Planning Your Data Model and Taxonomies

Hierarchical constants

What are hierarchical constants? Imagine some keywords allowing to quickly find items of interest --- you have a top-level keyword Country, a first-level keyword United Kingdom and a second-level keyword Leeds. The support has three parts: Editing of the constants and choosing them in the Add / Edit item in AA control panel is described here, using them in a search form is described elsewhere.

Hierarchical editor

The new hierarchical editor is accessible from the standard constant editor by the button "Edit in Hierarchical editor".

The standard and the hierarchical editor are in some sense interchangeable --- you can edit constants in both and it will not damage the structure.

The hierachical editor shows several level boxes. When you choose an item in some level, the next level box will be updated. Because usually the constant Name and Value are the same, there is a check box "Copy value from name" which allows you to only edit the Name box. You can change the editor view by the options at the bottom of the page:

• Hierarchical --- uncheck to get back to the standard constant editor,
• Hide value --- hide the value box, the value will be always copied from the name
• Levels horizontal --- should the level boxes be organized horizontal or vertical?
• Level count --- count of level boxes

Changes to the view setting will take effect only after using "Save all changes to database".

Input type "Hierarchical constants"

To take advantage of the constants ordered into a hierarchy, use the "Hierachical constants" input type for a field containing the constants. This view allows the user to go through the constants by level boxes in the same way as in the hierarchical constant editor. The values chosen are filled into a multiple-select-box field.

Check the "wizard with help" about parameters.