This is the view
createForm1 of
Products controller. Lookup field
CategoryID is configured as a radio button list. Each list item represents a row from
Categories lookup table. Items are sorted in an alphabetical order.
The data model of
Products controller is based on the table with the same name. A foreign key consisting of
CategoryID column is referencing
Categories table. Field
CategoryName is borrowed from
Categories table to be displayed as an alias of
Products.CategoryID.
If a dedicated model for
Categories table is created, then the app builder will produce a corresponding controller and configure
Products.CategoryID field as a lookup.
App builder will set
Items Data Controller property of
CategoryID field to "Categories",
Data Value Field to "CategoryID", and
Data Text Field to "CategoryName". Both fields are referencing the fields of the controller specified as a source of items.
Field
Items Data View property is left blank by default.
Categories will be ordered by CategoryName when selected from Categories table if Items Data View is not specified.
Set
Products / Fields / CategoryID / Items Data View to "grid1". This will force your app to take into account the sort expression of
Categories/views/grid1 view. If the sort expression is specified, then the items will be ordered accordingly.
You can set up sort order and sort type directly in the
Categories model. For example, you can configure the model to sort categories in descending order.
Alternatively, select
Categories/views/grid1 view and enter "CategoryName desc" without quotes in
Sort Expression property.
Generate the app and observe the new sort order of categories in the lookup.
Note that the custom sort order will also apply to any other style of lookup.
Consider adding a numeric column to Categories table to have a a data-driven custom sort order.