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UI KIT development in Angular 18

Sep 13, 2024 pm 10:16 PM

Разработка UI KIT на Angular 18

Let's create several components of our application.

In this case, we need the following UI:

  • accordion - accordion;
  • autocomplete — input with autocomplete;
  • buttons - buttons;
  • cards - cards;
  • checkbox - checkboxes;
  • container - centers the content;
  • datepicker - date picker;
  • dialog - modal windows;
  • headline - promo text;
  • icons — set of svg icons;
  • input - inputs;
  • label - labels;
  • layout - layout;
  • nav - menu;
  • section — background task for sections in the content;
  • title - headings.

Complex elements will use angular/cdk (dialog, accordion) to simplify the process.

So let's add the package:

yarn add -D @angular/cdk
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And a little magic for scss:

{
  "inlineStyleLanguage": "scss",
  "stylePreprocessorOptions": {
    "includePaths": ["node_modules", "./"]
  }
}
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Creating utilities

Add a new utils directory to ui:

mkdir src/app/ui/utils
mkdir src/app/ui/utils/lib
echo >src/app/ui/utils/index.ts
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In tsconfig.json we will write the alias:

{
  "paths": {
    "@baf/ui/utils": ["src/app/ui/utils/index.ts"]
  }
}
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Let's define several types in types.ts:

export type ButtonMode = 'primary' | 'secondary' | 'tertiary' | undefined;

export type Size = 'small' | 'medium' | 'large' | undefined;
export type Align = 'left' | 'center' | 'right' | undefined;
export type ExtraSize = 'xsmall' | 'small' | 'medium' | 'large' | 'xlarge' | undefined;
export type Width = 'max' | 'initial' | undefined;
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They are all optional, so they contain undefined.

Some common properties of components:

  • align - centering left, right;
  • disabled - disabled state (relevant for forms);
  • size, extra-size - text size small, medium and large
  • mode - types of buttons;
  • width - element width.

AlignDirective

Example implementation of align:

import { Directive, inject, input } from '@angular/core';

import { ExtraClassService, toClass } from '@baf/core';

import type { Align } from './types';

@Directive({
  selector: '[bafAlign]',
  standalone: true,
  providers: [ExtraClassService],
})
export class AlignDirective {
  private readonly extraClassService = inject(ExtraClassService);

  readonly align = input<Align, Align>(undefined, {
    alias: 'bafAlign',
    transform: (value) => {
      this.extraClassService.update('align', toClass(value, 'align'));

      return value;
    },
  });
}
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ExtraClassService - a service that adds the corresponding class.

As an alternative, you can use @HostBinding('class.align-center') or set rules through the host.

Since angular does not allow you to include styles in the directive, let's add a mixin that needs to be imported for each component.

Create a file align.scss in src/stylesheets:

@mixin make-align() {
  &.align-left {
    text-align: left;
  }

  &.align-center {
    text-align: center;
  }

  &.align-right {
    text-align: right;
  }
}
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Usage example:

@use 'src/stylesheets/align' as align;
:host {
  @include align.make-align();
}
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The remaining directives are similar.

Container

Add a container and enter an alias.

mkdir src/app/ui/container
mkdir src/app/ui/container/lib
echo >src/app/ui/container/index.ts
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Generate the component:

yarn ng g c container
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Move it to src/app/ui/container/lib and edit ContainerComponent:

import { ChangeDetectionStrategy, Component } from '@angular/core';
import { RouterOutlet } from '@angular/router';

import { AlignDirective } from '@baf/ui/utils';

import { FluidDirective } from './fluid.directive';
import { MobileDirective } from './mobile.directive';

@Component({
  selector: 'baf-container',
  standalone: true,
  imports: [RouterOutlet],
  template: '<ng-content/>',
  styleUrl: './container.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
  host: {
    class: 'baf-container',
  },
  hostDirectives: [
    {
      directive: FluidDirective,
      inputs: ['bafFluid'],
    },
    {
      directive: MobileDirective,
      inputs: ['bafMobile'],
    },
    {
      directive: AlignDirective,
      inputs: ['bafAlign'],
    },
  ],
})
export class ContainerComponent {}
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Add styles:

@use 'src/stylesheets/align' as align;
@use 'src/stylesheets/device' as device;

:host {
  display: flex;
  flex-direction: column;
  margin-left: auto;
  margin-right: auto;
  width: 100%;

  &.fluid {
    max-width: 100%;
  }

  &:not(.mobile-no-gutter) {
    padding-left: 1rem;
    padding-right: 1rem;
  }

  @include align.make-align();

  @include device.media-tablet-portrait() {
    &:not(.fluid) {
      max-width: 788px;
    }
  }

  @include device.media-tablet-landscape() {
    &:not(.fluid) {
      max-width: 928px;
    }
  }

  @include device.media-web-portrait() {
    &:not(.fluid) {
      max-width: 808px;
    }
  }

  @include device.media-web-landscape() {
    &:not(.fluid) {
      max-width: 1200px;
    }
  }
}
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Width mixins taken from material:

@mixin media-handset() {
  @media (max-width: 599.98px) and (orientation: portrait), (max-width: 959.98px) and (orientation: landscape) {
    @content;
  }
}
@mixin media-handset-up() {
  @media (min-width: 0) and (orientation: portrait), (min-width: 0) and (orientation: landscape) {
    @content;
  }
}

@mixin media-handset-portrait() {
  @media (max-width: 599.98px) and (orientation: portrait) {
    @content;
  }
}

@mixin media-handset-landscape() {
  @media (max-width: 959.98px) and (orientation: landscape) {
    @content;
  }
}

@mixin media-tablet() {
  @media (min-width: 600px) and (max-width: 839.98px) and (orientation: portrait),
    (min-width: 960px) and (max-width: 1279.98px) and (orientation: landscape) {
    @content;
  }
}

@mixin media-tablet-up() {
  @media (min-width: 600px) and (orientation: portrait), (min-width: 960px) and (orientation: landscape) {
    @content;
  }
}

