Cascade Select | Neural Native

Import

component.ts

import { NeuCascadeSelectComponent } from '@neural-ui/native/cascade-select';

Examples

Import ExampleComponent into its parent and place <app-example /> inside your application’s root neu-theme. The preview supplies the device frame and safe areas; use the root setup from Installation in your app.

A workspace, wherever you are

Move through region, country and office. Back revisits a level; selecting a leaf reveals its destination card.

View and copy the complete example

basic.component.ts

import { Component, signal, computed } from '@angular/core';
import { NeuCardComponent } from '@neural-ui/native/card';
import { NeuBadgeComponent } from '@neural-ui/native/badge';
import { NeuCascadeSelectComponent } from '@neural-ui/native/cascade-select';
import { View, Text, ScrollView } from '@ng-native/components';
import type { NeuTreeNode } from '@neural-ui/native';

@Component({
  selector: 'app-example',
  imports: [NeuCardComponent, NeuBadgeComponent, NeuCascadeSelectComponent, View, Text, ScrollView],
  template: `
    <scroll-view class="product-scroll" keyboardShouldPersistTaps="handled" [showsVerticalScrollIndicator]="true"><view class="product-stack"><view class="product-section"><text class="product-title" accessibilityRole="header">A workspace, wherever you are</text><text class="product-caption">Find your next office one level at a time</text></view>
    <view class="product-surface"><neu-cascade-select label="Office location" placeholder="Choose an office" rootLabel="Regions" [nodes]="locations" [(value)]="office" />
    <text class="product-caption">Region → Country → Office</text></view>
    @if (officeLabel()) { <neu-card [title]="officeLabel()" description="Your next team workspace" variant="outlined"><neu-badge label="Office selected" tone="success" /></neu-card> }</view></scroll-view>
  `,
  styles: `
.actions { gap: 12px; align-items: flex-start; } text { color: var(--neu-text, #172033); font-size: 16px; }

:host { flex: 1; flex-shrink: 1; min-height: 0; }
.product-scroll { flex: 1; flex-shrink: 1; height: 0px; min-height: 0; }
.product-stack { gap: 24px; padding-bottom: 20px; }
.product-section { gap: 12px; }
.product-row { flex-direction: row; align-items: center; gap: 12px; }
.product-copy { flex: 1; min-width: 0; gap: 4px; }
.product-title { color: var(--neu-text, #172033); font-size: 24px; line-height: 30px; font-weight: 600; }
.product-heading { color: var(--neu-text, #172033); font-size: 17px; line-height: 23px; font-weight: 600; }
.product-caption { color: var(--neu-muted, #596477); font-size: 14px; line-height: 20px; }
.product-actions { flex-direction: row; flex-wrap: wrap; align-items: center; gap: 8px; }
.product-surface { gap: 16px; padding: 16px; border-radius: 16px; background-color: var(--neu-surface, #ffffff); border-width: 1px; border-color: var(--neu-border, #a5afbf); }

  `,
})
export class ExampleComponent {
  readonly locations: readonly NeuTreeNode[] = [
    { id: 'europe', label: 'Europe', children: [
      { id: 'spain', label: 'Spain', children: [{ id: 'madrid', label: 'Madrid' }, { id: 'barcelona', label: 'Barcelona' }] },
      { id: 'france', label: 'France', children: [{ id: 'paris', label: 'Paris' }] },
    ] },
    { id: 'americas', label: 'North America', children: [
      { id: 'usa', label: 'United States', children: [{ id: 'austin', label: 'Austin' }, { id: 'new-york', label: 'New York' }] },
    ] },
  ];
  readonly office = signal('');
  readonly officeLabel = computed(() => this.locations.flatMap(region => region.children ?? []).flatMap(country => country.children ?? []).find(office => office.id === this.office())?.label || '');
}

Interactive playground

Change the settings and try the result.

Device captures shown in English.

Cascade Select · android · native capture — **Android**Native screenshot

Cascade Select · ios · native capture — **iOS**Native screenshot

API reference

Inputs

Name	Type	Default	Binding	Description
nodes	readonly NeuTreeNode[]	[]	Input	Hierarchical nodes with optional children. Keep IDs unique across the whole tree.
backLabel	string	'Back'	Input	Text or accessible name used for back. It does not perform the action by itself.
placeholder	string	'Choose item'	Input	Example or prompt displayed while the value is empty; keep a separate label.
closeLabel	string	'Dismiss options'	Input	Text or accessible name used for close. It does not perform the action by itself.
rootLabel	string	'All categories'	Input	Heading for the root level of the cascading category picker.
label	string	Required	Input	Human-readable name for the control, action or group.
disabled	boolean	false	Input	Disables user interaction. Values can still be supplied by the application.
readonly	boolean	false	Input	Prevents user editing or selection while retaining the current value.
invalid	boolean	false	Input	Marks the control invalid. Your form or application supplies the validation rule.
touched	boolean	false	Input	Field interaction state, supplied manually or through Signal Forms.
hint	string	''	Input	Field guidance shown when no error message is being displayed.
required	boolean	false	Input	Required-field presentation. Define the actual validation rule in your application form.
requiredLabel	string	'Required'	Input	Localized requirement announced with the field hint when required is true. Defaults to Required; it does not validate the value.
error	string	''	Input	Application-provided error message; combine it with the control’s invalid state.

Models

Name	Type	Default	Binding	Description
value	string	''	Model · two-way	Current edited value or selected ID(s), using the declared type. Bind a writable signal with [(value)].

Outputs

Name	Payload	When it emits
valueChange	string	Emits the updated value value. [(value)] binds this output together with its model input.
touch	void	Reports user interaction to the surrounding form or application.

Model state

Bind the signal with [(modelName)] without calling it. Use modelName() to read its value.

model-fields.ts

import { signal } from '@angular/core';

// Fields inside your component class
readonly value = signal<string>('');

Types and data interfaces

Use the imports in your application. The definitions below are provided for reference.

NeuOption

NeuOption.ts

import type { NeuOption } from '@neural-ui/native';

// Public definition for reference only. Import this type; do not redeclare it.
export interface NeuOption {
    readonly id: string;
    readonly label: string;
    readonly description?: string;
    readonly disabled?: boolean;
}

Field	Type	Requirement	Meaning
id	string	Required	Stable, unique identifier used for tracking and selection.
label	string	Required	Human-readable item name.
description	string	Optional	Optional supporting text; rendering depends on the control.
disabled	boolean	Optional	Prevents activating or selecting this item.

NeuTreeNode

NeuTreeNode.ts

import type { NeuTreeNode } from '@neural-ui/native';
import type { NeuOption } from '@neural-ui/native';

// Public definition for reference only. Import this type; do not redeclare it.
export interface NeuTreeNode extends NeuOption {
    readonly children?: readonly NeuTreeNode[];
}

Field	Type	Requirement	Meaning
children	readonly NeuTreeNode[]	Optional	Recursive child nodes; omit for a leaf.
id	string	Required	Stable, unique identifier used for tracking and selection.
label	string	Required	Human-readable item name.
description	string	Optional	Optional supporting text; rendering depends on the control.
disabled	boolean	Optional	Prevents activating or selecting this item.