## Form Templates
%TOC%
### Background
This is a more general replacement for the [[TWikiCategoryTable]] capability, in particular Forms are defined by special topics, where as categories were defineind using special templates.
### Terminology
* **Form Template:** A set of fields defining a form. (_Class_ in OO speak; used to be called _category table definition_)
* A web may contain more then one form template.
* **Form:** A topic containing additional meta-data (besides the free form TEXTAREA) which categorizes the content. (_Object_ in OO speak; used to be called _category table_)
* A topic has zero or one of the defined forms. So there are topics with a form or without.
* **Form Field:** A named item in a form. (Used to be called _category item name_)
* **Field Type:** The type of a field when editing a form. The type defines the HTML INPUT tag widgets when editing a topic:
* **select:** Drop down box or selector
* **checkbox:** One or more check boxes
* **checkbox+buttons:** One or more check boxes, plus _set_ and _clear_ buttons to set/clear all check boxes
* **radio:** One or more radio buttons
* **text:** A one-line text field
* **textarea:** A general text area - size is _rows_x_cols_ e.g. 40x10
* **Field Value:** Value of a form field. Can be one or more values from a fixed set (select, checkbox, radio type) or free form (text type). (Used to be called _category item value_)
### Specification
#### Enable forms for a web
By default topics can be edited in free form. A form can be added to a topic to give it more structure. Forms are enabled on a per web basis. This can be done in two ways. One is similar to that used for the older category system, with this a Web can have only one form. The other allows a Web to have any number of forms.
A default form template can be provided by creating the **WebTopicEditTemplate**
topic in a Web and adding a form to it. Initial form values can be set here.
#### Enabling single default form
The **DEFAULTFORM**
variable in [[WebPreferences]] is optional. If present it specifies the default form for all topics in the Web. Every time you edit a topic you will be presented with a form. The form must contain the special field `UseForm` (analogous to the `UseCategory` line in the old category system). The values for this must be:
* First field - "Yes" (any capitalisation)
* Second field - any text, but must mean _no form_
#### Enabling multiple forms
The **WEBFORMS**
variable in [[WebPreferences]] is optional and defines a list of possible form templates e.g.
* Set WEBFORMS = BugForm, FeatureForm, BookLoanForm
With this present an extra button is added to the edit view. If the topic doesn't have a form the button appears at the end of the page. If a form is present the button appears in the top row of the form. Pressing the button leads to a screen that enables _no form_ to be selected of one of those specified by `WEBFORMS`.
#### Define a form template
Form templates are defined by topics, one topic per form template. A form template topic has descriptive text mixed with the form template definition in the form of a TWiki table.
### Examples
#### Defining form in one topic
Example: WebFormTemplate of the TWiki.Know web:
Name: |
Type: |
Size: |
Values: |
Tooltip message: |
Use Form? |
radio |
0 |
Yes, No |
Select 'No' to remove the form |
Topic Classification? |
select |
1 |
No Disclosure?, Public Supported?, Public FAQ? |
blah blah... |
Operating System? |
checkbox |
3 |
Os HPUX?, Os Linux?, Os Solaris?, Os Win? |
blah blah... |
Os Version? |
text |
16 |
|
blah blah... |
#### Defining form in multiple topics
The form template can also be defined in an alternative way by using more then one topic:
* A **form template topic** defines the form
* Values of fields that have more then one value, e.g. of type radio, select and checkbox can be defined by **field value template topics**
Above Example:
* WebFormTemplate of the TWiki.Know web:
Name: |
Type: |
Size: |
Values: |
Tooltip message: |
Use Form? |
radio |
0 |
Yes, No |
blah blah... |
Topic Classification? |
select |
1 |
|
blah blah... |
Operating System? |
checkbox |
3 |
|
blah blah... |
Os Version? |
text |
16 |
|
blah blah... |
* TopicClassification topic:
Name: |
Type: |
Tooltip message: |
No Disclosure? |
option |
blah blah... |
Public Supported? |
option |
blah blah... |
Public FAQ? |
option |
blah blah... |
#### Notes
* This format allows you to define field items with / without [[TWiki/WikiNames]], depending on your needs.
* The topic can be protected in the usual manner so that not everybody can change the form template.
* `...` can be used for force a link, at present `...` format is not supported
* The "Tooltip message:" column is used as a tool tip for the field name (only if field name is a [[TWiki/WikiName]]) - you only see the tooltip on edit
* The first item in the list is the default item. Alternative initial values can be given in a topic template such as **WebTopicEditTemplate**
or using fieldFLD=value or for checkboxes fieldFLDcheckbox=1 in URL
* The `UseForm` field is special.
* Will always default to second value (don't use form) when topic doesn't have a form
* Is not show on preview or view
* When set to no on save, form data is deleted.
* It is not a good idea to use both `DEFAULTFORM` and `WEBFORMS` [[WebPreferences]] in the same Web.
### Changes from category system
Main changes from [[TWikiCategoryTable]]:
* Name changed in the hope that form is more readily understandable than category
* `UseCategory` is now `UseForm`
* The templates for category view/edit have been dropped
* Forms are defined by topics, categories were defined in a template file
* A Web can have multiple forms, only one category was possible
* Form data is saved in meta variables - see [[MetaDataDefinition]], and render to HTML on viewing. Category data was stored as HTML
### Creating new topics with forms
When you create a new topic in a web that has the WEBFORM preferences variable set you will get a topic with the default form template specified by the variable.
For simplicity we should use the default form template when one creates a new topic by question mark link or "Go" field, i.e. better not to show a menu to select a form template.
### Topic meta data
See [[TWikiMetaDataDefinition]].
The form template topic name and all form fields/values are stored in the topic meta data. The form template topic name is needed for edit and save.
The order of form field/value items in the meta-data is the same as in the form template.
### UI for multiple form templates
* Optional **WEBFORMS**
variable defines possibles form templates that can be selected after pressing "Change" (forms) button on edit page
* A template topic can use any form template
* Decided not to ask user to choose a template or form template when creating a topic as goes against the KISS of Wiki systems.
* New topics with a form get instantiated by simple HTML forms asking for a topic name, i.e. there is a SubmitExpenseReport topic were you can create new expense reports, a SubmitVacationRequest topic and so on. These can specify the required template topic and hence form.
### Migration of Category information
Principle: new system should work with old data with no special conversion.
Old data should be transparently upgraded to the new meta format when a topic is edit/previewed/saved.
On upgrading the administrator must produce a form template topic for each Web that using the old category system. `twikicatitems.tmpl` defines the categories and is used in the conversion. The form template must be put as first item in [[WebPreferences]] variable **WEBFORM**
or **DEFAULTFORM**
(if/when put in). If it's not present, an _oops_ dialog results.
-- [[Main/JohnTalintyre]] - 07 Aug 2001