@mixin media-tablet-landscape() {
  @media (min-width: 960px) and (max-width: 1279.98px) and (orientation: landscape) {
    @content;
  }
}

@mixin media-tablet-portrait() {
  @media (min-width: 600px) and (max-width: 839.98px) and (orientation: portrait) {
    @content;
  }
}

@mixin media-web() {
  @media (min-width: 840px) and (orientation: portrait), (min-width: 1280px) and (orientation: landscape) {
    @content;
  }
}

@mixin media-web-up() {
  @media (min-width: 840px) and (orientation: portrait), (min-width: 1280px) and (orientation: landscape) {
    @content;
  }
}

@mixin media-web-portrait() {
  @media (min-width: 840px) and (orientation: portrait) {
    @content;
  }
}

@mixin media-web-landscape() {
  @media (min-width: 1280px) and (orientation: landscape) {
    @content;
  }
}
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We will also create two directives FluidDirective and MobileDirective:

import { coerceBooleanProperty } from '@angular/cdk/coercion';
import { Directive, inject, input } from '@angular/core';

import type { CoerceBoolean } from '@baf/core';
import { ExtraClassService } from '@baf/core';

@Directive({
  selector: 'baf-container[bafFluid]',
  standalone: true,
  providers: [ExtraClassService],
})
export class FluidDirective {
  private readonly extraClassService = inject(ExtraClassService);

  readonly fluid = input<CoerceBoolean, CoerceBoolean>(undefined, {
    alias: 'bafFluid',
    transform: (value) => {
      this.extraClassService.patch('fluid', coerceBooleanProperty(value));

      return value;
    },
  });
}
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import { coerceBooleanProperty } from '@angular/cdk/coercion';
import { Directive, inject, input } from '@angular/core';

import type { CoerceBoolean } from '@baf/core';
import { ExtraClassService } from '@baf/core';

@Directive({
  selector: 'baf-container[bafMobile]',
  standalone: true,
  providers: [ExtraClassService],
})
export class MobileDirective {
  private readonly extraClassService = inject(ExtraClassService);

  readonly mobile = input<CoerceBoolean, CoerceBoolean>(undefined, {
    alias: 'bafMobile',
    transform: (value) => {
      this.extraClassService.patch('mobile-no-gutter', coerceBooleanProperty(value));

      return value;
    },
  });
}
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Title, Label, Headline, Section and Card

Add a title and enter an alias:

mkdir src/app/ui/title
mkdir src/app/ui/title/lib
echo >src/app/ui/title/index.ts
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Generate the component:

yarn ng g c title
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Move it to src/app/ui/title/lib and edit TitleComponent:

import { ChangeDetectionStrategy, Component } from '@angular/core';

import { AlignDirective, SizeDirective } from '@baf/ui/utils';

@Component({
  selector: 'baf-title,[baf-title],[bafTitle]',
  standalone: true,
  template: '<ng-content/>',
  styleUrl: './title.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
  host: {
    class: 'baf-title',
  },
  hostDirectives: [
    {
      directive: SizeDirective,
      inputs: ['bafSize'],
    },
    {
      directive: AlignDirective,
      inputs: ['bafAlign'],
    },
  ],
})
export class TitleComponent {}
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A few styles:

@use 'src/stylesheets/align' as align;
@use 'src/stylesheets/size' as size;
@use 'src/stylesheets/typography' as typography;

:host {
  @include size.make-size() using ($size) {
    @if $size == small {
      @include typography.title-small();
    } @else if $size == medium {
      @include typography.title-medium();
    } @else if $size == large {
      @include typography.title-large();
    }
  }
  @include align.make-align();
}
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We do the rest in the same way.

Buttons

Let's move on to creating more complex widgets.

Add buttons and enter an alias:

mkdir src/app/ui/buttons
mkdir src/app/ui/buttons/lib
echo >src/app/ui/buttons/index.ts
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Since buttons are needed in several types, we will set the basic types -ButtonBase and AnchorBase:

import type { FocusOrigin } from '@angular/cdk/a11y';
import { FocusMonitor } from '@angular/cdk/a11y';
import { coerceBooleanProperty } from '@angular/cdk/coercion';
import type { AfterViewInit, OnDestroy, OnInit } from '@angular/core';
import { Directive, ElementRef, inject, NgZone } from '@angular/core';

@Directive()
export class ButtonBase implements AfterViewInit, OnDestroy {
  protected readonly elementRef = inject(ElementRef);

  private isDisabled = false;

  private readonly focusMonitor = inject(FocusMonitor);

  get disabled(): boolean {
    return this.isDisabled;
  }

  set disabled(value: string | boolean | null | undefined) {
    const disabled = coerceBooleanProperty(value);
    if (disabled !== this.isDisabled) {
      this.isDisabled = disabled;
    }
  }

  ngAfterViewInit() {
    this.focusMonitor.monitor(this.elementRef, true);
  }

  ngOnDestroy() {
    this.focusMonitor.stopMonitoring(this.elementRef);
  }

  focus(origin: FocusOrigin = 'program', options?: FocusOptions): void {
    if (origin) {
      this.focusMonitor.focusVia(this.elementRef.nativeElement, origin, options);
    } else {
      this.elementRef.nativeElement.focus(options);
    }
  }
}

@Directive()
export class AnchorBase extends ButtonBase implements OnInit, OnDestroy {
  private readonly ngZone = inject(NgZone);

  protected readonly haltDisabledEvents = (event: Event) => {
    if (this.disabled) {
      event.preventDefault();
      event.stopImmediatePropagation();
    }
  };

  ngOnInit(): void {
    this.ngZone.runOutsideAngular(() => {
      this.elementRef.nativeElement.addEventListener('click', this.haltDisabledEvents);
    });
  }

  override ngOnDestroy(): void {
    super.ngOnDestroy();
    this.elementRef.nativeElement.removeEventListener('click', this.haltDisabledEvents);
  }
}
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Implementation taken from Angular Material 2.

