Fields and Field Groups
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Revision as of 12:43, 26 April 2022 by Ceford (Finished)
Fields are used to display additional attributes of Articles, Contacts or Users. The data are entered in an Administrator Edit form and displayed in the Site. An example:
Suppose you write articles about aspects of nature, sometimes Flowers, sometimes Animals. One field you might wish to record and display for both is the Latin Name, requiring a text field. Another might be Habitat: Woodland, Pond, Meadow, and so on, requiring a drop-down list. For flowers you may wish to record Flowering Season using 4 checkboxes, one for each season, or 12 checkboxes, one for each month.
Empty fields in the input form are not displayed in the Site output, so you could keep all fields in one long list. However it is usually better to use categories for your Articles, say Flowers and Animals. Fields can be assigned to more than one Category. So Latin Name and Habitat fields would be assigned to both but Flowering Season would only be assigned to the Flowers category.
If a field is not assigned to a group it will appear in the Edit form in a Fields tab. If a field is assigned to a group it will appear in a tab with that name. So for the Flowers group it seems appropriate to create a group named Flower Data (or just Flowers, although using the same name for different things gets confusing). And for the other common fields you could use a Nature group.
A Worked Example - Garden Life
Before working with fields, this example sets up Article Categories to make it simple to create Category Blog or List layouts for Nature, the parent Category or any one of Birds, Flowers, Mammals or Trees. Creepy-crawlies have wriggled off the bottom of the screenshot!
Some obvious features of Nature to note:
- All of the items have Common names and Latin Names.
- Flowers and Trees have a Flowering Season, Height and Spread but Birds and Mammals do not.
- Birds have Wingspan, and Length whilst Mammals have Height and Length.
The point here is that it may be necessary to set up Fields OR Field Groups for common features, such as Latin Name, and separate Field Groups for each category of nature.
Creating Field Groups for Articles is very simple: Select Content → Field Groups from the Administrator menu and select the New button in the toolbar. Enter a suitable Title and select Save & Close from the toolbar. The illustration below shows the Field Groups list with two groups created.
To create a new article Field select Content → Fields from the Administrator menu and fill in the form. Some examples are illustrated below.
Text - Latin Name
Note in the screenshot that this field has not been assigned to a Field Group but it has been assigned to the Nature category. This should ensure that it always appears in articles in the Nature category or any sub-category.
Checkboxes - Flowering Season
Checkboxes appear in the Article Edit form for you to tick to select the flowering season. In the article display only those with a tick will be listed. For example, if you tick Spring and Summer the output will show Flowering Season: Spring, Summer.
Note that in this screenshot the Field has been assigned to the Flowers group and to the Flowers Category. That should ensure that the field is only present in articles bout flowers.
Color - Colour
Just to be confusing, the name of the field type is Color (US Spelling) but the label in documentation is Colour (British Spelling).
And possibly even more confusing, the colour is actually selected in the article edit form:
Integer - Hardiness
The hardiness of a plant is an integer from 1 to 10. There is no field for a real number so length and height have to be integers with the scale (cm or m or ft) included in the label. If there is no obvious upper limit then leave the Last: field empty.
Article Edit Form
When an Articles: New form is opened the default Category is Uncategorised and the form tabs do not include Fields and Flowers. Select the Flowers category and the form is reloaded with those tabs present.
The Fields tab contains fields that were not included in a Field Group. Enter data as appropriate. Example:
The Flowers tab contains fields included in that Field Group. Enter data as appropriate. It is shown above in the Color - Colour section.
Take a look at the result seen in your site. In this example the article was marked as Featured so it appears on the site Home page:
Not what you were expecting? You could go back to the Field edit form and set some Display Options. You will need to know some CSS and add code to user.css in your site template. In this example some dummy values have been added to the options:
<ul class="fields-container"> <li class="field-entry common-name my-label"> <span class="field-label my-output">Common Name: </span> <span class="field-prefix">my-prefix</span> <span class="field-value my-value">Saxifrage</span> <span class="field-suffix">my-suffix</span> </li> <li class="field-entry latin-name "> <span class="field-label ">Latin Name: </span> <span class="field-value ">Saxifraga - Peter Pan</span> </li> <li class="field-entry flowering-season "> <span class="field-label ">Flowering Season: </span> <span class="field-value ">Autumn, Winter</span> </li> <li class="field-entry colour "> <span class="field-label ">Colour: </span> <span class="field-value ">#fa9bab</span> </li> <li class="field-entry height "> <span class="field-label ">Height: </span> <span class="field-value ">10</span> </li> <li class="field-entry spread "> <span class="field-label ">Spread: </span> <span class="field-value ">30</span> </li> <li class="field-entry hardiness "> <span class="field-label ">Hardiness: </span> <span class="field-value ">5</span> </li> </ul>
More in another tutorial?