History: Linking trackers

            ! Linking Trackers
^This is ((Tutorial)), to show some of the possibilities of trackers using the field types which help linking content from one tracker to another through common fields. This is very much used in "Exchange networks" where goods, services and knowledge is exchanged without using money but direct exchange or through using ((Mod CC|Community currencies))^

We will create a tracker for Offers and another one for Demands, that include the option to allow comments. Both trackers will be linked by a common field (field user), which will allow showing information from one tracker on the other.

See also: ((Relations Tracker Field))


First we will create the one for Offers, for example, and its fields, and afterwards, we will create the one for Demands from duplicating the one for Offers. 

!!# Create the tracker "Offers"
You can do that through the main application menu, at "Trackers > Admin Trackers > Create tracker", with default values for all parameters, except for the setting to allow comments, that we will leave checked, and allowing the fields to be shown in the visualization mode.

!!# Create its fields 
Click where it says "__Edit This Tracker's Fields__".
::{img src=img/wiki_up/20_linking_trackers_01_.png}::

Create the following fields:
|| :: __Offers__ ''(Id Tracker = 1)''::
Id | Position | Name | Type | Options | isMain | Multilingual | Tbl vis | Searchable | Public | Hidden | Mandatory | Description
10 | 10 | Title | text field | | X | - | X | X | X | - | X | name of the offer
11 | 20 | Categories | category | 4 | | - | | X | X | - | X |
12 | 30 | User | user selector | 1 | X | - | | X | X | editable by admins | X |
13 | 40 | Demands of the same person | items list | ~~Coral: 2,16,~~~~green:12,~~~~Coral:14,1 | X | - | X | | X | - | |
||~~
!!# Create the tracker "Demands" (duplicate from "Offers")
Once created this tracker for Offers, we will duplicate it (through "Trackers > Admin Trackers > Edit tracker Offers > Duplicate tracker"), setting the new tracker as "Demands" and something as description, and choosing "Offers" as the tracker to duplicate it from.

!!# Edit its fields 
Once done, go to edit the required items so that the new tracker Demands becomes as this table below (change the field 14 description, field 17 "Demands of the same person" for "Offers of the same person", and as parameters, the new ones.

~~Coral:
|| :: __Demands__ ''(Id Tracker = 2)''::
Id | Position | Name | Type | Options | isMain | Multilingual | Tbl vis | Searchable | Public | Hidden | Mandatory | Description |
14 | 10 | Title | text field | | X | - | X | X | X | - | X | name of the demand
15 | 20 | Categories | category | 4 | | - |  | X | X | - | X |
16 | 30 | User | user selector | 1 | X | - |  | X | X | editable by admins | X |
17 | 40 | Offers of the same person | items list ~~| ~~green: 1,12,~~~~Coral:16,~~~~green:10,1 | X | - | X | | X | - | |
||
~~

!!! How to fill the field "items list" from the Offers Tracker
~~green:How to fill the field "items list" from the Offers Tracker (Id Tracker 1) with 5 parameters or options separated by commas~~:

|| Id Tracker (There) | Id Common Field at the other tracker | Id Common Field at this tracker | Id Field that we want to show (of the tracker in there) | linked
~~Coral: 2 (Tracker Demands) ~~ | ~~Coral: 16 (field "user" at tracker Demands) ~~ | ~~green: 12 (field "user" at tracker Offers) ~~ | ~~Coral:14 (field "Title" of the Demand at the Demands tracker) ~~ | 1 (make the information shown in this field at the Offers tracker as clicable, in order to allow going directly to those items in the Demands tracker)||

!!! How to fill the field "items list" of the Demands Tracker
~~Coral:How to fill the field "items list" of the Demands Tracker (Id Tracker 2) with 5 parameters or options, separated by commas~~:

|| Id Tracker (There) | Id Common Field at the other tracker | Id Common Field at this tracker | Id Field that we want to show (of the tracker in there) | linked
~~green: 1 (Tracker Offers)~~ | ~~green:12 (field "user" at tracker Offers) ~~ | ~~Coral: 16 (field "user" at tracker Demands) ~~ | ~~green: 10 (field "Title" of the Offer of the Offers tracker) ~~ | 1 (make the information shown in this field at the Demands tracker as clicable, in order to allow going directly to those items in the Offers tracker)||

!!! Allow selecting many options for categories
For the field Category, some option will show up, which will alow selecting one or more than one). These options have to be created as a subcategories of a parent category. 

For example, imagine that we have the category 1 that is "Categorisation of offers and demands", and that we create inside, some child categories, like the subcategories "Courses" (with id of category automatically assigned to 2 in that case), "Services" (with id automatically assigned to 3), "Objects" (with id automatically assigned to 4), and "Other" (with id automatically assigned to 5).

It is necessary to write the value "1" to the field category (in order to show the subcategories that category 1 contains).

!!# Fill in some Offers and Demands
Now you are ready to fill some offers as a different users (for example, user1 inserts two offers and a demand, and user2 inserts 1 offer and 3 demands). And afterwards see how it behaves... :-)
---

We have also enabled the option that these trackers allow comments (when we created the tracker, or afterwards through editing it again, if needed, in order to set that both trackers allows comments). 

You can also test to watch to any tracker (click on the eye to subscribe in order to receive emails when there are new items added or modified to the tracker), and to watch any specific item of any of those trackers (to receive email notifications when there are comments on this item, or there are changes to it).

You can see similar trackers in action at http://intercanvis.net

!!# Customize the tracker interfaces through wiki plugins
You can customize the user interface to list, add or search items through plugins.

You can see some examples in action at:
http://intercanvis.net/Ofertes

http://intercanvis.net/Demandes

-=Related pages=-
* ((Tutorials))
* ((Trackers))
* [http://intercanvis.net/Welcome]