I haven’t looked at Material 3 in Angular and I don’t think it’s worth it. The complexity of the components is slightly greater than infinity.

As you can see from the example, the disabled state is defined, as well as focus observers.

Let's create a simple button. In our case, this is a wrapper over the standard one.

Template - .

import { ChangeDetectionStrategy, Component } from '@angular/core';

import { DisabledDirective, ExtraSizeDirective, ModeDirective, WidthDirective } from '@baf/ui/utils';

import { AnchorBase, ButtonBase } from '../base/button-base';

@Component({
  // eslint-disable-next-line @angular-eslint/component-selector
  selector: 'button[baf-button]',
  standalone: true,
  template: '<ng-content />',
  styleUrl: './button.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
  host: {
    class: 'baf-button',
  },
  hostDirectives: [
    {
      directive: ModeDirective,
      inputs: ['bafMode'],
    },
    {
      directive: ExtraSizeDirective,
      inputs: ['bafSize'],
    },
    {
      directive: DisabledDirective,
      inputs: ['disabled'],
    },
    {
      directive: WidthDirective,
      inputs: ['bafWidth'],
    },
  ],
})
export class ButtonComponent extends ButtonBase {}

@Component({
  // eslint-disable-next-line @angular-eslint/component-selector
  selector: 'a[baf-button]',
  standalone: true,
  template: '<ng-content />',
  styleUrls: ['./button.component.scss'],
  changeDetection: ChangeDetectionStrategy.OnPush,
  host: {
    class: 'baf-button',
  },
  hostDirectives: [
    {
      directive: ModeDirective,
      inputs: ['bafMode'],
    },
    {
      directive: ExtraSizeDirective,
      inputs: ['bafSize'],
    },
    {
      directive: DisabledDirective,
      inputs: ['disabled'],
    },
    {
      directive: WidthDirective,
      inputs: ['bafWidth'],
    },
  ],
})
export class AnchorComponent extends AnchorBase {}
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В компоненте определены общие директивы, в которые и вынесена вся логика.

Немного SCSS:

@use 'src/stylesheets/button' as button;
@use 'src/stylesheets/width' as width;

:host {
  display: inline-flex;
  flex-direction: row;
  align-items: center;
  justify-content: center;
  padding: 0.5rem 1.5rem;

  border: none;
  box-shadow: none;
  border-radius: 3px;
  cursor: pointer;
  text-decoration: none;

  &.mode-primary {
    @include button.mode(--md-sys-color-primary-container, --md-sys-color-on-primary, --md-sys-color-primary);
  }

  &.mode-secondary {
    @include button.mode(--md-sys-color-secondary-container, --md-sys-color-on-secondary, --md-sys-color-secondary);
  }

  &.mode-tertiary {
    @include button.mode(--md-sys-color-tertiary-container, --md-sys-color-on-tertiary, --md-sys-color-tertiary);
  }

  @include button.disabled();
  @include button.sizes();
  @include width.make-width();
}
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Теперь создадим icon-button.

Макет:

<span class="icon-content">
  <ng-content />
</span>
<span class="state-layer"></span>
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import { ChangeDetectionStrategy, Component } from '@angular/core';

import { DisabledDirective, ExtraSizeDirective, ModeDirective } from '@baf/ui/utils';

import { AnchorBase, ButtonBase } from '../base/button-base';

@Component({
  // eslint-disable-next-line @angular-eslint/component-selector
  selector: 'button[baf-icon-button]',
  standalone: true,
  templateUrl: './icon-button.component.html',
  styleUrl: './icon-button.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
  host: {
    class: 'baf-icon-button',
  },
  hostDirectives: [
    {
      directive: ModeDirective,
      inputs: ['bafMode'],
    },
    {
      directive: ExtraSizeDirective,
      inputs: ['bafSize'],
    },
    {
      directive: DisabledDirective,
      inputs: ['disabled'],
    },
  ],
})
export class IconButtonComponent extends ButtonBase {}

@Component({
  // eslint-disable-next-line @angular-eslint/component-selector
  selector: 'a[baf-icon-button]',
  standalone: true,
  templateUrl: './icon-button.component.html',
  styleUrl: './icon-button.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
  host: {
    class: 'baf-icon-button',
  },
  hostDirectives: [
    {
      directive: ModeDirective,
      inputs: ['bafMode'],
    },
    {
      directive: ExtraSizeDirective,
      inputs: ['bafSize'],
    },
    {
      directive: DisabledDirective,
      inputs: ['disabled'],
    },
  ],
})
export class IconAnchorComponent extends AnchorBase {}
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Стилизуем кнопки:

:host {
  display: inline-flex;
  flex-direction: row;
  flex-wrap: nowrap;
  align-items: center;
  justify-content: center;

  height: 48px;
  width: 48px;
  padding: 4px;
  border: none;
  z-index: 0;
  gap: 8px;
  white-space: nowrap;
  user-select: none;
  background-color: transparent;
  text-decoration: none;

  cursor: pointer;

  border-radius: var(--md-sys-shape-corner-full);

  position: relative;
}

.state-layer {
  position: absolute;
  width: 100%;
  height: 100%;
  left: 0;
  top: 0;
  right: 0;
  bottom: 0;
  display: block;
  z-index: 1;
  opacity: 0;
  border-radius: inherit;
}

.icon-content {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--md-sys-color-on-surface-variant);
  fill: var(--md-sys-color-on-surface-variant);
  line-height: 1;

  :host:hover & {
    color: var(--md-sys-color-on-surface);
    fill: var(--md-sys-color-on-surface);
  }
}
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Icons

Добавим компонент для иконок.

mkdir src/app/ui/icons
mkdir src/app/ui/icons/lib
echo >src/app/ui/icons/index.ts
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Запускаем команду:

yarn ng g c icon
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Переносим его в src/app/ui/title/lib и отредактируем IconComponent:

import { ChangeDetectionStrategy, Component } from '@angular/core';

