Editing the data model

Data model editor

You enter the data model editor by selecting "Data model" on the main screen of the application in Eximee Designer

Illustration 1. "Data model" tab of the low-code application

The data model editor is divided into three tabs:

• Structure, where we manage the model structure and fill in node parameters,

• Data sources, where we define and parameterize data sources,

• Source, where we edit the JSON that is the source representation of the model - functionality for advanced users.

If your application does not yet have a data model, you can create one by clicking the "Initialize data model" button.

Structure

The data model structure is presented as a tree in the left panel of the editor. Tree branches can be collapsed and expanded.

Illustration 2. Presentation of the data model structure

Selecting a tree node automatically filters the nodes in the list on the right side.

Illustration 3. Selecting a node in the data model editor

At the top of the node list the key that constitutes the current view filter is displayed: "client.surname" in this case.

Parameterization of model elements

Node

Illustration 3. Editing a model node

In the model node editing section you can edit the key and the documentation ("description") of the object. You can also mark the object as an array.

Next to the object's key there is a button that copies the key to the system clipboard.

The context menu contains an option to delete the node along with its descendants.

To add a field to a node click the "Add field".

Field

The field section in the data model also allows you to provide a default value for the field.

Illustration 4. Field in the model

Data source

Clicking on the data source chip or the pencil icon next to it opens a drawer with a list of data sources and the ability to edit usage (source order, source parameters, value mapping).

Illustration 5. Use of a data source

By default, for each leaf of the data model tree (i.e. a field that has no further sub-fields) the platform automatically adds a special data source of type ValueMap. This is a built-in source that stores the field value in the application's memory structure (in the so-called application value map) – it can be treated as the equivalent of a session variable storing data in the context of the whole application (form). The default ValueMap mapping uses the full path of keys of the given field as the key in this internal map (e.g. for the field country located inside the object personalData the key in the value map will be personalData.country). Thanks to this, after binding form fields to the model, no additional code is required to save the entered data – the value entered by the user will be automatically placed under the appropriate key in the model memory.