Custom Fields

Overview

Custom fields allow you to add new data fields to both custom models and existing standard models. Each field has a data type, display widget, validation rules, and visibility conditions.

Custom fields are managed from App > Studio components > Fields.

The Fields list under Studio components shows only standalone custom fields (those not belonging to a custom model). Fields that belong to a custom model are managed directly from the Custom Model form or the View Builder.
Custom Fields grid view

Field Form

Custom Field form

The field form provides the following configuration options:

Basic Properties

Field Required Description

Name (1)

Yes

Technical name of the field. Must start with a letter and be unique within its model. The name is automatically normalized (special characters removed, camelCase formatting applied).

Title (2)

No

Display label shown to users. Supports translation.

Type (3)

Yes

Data type of the field. See Field Types below.

Default value (4)

No

Value pre-filled when creating a new record.

Help (5)

No

Tooltip text displayed when the user hovers over the field.

Sequence (6)

No

Order of the field in the form and grid views.

Studio App

  • Studio App: Associates the field with a Studio App for packaging.

This field is only visible when enableStudioApp is enabled in the configuration.

Field Types

Studio supports the following data types for custom fields:

Basic Field Types

Type Description Available Widgets

String

Single-line or multi-line text

Text (default), Email, URL, Password, HTML, CodeEditor

Integer

Whole numbers

Integer (default), Duration, Progress

Decimal

Decimal numbers with configurable precision

Decimal (default), Currency

Boolean

True/false checkbox

Boolean (default), Boolean-switch, InlineCheckbox

Date

Date without time

Date (default)

DateTime

Date with time

DateTime (default)

Time

Time without date

Time (default)

Relational Field Types

Type Description

Many-to-One (M2O)

Reference to a single record of another model. Requires a target model to be specified.

One-to-Many (O2M)

List of records from another model that reference this record. Requires a target model and a relationship field.

Many-to-Many (M2M)

Multiple references to records of another model. Creates a join table between the two models.

For relational fields, the following additional properties are available:

  • Target model: The model being referenced. When changed, the Form view and Grid view are automatically set to the default views for the target model.

  • Form view / Grid view: Specific views to use when displaying related records. The view selectors are filtered to only show views that match the selected target model.

  • Domain: A filtering expression to restrict selectable records

When you set the field type to String, the Visible in grid property is automatically set to true. For other types, you can manually enable it.

Selection Field Type

The Selection type creates a dropdown field backed by a selection list.

  • Selection: Reference to a MetaSelect or StudioSelection defining the available options

  • Widget: Choose between Select (default dropdown), NavSelect (horizontal tabs), RadioSelect (radio buttons), MultiSelect (multi-select), CheckboxSelect (checkboxes), or ImageSelect

Validation and Constraints

Min/Max Values

For Integer and Decimal fields, you can set minimum and maximum value constraints:

Property Description

Min size

Minimum allowed value. Records with values below this threshold will fail validation.

Max size

Maximum allowed value. Records with values above this threshold will fail validation.

Use min/max constraints to enforce business rules. For example, set min=0 on a quantity field to prevent negative values, or set max=100 on a percentage field.

Decimal Precision

For Decimal fields, configure the number format:

Property Description

Precision

Total number of significant digits (before and after the decimal point).

Scale

Number of digits after the decimal point.

For example, a field with precision=10 and scale=2 can store values like 12345678.90.

Required and Read-only

  • Required: When checked, the field must be filled before the record can be saved.

  • Read-only: When checked, the field is displayed but cannot be edited.

These can also be set dynamically using conditional expressions (requiredIf, readonlyIf).

Regex Validation

The Regex property allows you to define a regular expression pattern that the field value must match. This is useful for enforcing specific formats on String fields.

For example, use ^[A-Z]{2}[0-9]{4}$ to require a format like "AB1234".

Visibility and Conditions

Custom fields support conditional visibility and behavior through expressions:

Property Description Example

Show if

Field is visible only when the expression is true

$record.status == 'active'

Hide if

Field is hidden when the expression is true

$record.type == 'internal'

Required if

Field becomes required when the expression is true

$record.amount > 1000

Read-only if

Field becomes read-only when the expression is true

$record.status == 'validated'

See Conditional Expressions for the complete syntax reference.

Event Handlers

On Change

The onChange property specifies an action to execute when the field value changes. This can be used to:

  • Auto-fill other fields based on the current value

  • Trigger calculations

  • Show validation messages

On Click

The onClick property specifies an action to execute when the field is clicked. This is primarily used with Button fields.

Advanced Properties

Widget Attributes

The widgetAttrs property accepts a JSON object for configuring additional widget-specific attributes that are not exposed as standard form fields.

Example:

{"showBars": true, "max": 100}

Visibility in Grid

The Visible in grid checkbox controls whether the field appears as a column in grid (list) views. By default, new fields are visible in the grid.

Name Field

The Name field checkbox marks this field as the record’s display name. When a record of this custom model is referenced from another model (M2O), this field’s value is shown.

Context Fields

Context fields allow you to create conditional sub-forms where certain fields are only visible based on a parent field’s value:

  • Context field: The parent field whose value determines visibility

  • Context field target: The target model of the context field

  • Context field target name: The display field of the target model

  • Context field value: The specific value that triggers visibility

Include If

The includeIf property controls whether the field definition is included in the generated view XML at all. Unlike showIf (which hides the field with CSS), includeIf prevents the field from being rendered entirely.

Technical Details

Custom fields are stored in the MetaJsonField table. The Studio module extends this entity with additional fields:

Field Type Description

studioApp

M2O: StudioApp

Studio App grouping

metaSelect

M2O: MetaSelect

Linked selection definition

selectionText

Large String

Inline selection definition text

isSelectionField

Boolean

Whether this field uses a selection

uniqueModel

Computed

Computed unique model identifier

A unique constraint is enforced on the combination of name and uniqueModel (computed field), ensuring that field names are unique within a given model.

The MetaJsonField entity tracks over 30 fields for change auditing, including name, title, type, defaultValue, widget, help, all condition properties (showIf, hideIf, requiredIf, readonlyIf), and relational configuration (targetModel, gridView, formView).