@Component({
  // eslint-disable-next-line @angular-eslint/component-selector
  selector: 'svg[baf-icon]',
  standalone: true,
  imports: [],
  templateUrl: './icon.component.html',
  styleUrl: './icon.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
})
export class IconComponent {}
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Стили:

src/app/ui/icons/lib/icon/icon.component.scss
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Пример использования на иконке домой:

<svg baf-icon xmlns="http://www.w3.org/2000/svg" height="24px" viewBox="0 -960 960 960" width="24px">
  <path d="M240-200h120v-240h240v240h120v-360L480-740 240-560v360Zm-80 80v-480l320-240 320 240v480H520v-240h-80v240H160Zm320-350Z" />
</svg>
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import { ChangeDetectionStrategy, Component } from '@angular/core';

import { IconComponent } from '../icon/icon.component';

@Component({
  selector: 'baf-icon-home',
  standalone: true,
  imports: [IconComponent],
  templateUrl: './home.component.html',
  styleUrl: './home.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
})
export class HomeComponent {}
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Так же созданы все остальные иконки:

  • arrow-down - стрелка вниз;
  • arrow-up - стрелка вверх;
  • chevron-left - стрелка влево;
  • chevron-right - стрелка вправо;
  • home - дом;
  • logo - лого;
  • star - звезда;
  • sync-alt - рефреш.

Accordion

Реализуем аккордеон:

mkdir src/app/ui/accordion
mkdir src/app/ui/accordion/lib
echo >src/app/ui/accordion/index.ts
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Запускаем команду:

yarn ng g c accordion
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Добавим интерфейс:

export interface AccordionItem {
  readonly title: string;
  readonly description: string;
}
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В компоненте будем выводить список элементов:

import { CdkAccordionModule } from '@angular/cdk/accordion';
import { ChangeDetectionStrategy, Component, input } from '@angular/core';

import { ArrowDownComponent, ArrowUpComponent } from '@baf/ui/icons';

export interface AccordionItem {
  readonly title: string;
  readonly description: string;
}

@Component({
  selector: 'baf-accordion',
  standalone: true,
  imports: [CdkAccordionModule, ArrowDownComponent, ArrowUpComponent],
  templateUrl: './accordion.component.html',
  styleUrl: './accordion.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
})
export class AccordionComponent {
  readonly items = input.required<AccordionItem[]>();
}
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Шаблон:

<cdk-accordion>
  @for (item of items(); track item.title; let index = $index) {
    <cdk-accordion-item
      class="accordion"
      #accordionItem="cdkAccordionItem"
      role="button"
      tabindex="0"
      [attr.id]="'accordion-header-' + index"
      [attr.aria-expanded]="accordionItem.expanded"
      [attr.aria-controls]="'accordion-body-' + index"
    >
      <div class="accordion-header" (click)="accordionItem.toggle()">
        @if (accordionItem.expanded) {
          <baf-arrow-down />
        } @else {
          <baf-arrow-up />
        }
        <span> {{ item.title }} </span>
      </div>
      <div
        class="accordion-body"
        role="region"
        [style.display]="accordionItem.expanded ? '' : 'none'"
        [attr.id]="'accordion-body-' + index"
        [attr.aria-labelledby]="'accordion-header-' + index"
      >
        {{ item.description }}
      </div>
    </cdk-accordion-item>
  }
</cdk-accordion>
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Стили:

.accordion {
  display: block;

  &:not(:last-child) {
    border-bottom: 1px solid var(--md-sys-color-surface-variant);
    padding-bottom: 1rem;
    margin-bottom: 1rem;
  }
}

.accordion-header {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  line-height: 1;
  user-select: none;
}

.accordion-body {
  padding: 1rem 1rem 0 2rem;
}
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Checkbox

Создадим чекбокс.

Отмечу, что оформление я взял из проекта мериалайз

mkdir src/app/ui/checkbox
mkdir src/app/ui/checkbox/lib
echo >src/app/ui/checkbox/index.ts
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Запускаем команду:

yarn ng g c checkbox
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Разметка:

<label>
  <input type="checkbox" [name]="options().name ?? ''" [formControl]="control()" />
  <span><ng-content /></span>
</label>
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Украду немного стилей из Material CSS:

[type='checkbox']:not(:checked),
[type='checkbox']:checked {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

[type='checkbox']:checked {
  + span:before {
    top: -4px;
    left: -5px;
    width: 12px;
    height: 22px;
    border-top: 2px solid transparent;
    border-left: 2px solid transparent;
    border-right: 2px solid var(--md-sys-color-primary);
    border-bottom: 2px solid var(--md-sys-color-primary);
    transform: rotate(40deg);
    backface-visibility: hidden;
    transform-origin: 100% 100%;
  }

  &:disabled + span:before {
    border-right: 2px solid var(--md-sys-color-shadow);
    border-bottom: 2px solid var(--md-sys-color-shadow);
  }
}

[type='checkbox'] {
  + span {
    position: relative;
    padding-left: 35px;
    cursor: pointer;
    display: inline-block;
    height: 25px;
    line-height: 25px;
    font-size: 1rem;
    user-select: none;
  }

  &:not(:checked):disabled + span:before {
    border: none;
    background-color: var(--md-sys-color-shadow);
  }

  // General
  + span:after {
    border-radius: 2px;
  }

  + span:before,
  + span:after {
    content: '';
    left: 0;
    position: absolute;
    /* .1s delay is for check animation */
    transition:
      border 0.25s,
      background-color 0.25s,
      width 0.2s 0.1s,
      height 0.2s 0.1s,
      top 0.2s 0.1s,
      left 0.2s 0.1s;
    z-index: 1;
  }

  // Unchecked style
  &:not(:checked) + span:before {
    width: 0;
    height: 0;
    border: 3px solid transparent;
    left: 6px;
    top: 10px;
    transform: rotateZ(37deg);
    transform-origin: 100% 100%;
  }

