_p@>
  			<multiple name="categories">
            		<h2>@categories.tree_name@
@@ -259,12 +303,17 @@
            		</group>
          	</multiple>
 		<a href="@package_url@view?@YOURPARAMS@">All Items</if>
- 	  
Finally you need a an index.vuh in your 
- 	  www folder to rewrite the URLs correctly, the section called “Using .vuh files for pretty urls”:
+ 	  
+ 	  Finally you need a an index.vuh in your 
+ 	  www folder to rewrite the URLs correctly, the section called “Using .vuh files for pretty urls”:
+ 	    	  set url /[ad_conn extra_url]
 
 	  if {[regexp {^/+cat/+([^/]+)/*} $url ignore_whole category_id]} {
               rp_form_put category_id $category_id
 	  }
 	  rp_internal_redirect "/packages/YOURPACKAGE/www/index" 	  
- 	  
Now when ever the user select a category only notes that belong to this category are displayed.

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+ +

Now when ever the user select a category only notes that belong to this category are displayed.