Topics allow for flexible free format data, sometimes you want to ensure strucutre to some of the topic information, this can be done with Forms e.g. saying what type of topic it is (Bug, Feature, FAQ entry etc).
- 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 zero or more 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 rowsxcols 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)
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.
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 an Add Form
button appears at the end of the topic. If a form is present a Change
button appears in the top row of the form to the right of the form name. The buttons leads to a screen that enables no form
to be selected of one of those specified by
A default form template (i.e. new topics get this default form) can be provided by creating the
topic in a Web and adding a form to it. Initial form values can be set here.
Addtionaly a new topic can be given a form using the
parameter in the URL. Initial values can then be provided in the URLs or as form values. Names being:
- Not checkboxs - nameFLD e.g. ?BugPriorityFLD=1
- Checkbox - nameFLDvalue=1 e.g. ?ColourFLDRed=1. Note that all boxes with a tick must be specified.
Defining 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.
Defining form in one topic
Example: WebFormTemplate of the TWiki.Know web:
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
- WebFormTemplate of the TWiki.Know web:
- TopicClassification topic:
- This format allows you to define field items with / without WikiNames, depending on your needs.
- The topic can be protected in the usual manner so that not everybody can change the form template - see TWikiAccessControl
... 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 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 topic definition is not read when a topic is viewed
Changes from category system
Main changes from TWikiCategoryTable
- Name changed in the hope that form is more readily understandable than category
- 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
- The UseCategory radio button has gone, the replacement being the Change form and Add Form buttons.
Creating new topics with forms
When you create a new topic in a web that has the WEBFORMS preferences variable set you will get a Add Form
button at the bottom of the page. However, if the WebTopicEditTemplate
topic has had a form added this will appear with values set; Change
in the form can be pressed to remove the template or switch to a different one.
A form embedded in a topic can also cause a form to be present in a new topic, this is done by specifying the
parameter in the URL.
Topic meta data
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
WEBFORMS variable defines possible 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.
defines the categories and is used in the conversion. The form template must be put as first item in WebPreferences
. If it's not present
results in an oops
dialog results. If things aren't working correctly there may be entries
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.
- 16 Aug 2001