  &:not(:checked) + span:after {
    height: 20px;
    width: 20px;
    background-color: transparent;
    border: 2px solid var(--md-sys-color-outline);
    top: 0;
    z-index: 0;
  }

  // Checked style
  &:checked {
    + span:before {
      top: 0;
      left: 1px;
      width: 8px;
      height: 13px;
      border-top: 2px solid transparent;
      border-left: 2px solid transparent;
      border-right: 2px solid var(--md-sys-color-on-primary);
      border-bottom: 2px solid var(--md-sys-color-on-primary);
      transform: rotateZ(37deg);
      transform-origin: 100% 100%;
    }

    + span:after {
      top: 0;
      width: 20px;
      height: 20px;
      border: 2px solid var(--md-sys-color-primary);
      background-color: var(--md-sys-color-primary);
      z-index: 0;
    }
  }

  // Disabled style
  &:disabled:not(:checked) + span:before {
    background-color: transparent;
    border: 2px solid transparent;
  }

  &:disabled:not(:checked) + span:after {
    border-color: transparent;
    background-color: var(--md-sys-color-outline);
  }

  &:disabled:checked + span:before {
    background-color: transparent;
  }

  &:disabled:checked + span:after {
    background-color: var(--md-sys-color-outline);
    border-color: var(--md-sys-color-outline);
  }
}
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Сам компонент:

import { ChangeDetectionStrategy, Component, input } from '@angular/core';
import type { FormControl } from '@angular/forms';
import { ReactiveFormsModule } from '@angular/forms';

export interface CheckboxOptions {
  readonly [key: string]: unknown;

  readonly name?: string;
}

@Component({
  selector: 'baf-checkbox',
  standalone: true,
  imports: [ReactiveFormsModule],
  templateUrl: './checkbox.component.html',
  styleUrl: './checkbox.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
})
export class CheckboxComponent {
  readonly control = input.required<FormControl<boolean>>();
  readonly options = input<CheckboxOptions>({});
}
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Input

Реализуем инпут:

mkdir src/app/ui/input
mkdir src/app/ui/input/lib
echo >src/app/ui/input/index.ts
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Выполним инструкцию:

yarn ng g c input
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InputComponent будет оберткой над input.

import { ChangeDetectionStrategy, Component, ElementRef, inject } from '@angular/core';
import { NgControl } from '@angular/forms';

@Component({
  // eslint-disable-next-line @angular-eslint/component-selector
  selector: 'input[baf-input]',
  standalone: true,
  imports: [],
  template: '<ng-content/>',
  styleUrl: './input.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
  host: {
    class: 'baf-input',
  },
})
export class InputComponent {
  readonly elementRef: ElementRef<HTMLInputElement> = inject(ElementRef);
  readonly ngControl = inject(NgControl);
}
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Добавим SCSS:

:host {
  display: block;
  background-color: transparent;
  height: 100%;
  width: 100%;
  padding: 0;
  border: none;
  outline: none;

  &:hover,
  &:focus,
  &:active {
    outline: none;
  }

  &::placeholder {
    color: var(--md-sys-color-on-surface-variant);
  }

  :host-context(.is-invalid) {
    color: var(--md-sys-color-error);
  }
}
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Перенесем концепты из mat-form-field:

yarn ng g c input-control
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Разметка и стили:

<div class="input-container">
  <ng-content select="[baf-input-prefix]" />
  <div class="input-box">
    <ng-content select="label[baf-label],baf-label" />
    <div class="input">
      <ng-content select="input[baf-input],baf-input" />
    </div>
  </div>
  <ng-content select="[baf-input-suffix]" />
</div>
<ng-content />
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:host {
  display: flex;
  flex-direction: column;
  position: relative;
  width: 100%;

  &.is-disabled {
    cursor: not-allowed;
    pointer-events: none;
    color: rgba(var(--md-sys-color-on-surface-rgba), 0.38);

    .input {
      color: rgba(var(--md-sys-color-on-surface-rgba), 0.38);
    }
  }

  &.is-pressed,
  &.is-value {
    .input {
      opacity: 1;
    }
  }
}

.input-box {
  position: relative;
  margin: 0 16px;
  justify-content: center;
  height: 100%;
  flex-grow: 1;
}

.input-container {
  display: flex;
  flex-direction: row;
  flex-wrap: nowrap;
  align-items: center;
  background-color: var(--md-sys-color-surface-variant);
  color: var(--md-sys-color-on-surface-variant);
  border-radius: var(--md-sys-shape-corner-extra-small-top);
  height: 3rem;
}

.input {
  opacity: 0;
  height: 100%;
  width: 100%;
  position: relative;
  z-index: 2;
  transition: opacity 0.1s;
  padding: 12px 0 0 0;
}
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Возможно можно и разбить на несколько дочерних компонентов, но и так получается достаточно сложно.

Используемые вспомогательные директивы для префиксов и прочего.

src/app/ui/input/lib/input-display.directive.ts:

import { Directive, ElementRef, forwardRef, inject, input } from '@angular/core';
import type { ControlValueAccessor } from '@angular/forms';
import { NG_VALUE_ACCESSOR } from '@angular/forms';

import type { ChangeFn, DisplayFn, TouchedFn } from '@baf/core';

