MatMultiCheckboxField

Placeholder text displayed when the field is empty. Supports static strings, Observables, and Signals for dynamic content.

Note: placeholder lives at the field level, NOT inside props. The integration-layer props interfaces (InputProps, TextareaProps, SelectProps, DatepickerProps) intentionally omit placeholder — TypeScript's excess property check rejects props: { placeholder: ... } for any props literal typed against those interfaces.

Whether the field accepts null as a valid value.

When true, value may be null and an omitted value resolves to null (rather than the type-specific empty default). Orthogonal to required.

Read-side caveat: a user clearing a text input reads back as "", not null — this matches classic Reactive Forms and is enforced by the Web IDL contract. nullable is a contract for accepted values, not a guarantee of emitted ones.

Unique field identifier used for form binding and value tracking.

This key is used to associate the field with form values and must be unique within the form. It follows object property naming conventions.

Human-readable field label displayed to users.

Provides accessible labeling for form fields and is typically displayed above or beside the field input. Supports static strings, translation keys, Observables, and Signals for dynamic content.

Field-specific properties and configuration options.

Contains type-specific configuration that varies based on the field type. The shape is defined by the TProps generic parameter.

Native HTML attributes to pass through to the underlying element.

Contains attributes that are applied directly to the native input/element. Useful for accessibility, autocomplete hints, and custom attributes. The shape is defined by the TMeta generic parameter, which extends FieldMeta.

Additional CSS classes for custom styling.

Space-separated string of CSS class names that will be applied to the field container for custom styling.

Whether the field is disabled and cannot be interacted with.

When true, the field is rendered in a disabled state and cannot receive user input. The value can still be modified programmatically.

@value false

Whether the field is read-only.

When true, the field displays its value but cannot be modified by user interaction. Differs from disabled in styling and accessibility.

@value false

Whether the field is hidden from view.

When true, the field is not rendered in the UI. By default, validators on a hidden field are skipped — set {@link validateWhenHidden} to true (on the field, an ancestor, the form, or globally) to keep validation running while hidden. State logic and value derivations continue to apply.

@value false

Tab index for keyboard navigation.

Controls the order in which fields receive focus when navigating with the Tab key. Follows standard HTML tabindex behavior.

Whether to exclude this field's value from submission output when hidden.

Overrides both the global withValueExclusionDefaults() and form-level FormOptions settings.

Whether to exclude this field's value from submission output when disabled.

Overrides both the global withValueExclusionDefaults() and form-level FormOptions settings.

Whether to exclude this field's value from submission output when readonly.

Overrides both the global withValueExclusionDefaults() and form-level FormOptions settings.

Whether to run validation when this field is hidden — statically (hidden: true), via a hidden logic rule, or via any hidden ancestor.

When false, all validators on this field (built-in like required/email/min, custom validate()/expression validators, and required state logic) are skipped while the field is hidden. The hidden state, disabled state, readonly state, and value derivations continue to apply.

Inherited from the parent field — once a field overrides this value, all of its descendants inherit the new value unless they override in turn. Form-level FormOptions.validateWhenHidden is the root inherited value, falling back to the global default.

Column sizing configuration for responsive grid layout.

Specifies how many columns this field should span in a 12-column grid system. Supports responsive behavior and field arrangement.

Wrapper components to chain around this field.

- undefined — inherit auto-associations + form defaults. - null — render bare (see skipAuto/skipDefaults for partial opt-out). - readonly WrapperConfig[] — merged innermost with auto + defaults. - [] is not an opt-out; inherits like undefined.

Skip the auto-association layer (WrapperTypeDefinition.types) while keeping form-level defaults and any field-level wrappers. Use when a global wrapper auto-applies to this field type but isn't wanted here.

Skip the form-level defaultWrappers layer while keeping auto-associations and any field-level wrappers.

Addons rendered inside this field's slots (typically prefix / suffix).

Each addon declares its kind, slot, and kind-specific configuration. Whether a field type accepts addons — and which slots / kinds — is declared at registration via FieldTypeDefinition.addons. Field types without that registration ("Tier 3", e.g., toggle, radio) drop any addons value with a lenient warning at config init.

Shorthand for simple computed/derived fields.

The expression is evaluated whenever its dependencies change, and the result is set as this field's value.

Has access to formValue object containing all form values. Uses the same secure AST-based parser as other expressions.

For conditional derivations or derivations targeting other fields, use the full logic array with { type: 'derivation', ... }.