Component

Generate Angular Component

Create an Angular component following Momentum CMS conventions.

Arguments

• First argument: Library path (e.g., "admin", "ui", "admin/components")
• Second argument: Component name in kebab-case (e.g., "data-table", "field-renderer")

Steps

1. Create component files in libs/<library>/src/lib/<component>/:

   • <component>.ts (component class)
   • <component>.html (template, if complex)
   • <component>.spec.ts (tests)

2. Use this template for the component:

import { ChangeDetectionStrategy, Component, computed, input, output, signal, inject } from '@angular/core';

@Component({
  selector: 'mcms-<component-name>',
  host: { class: 'block' },
  template: `
    <!-- Template here -->
  `,
  changeDetection: ChangeDetectionStrategy.OnPush,
})
export class <PascalName>Component {
  // Signal inputs (use proper types, never `any`)
  readonly data = input.required<DataType>();

  // Optional inputs with defaults
  readonly disabled = input(false);

  // Signal outputs
  readonly valueChange = output<ValueType>();

  // Internal state
  private readonly _loading = signal(false);

  // Computed values
  readonly loading = this._loading.asReadonly();
  readonly hasData = computed(() => !!this.data());

  // Injected services
  private readonly http = inject(HttpClient);
}

3. Export from library's index.ts:

export { <PascalName>Component } from './lib/<component>/<component>';

Key Conventions

• NO standalone: true — default in Angular 21, redundant (ESLint enforced)
• NO any types — use proper interfaces (ESLint enforced)
• NO CommonModule import — unnecessary in Angular 21
• Always use ChangeDetectionStrategy.OnPush
• Use input() and input.required() for inputs
• Use output() for outputs
• Use signal() for internal state, computed() for derived values
• Use inject() for dependency injection
• Use @for/@if/@switch control flow
• Prefix selectors with mcms-

UI Component Patterns

No Wrapping Divs

Angular components create a host element. Style the host directly — do NOT add wrapper divs:

@Component({
  selector: 'mcms-button',
  host: { class: 'inline-flex items-center gap-2' },
  template: `<ng-content />`,
})

NOT:

// BAD: unnecessary wrapper div
template: `<div class="inline-flex items-center gap-2"><ng-content /></div>`,

Class Configuration

Accept a class input for Tailwind customization via hostClasses() computed:

@Component({
	selector: 'button[mcms-button]',
	host: { '[class]': 'hostClasses()' },
	template: `<ng-content />`,
	changeDetection: ChangeDetectionStrategy.OnPush,
})
export class McmsButtonComponent {
	readonly variant = input<'primary' | 'secondary'>('primary');
	readonly class = input('');

	readonly hostClasses = computed(
		() => `${baseClasses} ${variantClasses[this.variant()]} ${this.class()}`,
	);
}

Theme Service

Use McmsThemeService for dark mode support:

import { McmsThemeService } from '@momentumcms/admin';

@Component({...})
export class MyComponent {
  private readonly theme = inject(McmsThemeService);

  toggleDarkMode(): void {
    this.theme.toggleTheme();
  }

  readonly isDark = this.theme.isDark;           // computed signal
  readonly currentTheme = this.theme.theme;      // 'light' | 'dark' | 'system'
}

App Tailwind Setup

Apps using the admin library must:

1. tailwind.config.js — Use the admin preset and include library sources:

const adminPreset = require('../../libs/admin/tailwind.preset');

module.exports = {
	presets: [adminPreset],
	content: [
		join(__dirname, 'src/**/!(*.stories|*.spec).{ts,html}'),
		join(__dirname, '../../libs/admin/src/**/*.{ts,html}'),
		...createGlobPatternsForDependencies(__dirname),
	],
};

2. styles.css — Include CSS variables inline (Angular's esbuild can't resolve library CSS imports):

@tailwind base;
@tailwind components;
@tailwind utilities;

@layer base {
	:root {
		--mcms-background: 0 0% 100%;
		--mcms-foreground: 222 47% 11%;
		/* ... copy from libs/admin/src/styles/theme.css */
	}
	.dark {
		/* dark mode variables */
	}
}