@Directive({
  selector: 'input[formControlName][bafInputDisplay],input[formControl][bafInputDisplay]',
  standalone: true,
  providers: [
    {
      provide: NG_VALUE_ACCESSOR,
      useExisting: forwardRef(() => InputDisplayDirective),
      multi: true,
    },
  ],
  host: {
    '(blur)': 'onTouched()',
    '(input)': 'onInput($event)',
  },
})
export class InputDisplayDirective implements ControlValueAccessor {
  private readonly elementRef = inject(ElementRef<HTMLInputElement>);
  readonly display = input.required<DisplayFn>({ alias: 'bafInputDisplay' });

  onChange!: ChangeFn;
  onTouched!: TouchedFn;

  registerOnChange(fn: ChangeFn): void {
    this.onChange = fn;
  }

  registerOnTouched(fn: TouchedFn): void {
    this.onTouched = fn;
  }

  writeValue(value: unknown): void {
    this.elementRef.nativeElement.value = this.display()(value);
  }

  onInput(event: Event): void {
    const { value } = event.target as HTMLInputElement;
    this.elementRef.nativeElement.value = this.display()(value);
    this.onChange(value);
  }
}
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src/app/ui/input/lib/input-mask.directive.ts:

import type { OnInit } from '@angular/core';
import { Directive, ElementRef, forwardRef, inject, InjectionToken, input } from '@angular/core';
import type { ControlValueAccessor } from '@angular/forms';
import { NG_VALUE_ACCESSOR } from '@angular/forms';

import type { ChangeFn, MaskFn, TouchedFn } from '@baf/core';

export const INPUT_MASK_VALUES = new InjectionToken<Record<string, RegExp>>('INPUT_MASK_VALUES');

const DEFAULT_INPUT_MASK_VALUES: Record<string, RegExp> = { 0: /[0-9]/, a: /[a-z]/, A: /[A-Z]/, B: /[a-zA-Z]/ };

export const DEFAULT_MASK_FN: MaskFn = (value) => value;

@Directive({
  selector: 'input[formControlName][bafInputMask],input[formControl][bafInputMask]',
  standalone: true,
  providers: [
    {
      provide: NG_VALUE_ACCESSOR,
      useExisting: forwardRef(() => InputMaskDirective),
      multi: true,
    },
  ],
  host: {
    '(blur)': 'onTouched()',
    '(input)': 'onInput($event)',
  },
})
export class InputMaskDirective implements ControlValueAccessor, OnInit {
  private readonly maskValues = inject(INPUT_MASK_VALUES, { optional: true }) ?? DEFAULT_INPUT_MASK_VALUES;
  private readonly elementRef = inject(ElementRef<HTMLInputElement>);

  private lastValue?: string;

  private readonly maskFormats = `(${Object.keys(this.maskValues)
    .map((key) => {
      const regexStr = this.maskValues[key].toString();

      return regexStr.substring(1, regexStr.length - 1);
    })
    .join('|')})`;

  readonly mask = input.required<string>({ alias: 'bafInputMask' });
  readonly maskFrom = input<MaskFn>(DEFAULT_MASK_FN, { alias: 'bafInputMaskFrom' });
  readonly maskTo = input<MaskFn>(DEFAULT_MASK_FN, { alias: 'bafInputMaskTo' });

  onChange!: ChangeFn;
  onTouched!: TouchedFn;

  registerOnChange(fn: ChangeFn): void {
    this.onChange = fn;
  }

  registerOnTouched(fn: TouchedFn): void {
    this.onTouched = fn;
  }

  writeValue(value: string | undefined | null): void {
    this.elementRef.nativeElement.value = this.getMaskedValue(this.maskTo()(value));
  }

  onInput(event: Event): void {
    const { value } = event.target as HTMLInputElement;
    const masked = this.getMaskedValue(value);
    this.elementRef.nativeElement.value = masked;
    this.onChange(this.maskFrom()(masked));
  }

  ngOnInit(): void {
    if (!this.mask()) {
      console.warn(`Property mask should not be empty for input:`, this.elementRef.nativeElement);
    }
  }

  getMaskedValue(value: string | undefined | null): string | undefined | null {
    if (!this.mask() || !value || value === this.lastValue) {
      return value;
    }

    const masked = this.valueToFormat(value, this.mask(), this.lastValue ? this.lastValue.length > value.length : false, this.lastValue);
    this.lastValue = masked;

    return masked;
  }

  /**
   * @see https://gist.github.com/rami-alloush/3ee792fd0647b73de5f863a2719c78c6
   */
  private valueToFormat(value: string, format: string, goingBack?: boolean, prevValue?: string): string {
    let maskedValue = '';
    const unmaskedValue = value.replace(' ', '').match(new RegExp(this.maskFormats, 'g'))?.join('') ?? '';

    const formats = new RegExp(this.maskFormats);
    const isLastCharFormatter = !formats.test(value[value.length - 1]);
    const isPrevLastCharFormatter = prevValue && !formats.test(prevValue[prevValue.length - 1]);

    let formatOffset = 0;
    for (let index = 0, max = Math.min(unmaskedValue.length, format.length); index < max; ++index) {
      const valueChar = unmaskedValue[index];
      let formatChar = format[formatOffset + index];
      let formatRegex = this.maskValues[formatChar];

      if (formatChar && !formatRegex) {
        maskedValue += formatChar;
        formatChar = format[++formatOffset + index];
        formatRegex = this.maskValues[formatChar];
      }

      if (valueChar && formatRegex) {
        if (formatRegex && formatRegex.test(valueChar)) {
          maskedValue += valueChar;
        } else {
          break;
        }
      }

      const nextFormatChar = format[formatOffset + index + 1];
      const nextFormatRegex = this.maskValues[nextFormatChar];
      const isLastIteration = index === max - 1;

      if (isLastIteration && nextFormatChar && !nextFormatRegex) {
        if (!isLastCharFormatter && goingBack) {
          if (prevValue && !isPrevLastCharFormatter) {
            continue;
          }
          maskedValue = maskedValue.substring(0, formatOffset + index);
        } else {
          maskedValue += nextFormatChar;
        }
      }
    }

    return maskedValue;
  }
}
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src/app/ui/input/lib/input-prefix.directive.ts:

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

@Directive({
  selector: '[bafInputPrefix]',
  standalone: true,
  host: {
    class: 'input-prefix',
    '[style.margin-left]': '"12px"',
  },
})
export class InputPrefixDirective {}
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src/app/ui/input/lib/input-suffix.directive.ts:

