View source for X2Model and Dynamic Fields

[[Category:Development]]

= Introduction =

Typically in Yii, when a model (see: [[yii:CActiveRecord|CActiveRecord]]) is used to retrieve data from a table in the database, the model's attributes are simply inherited from the schema for that table. However, in order to provide the means to add and remove fields from models (and thus from database tables), in addition to providing more advanced options for setting behaviors of attributes, most of the model classes in X2EngineCRM (the ones that are associated with database tables) are extended from a class [[x2doc:X2Model|X2Model]]. The attributes of all such models are not derived from the database itself but from an attribute registry stored in the <tt>x2_fields</tt> table. The following columns in the fields table are of particular importance:

{|class="wikitable"
|-
! scope="col" | Column Name
! scope="col" | Description
|-
|modelName
|The exact name of the model class to which the field belongs, with only one exception (fields with modelName="Quotes" belong to class [[x2doc:Quote|Quote]])
|-
|fieldName
|The name of the database column
|-
|attributeLabel
|The attribute label (the name of the field as displayed in the UI)
|-
|modified
|Whether the field has been modified by the user.
|-
|custom
|Whether the field has been created by the user.
|-
|type
|The type of the column. This does not merely specify the canonical MySQL type, but is used for specifying advanced behaviors for the field.
|-
|required
|Specifies that the model attribute cannot be null or empty, if set to 1.
|-
|readOnly
|Signifies that the model attribute cannot be modified through user input, if set to 1.
|-
|linkType
|In the case that the field is being used as a link, keywords set in this field signify what type of link should be generated in output.
|-
|searchable
|If set to 1, the field's contents are included in global searches through records.
|-
|relevance
|An integer value used for sorting search results.
|-
|isVirtual
|If set to 1, the field does not actually correspond to a database column; rather, it is an ephemeral attribute of the model that is used for passing data from the view to the controller and vice-versa. For instance, it would be used in the case of input that needs to be collected as part of the model (initially) so that it can be put through input validation.
|}

= Field Types =
The types of fields, as mentioned before, are not canonical MySQL data types, but rather keywords for specifying how they are to be treated and rendered, and that includes the allowable types that the field may be. When rendering an attribute, X2Model and its subclasses use [http://doc.x2engine.com/class-X2Model.html#_renderAttribute renderAttribute], wherein a <tt>case</tt> statement is used to distinguish between field types and choose a method of displaying the field.

;assignment
: The attribute is rendered as a link using [//doc.x2engine.com/class-User.html#_getUserLinks User::getUserLinks]. The input field for it is a dropdown list of users and groups.
;boolean 
: (<tt>TINYINT</tt>) Self-explanatory; true or false.
;currency
: (<tt>FLOAT</tt>) A currency value. Setting a field to this type enables printing currency symbols by values.
;date
: (<tt>INT</tt>) Date, as a Unix timestamp. Using this type for an integer field ensures it will effectively be treated as a Unix timestamps and converted to a full date when rendered.
;dropdown
: (<tt>VARCHAR</tt>) Specifies the ID of a list of items stored in <tt>x2_dropdowns</tt> to use as the permissible values for the field.
;email
: (<tt>VARCHAR</tt>) Specifies that the contents are formatted like (and correspond to an actual) email address.
;int
: (<tt>INT</tt>) Self-explanatory
;link
: (<tt>VARCHAR</tt>) If the field content is an integer, this field specifies another record that it is linked to / associated with (and the model is specified by <tt>linkType</tt>), and thus the rendered field will be a link to the view of that record. If it is text, it is treated as a URL and simply rendered.
;phone
: (<tt>VARCHAR</tt>) Field is a phone number and should be treated/formatted as such when formatting for output.
;rating
: (varies) The CStarRating widget should be used to format this field in output.
;text
: (<tt>TEXT</tt> or <tt>VARCHAR</tt>) Distinct from VARCHAR in that links within the field's data are automatically transformed using [http://doc.x2engine.com/class-x2base.html#_convertUrls x2base::convertUrls].
;url
: (<tt>VARCHAR</tt>) Field is a URL
;varchar
: (<tt>VARCHAR</tt>) Self-explanatory.
;visibility
: (<tt>INT</tt>) If 1, the record's contents are public. If 0, it is private. If 2, the record is visible only to the user's groups.

= Linking back to a record in child classes =
Relevant documentation: [[yiiguide:basics.component#component-behavior|Component Behavior]]

In cases where <tt>link</tt> and <tt>linkType</tt> are used, [[x2doc:X2LinkableBehavior|X2LinkableBehavior]] comes into play; X2Model inherits the behaviors and attributes from that class, since it is attached as a behavior. The method <tt>getLink</tt> is used for generating controller routes. In this method, it is assumed that the model has the same name as the controller/module. Thus, for every module/controller, the models used by them have the same names, with few exceptions. In the case of any new model that is a child class of X2Model, for which the class does not follow these naming conventions, the following steps will be necessary:

* Override the <tt>behaviors()</tt> method so that the subclass does not have <tt>X2LinkableBehavior</tt>; have it return an empty array or an array with other desired behaviors
* Manually set the following attributes:
*;<tt>baseRoute</tt> 
*: The route prior to any actions; may contain a module and/or a controller ID.
*;<tt>viewRoute</tt>
*: The route (before adding the ID as a GET parameter) used for viewing records.
*;<tt>autoCompleteSource</tt>
*: The route that will be used for querying auto-complete results for use in auto-completion fields.
* Create a <tt>getLink</tt> method in the child class that generates the actual link markup.