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

@Directive({
  selector: '[bafInputSuffix]',
  standalone: true,
  host: {
    class: 'baf-input-suffix',
    '[style.margin-right]': '"12px"',
  },
})
export class InputSuffixDirective {}
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Логика работы достаточно проста:

import type { AfterViewInit, OnDestroy } from '@angular/core';
import { ChangeDetectionStrategy, Component, contentChild, DestroyRef, ElementRef, inject, Renderer2 } from '@angular/core';
import { takeUntilDestroyed } from '@angular/core/rxjs-interop';
import type { FormControlStatus } from '@angular/forms';
import { TouchedChangeEvent } from '@angular/forms';
import { filter, startWith, tap } from 'rxjs';

import { LabelComponent } from '@baf/ui/label';

import { InputComponent } from './input.component';

@Component({
  selector: 'baf-input-control',
  templateUrl: './input-control.component.html',
  styleUrls: ['./input-control.component.scss'],
  changeDetection: ChangeDetectionStrategy.OnPush,
  standalone: true,
  host: {
    class: 'baf-input-control',
  },
})
export class InputControlComponent implements AfterViewInit, OnDestroy {
  readonly destroyRef = inject(DestroyRef);
  readonly elementRef: ElementRef<HTMLInputElement> = inject(ElementRef);
  readonly renderer = inject(Renderer2);

  readonly label = contentChild<LabelComponent>(LabelComponent);
  readonly input = contentChild.required<InputComponent>(InputComponent);

  private isDisabled = false;

  ngAfterViewInit(): void {
    const input = this.input();
    if (!input) {
      console.warn('Input[baf-input] not found. Add child <input baf-input /> in <baf-input-control></baf-input-control>');
      return;
    }

    input.elementRef.nativeElement.addEventListener('click', this.onFocusin);
    input.elementRef.nativeElement.addEventListener('focusout', this.onFocusout);
    input.elementRef.nativeElement.addEventListener('input', this.onInput);
    input.elementRef.nativeElement.addEventListener('change', this.onInput);
    this.onInput({ target: input.elementRef.nativeElement });

    input.ngControl.control?.events
      .pipe(
        filter((event) => event instanceof TouchedChangeEvent),
        tap(() => this.check()),
        takeUntilDestroyed(this.destroyRef),
      )
      .subscribe();

    input.ngControl.valueChanges
      ?.pipe(
        tap(() => {
          if (!input.ngControl.value && this.elementRef.nativeElement.classList.contains('is-value')) {
            this.renderer.removeClass(this.elementRef.nativeElement, 'is-value');
          }
          this.onInput({ target: input.elementRef.nativeElement });
        }),
        takeUntilDestroyed(this.destroyRef),
      )
      .subscribe();

    input.ngControl.statusChanges
      ?.pipe(
        startWith(input.ngControl.status),
        tap((status: FormControlStatus) => {
          this.isDisabled = status === 'DISABLED';
          this.disable();
        }),
        takeUntilDestroyed(this.destroyRef),
      )
      .subscribe();
  }

  ngOnDestroy(): void {
    const input = this.input();
    if (!input) {
      return;
    }

    input.elementRef.nativeElement.removeEventListener('click', this.onFocusin);
    input.elementRef.nativeElement.removeEventListener('focusout', this.onFocusout);
    input.elementRef.nativeElement.removeEventListener('input', this.onInput);
    input.elementRef.nativeElement.removeEventListener('change', this.onInput);
  }

  private onFocusin = () => {
    if (!this.isDisabled) {
      this.renderer.addClass(this.elementRef.nativeElement, 'is-pressed');
    }
  };

  private onFocusout = () => {
    if (!this.isDisabled) {
      this.renderer.removeClass(this.elementRef.nativeElement, 'is-pressed');
    }
    this.check();
  };

  private onInput = (event: Event | { target: HTMLInputElement }) => {
    if (!this.isDisabled) {
      const target = event.target as HTMLInputElement;

      if (target.value?.length > 0) {
        this.renderer.addClass(this.elementRef.nativeElement, 'is-value');
      } else {
        this.renderer.removeClass(this.elementRef.nativeElement, 'is-value');
      }

      this.check();
    }
  };

  private disable(): void {
    if (this.isDisabled) {
      this.renderer.addClass(this.elementRef.nativeElement, 'is-disabled');
    } else {
      this.renderer.removeClass(this.elementRef.nativeElement, 'is-disabled');
    }
  }

  private check(): void {
    if (this.input().ngControl.touched) {
      if (this.input().ngControl.errors) {
        this.renderer.addClass(this.elementRef.nativeElement, 'is-invalid');
      } else {
        this.renderer.removeClass(this.elementRef.nativeElement, 'is-invalid');
      }
    }
  }
}
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Так как input является потомком, ищем его после рендера и добавляем обработчики:

input.elementRef.nativeElement.addEventListener('click', this.onFocusin);
input.elementRef.nativeElement.addEventListener('focusout', this.onFocusout);
input.elementRef.nativeElement.addEventListener('input', this.onInput);
input.elementRef.nativeElement.addEventListener('change', this.onInput);
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Листенеры:

  • onFocusin - фосус;
  • onFocusout - блюр;
  • onInput - ввод значения в input.

Также подписываемся на изменение состояния:

   input.ngControl.control?.events
      .pipe(
        filter((event) => event instanceof TouchedChangeEvent),
        tap(() => this.check()),
        takeUntilDestroyed(this.destroyRef),
      )
      .subscribe();

    input.ngControl.valueChanges
      ?.pipe(
        tap(() => {
          if (!input.ngControl.value && this.elementRef.nativeElement.classList.contains('is-value')) {
            this.renderer.removeClass(this.elementRef.nativeElement, 'is-value');
          }
          this.onInput({ target: input.elementRef.nativeElement });
        }),
        takeUntilDestroyed(this.destroyRef),
      )
      .subscribe();

    input.ngControl.statusChanges
      ?.pipe(
        startWith(input.ngControl.status),
        tap((status: FormControlStatus) => {
          this.isDisabled = status === 'DISABLED';
          this.disable();
        }),
        takeUntilDestroyed(this.destroyRef),
      )
      .subscribe();
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Autocomplete

Реализуем autocomplete:

mkdir src/app/ui/autocomplete
mkdir src/app/ui/autocomplete/lib
echo >src/app/ui/autocomplete/index.ts
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Выполним команду:

yarn ng g c autocomplete
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Разметка и стили:

<baf-input-control cdkOverlayOrigin #trigger="cdkOverlayOrigin">
  <label baf-label [attr.for]="options().id">{{ options().label }}</label>
  <input
    #input
    baf-input
    type="text"
    [bafInputDisplay]="options().inputDisplayFn"
    [id]="options().id"
    [formControl]="control()"
    [placeholder]="options().placeholder ?? ''"
    (click)="onOpen()"
    (input)="onInput($event)"
  />
</baf-input-control>

<ng-template
  cdkConnectedOverlay
  [cdkConnectedOverlayOrigin]="trigger"
  [cdkConnectedOverlayOpen]="open()"
  [cdkConnectedOverlayWidth]="width"
  [cdkConnectedOverlayOffsetY]="1"
  (overlayOutsideClick)="onClose()"
>
  <div class="autocomplete-overlay">
    @for (option of data() | async; track option.id; let index = $index) {
      <a class="autocomplete-option" [innerHTML]="options().displayFn(option, index)" (click)="onSelect(option)"></a>
    }
  </div>
</ng-template>
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.autocomplete-overlay {
  background-color: var(--md-sys-color-surface-variant);
  color: var(--md-sys-color-on-surface-variant);
  width: 100%;
  padding: 1rem;
  border-radius: 0.25rem;
  box-shadow: 0 2px 5px 0 rgba(0, 0, 0, 0.15);
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.autocomplete-option {
  text-decoration: none;
  padding: 0.5rem;
  color: var(--md-sys-color-on-surface-variant);
  cursor: pointer;

  &:not(:last-child) {
    border-bottom: 1px solid var(--md-sys-color-surface);
  }

  &:hover {
    color: var(--md-sys-color-primary-container);
  }
}
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Логика компонента:

import { CdkConnectedOverlay, CdkOverlayOrigin } from '@angular/cdk/overlay';
import { AsyncPipe, NgForOf } from '@angular/common';
import type { Signal } from '@angular/core';
import { ChangeDetectionStrategy, Component, ElementRef, input, output, signal, viewChild } from '@angular/core';
import type { FormControl } from '@angular/forms';
import { ReactiveFormsModule } from '@angular/forms';
import type { Observable } from 'rxjs';
import { take, tap } from 'rxjs';

import type { DisplayFn } from '@baf/core';
import { InputComponent, InputControlComponent, InputDisplayDirective } from '@baf/ui/input';
import { LabelComponent } from '@baf/ui/label';

// eslint-disable-next-line @typescript-eslint/no-explicit-any
export type AutocompleteVariant = Record<string, any> & { readonly id: number | string };

export interface AutocompleteOptions {
  readonly label: string;
  readonly placeholder?: string;
  readonly id: string;
  readonly key: string;
  readonly displayFn: DisplayFn;
  readonly inputDisplayFn: DisplayFn;
}

@Component({
  selector: 'baf-autocomplete',
  standalone: true,
  imports: [
    ReactiveFormsModule,
    CdkConnectedOverlay,
    CdkOverlayOrigin,
    InputComponent,
    NgForOf,
    AsyncPipe,
    InputControlComponent,
    InputDisplayDirective,
    LabelComponent,
  ],
  templateUrl: './autocomplete.component.html',
  styleUrl: './autocomplete.component.scss',
  changeDetection: ChangeDetectionStrategy.OnPush,
  host: {
    class: 'baf-input-control',
  },
})
export class AutocompleteComponent {
  readonly control = input.required<FormControl<string | AutocompleteVariant>>();
  readonly options = input.required<AutocompleteOptions>();
  readonly data = input.required<Observable<AutocompleteVariant[]>>();

  readonly changed = output<string>();
  readonly opened = output();
  readonly closed = output();

  readonly input: Signal<ElementRef<HTMLInputElement>> = viewChild.required('input', { read: ElementRef<HTMLInputElement> });

  readonly open = signal<boolean>(false);

  get width(): string {
    return this.input().nativeElement.clientWidth > 200 ? `${this.input().nativeElement.clientWidth}px` : '200px';
  }

  onOpen(): void {
    if (!this.open()) {
      this.open.set(true);
      this.opened.emit();
    }
  }

  onClose(): void {
    this.closed.emit();
    this.open.set(false);

    this.data()
      .pipe(
        take(1),
        tap((options) => {
          if (
            options.length &&
            this.control().value &&
            (typeof this.control().value === 'string' || JSON.stringify(this.control().value) !== JSON.stringify(options[0]))
          ) {
            this.control().patchValue(options[0], { emitEvent: false });
          }
        }),
      )
      .subscribe();
  }

  onInput(event: Event): void {
    this.changed.emit((event.target as HTMLInputElement).value);
  }

  onSelect(option: AutocompleteVariant): void {
    this.control().patchValue(option, { emitEvent: false });
    this.closed.emit();
    this.open.set(false);
  }
}
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Суть работы следующая:

  • при клике на поле показать выпадающее окно;
  • при вводе значений, вывести подсказки.

Методы:

  • onOpen - показать окно;
  • onInput - ввод значения;
  • onSelect - выбор подсказки;
  • onClose - событие закрытия.

Показанных компонентов достаточно, чтобы перейти к разработке страниц.

Ссылки

Все исходники находятся на github, в репозитории - github.com/Fafnur/buy-and-fly

Демо можно посмотреть здесь - buy-and-fly.fafn.ru/

Мои группы: telegram, medium, vk, x.com, linkedin, site

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