カスタムコントロール

import {Component, model} from '@angular/core';
import {FormValueControl} from '@angular/forms/signals';

@Component({
  selector: 'app-basic-input',
  template: `
    <div class="basic-input">
      <input
        type="text"
        [value]="value()"
        (input)="value.set($event.target.value)"
        placeholder="Enter text..."
      />
    </div>
  `,
})
export class BasicInput implements FormValueControl<string> {
  /** The current input value */
  value = model('');
}

import {Component, model, ChangeDetectionStrategy} from '@angular/core';
import {FormCheckboxControl} from '@angular/forms/signals';

@Component({
  selector: 'app-basic-toggle',
  template: `
    <button type="button" [class.active]="checked()" (click)="toggle()">
      <span class="toggle-slider"></span>
    </button>
  `,
  changeDetection: ChangeDetectionStrategy.OnPush,
})
export class BasicToggle implements FormCheckboxControl {
  /** Whether the toggle is checked */
  checked = model<boolean>(false);

  toggle() {
    this.checked.update((val) => !val);
  }
}

import {Component, signal, ChangeDetectionStrategy} from '@angular/core';
import {form, FormField, required} from '@angular/forms/signals';
import {BasicInput} from './basic-input';
import {BasicToggle} from './basic-toggle';

@Component({
  imports: [FormField, BasicInput, BasicToggle],
  template: `
    <form novalidate>
      <label>
        Email
        <app-basic-input [formField]="registrationForm.email" />
      </label>

      <label>
        Accept terms
        <app-basic-toggle [formField]="registrationForm.acceptTerms" />
      </label>

      <button type="submit" [disabled]="registrationForm().invalid()">Register</button>
    </form>
  `,
  changeDetection: ChangeDetectionStrategy.OnPush,
})
export class Registration {
  registrationModel = signal({
    email: '',
    acceptTerms: false,
  });

  registrationForm = form(this.registrationModel, (schemaPath) => {
    required(schemaPath.email, {message: 'Email is required'});
    required(schemaPath.acceptTerms, {message: 'You must accept the terms'});
  });
}

import {Component, signal, ChangeDetectionStrategy} from '@angular/core';
import {form, FormField, required} from '@angular/forms/signals';
import {CustomInput} from './custom-input';
import {CustomToggle} from './custom-toggle';

@Component({
  selector: 'app-my-form',
  imports: [FormField, CustomInput, CustomToggle],
  template: `
    <form novalidate>
      <app-custom-input [formField]="userForm.username" />
      <app-custom-toggle [formField]="userForm.subscribe" />
    </form>
  `,
  changeDetection: ChangeDetectionStrategy.OnPush,
})
export class MyForm {
  formModel = signal({
    username: '',
    subscribe: false,
  });

  userForm = form(this.formModel, (schemaPath) => {
    required(schemaPath.username, {message: 'Username is required'});
  });
}

import {Component, model, input, ChangeDetectionStrategy} from '@angular/core';
import {FormValueControl, WithOptionalFieldTree, ValidationError, DisabledReason} from '@angular/forms/signals';

@Component({
  selector: 'app-stateful-input',
  template: `
    @if (!hidden()) {
      <div class="input-container">
        <input
          type="text"
          [value]="value()"
          (input)="value.set($event.target.value)"
          [disabled]="disabled()"
          [readonly]="readonly()"
          [class.invalid]="invalid()"
          [attr.aria-invalid]="invalid()"
          (blur)="touched.set(true)"
        />

        @if (invalid()) {
          <div class="error-messages" role="alert">
            @for (error of errors(); track error) {
              <span class="error">{{ error.message }}</span>
            }
          </div>
        }

        @if (disabled() && disabledReasons().length > 0) {
          <div class="disabled-reasons">
            @for (reason of disabledReasons(); track reason) {
              <span>{{ reason.message }}</span>
            }
          </div>
        }
      </div>
    }
  `,
  changeDetection: ChangeDetectionStrategy.OnPush,
})
export class StatefulInput implements FormValueControl<string> {
  // Required
  value = model<string>('');

  // Writable interaction state - control updates these
  touched = model<boolean>(false);

  // Read-only state - form system manages these
  disabled = input<boolean>(false);
  disabledReasons = input<readonly DisabledReason[]>([]);
  readonly = input<boolean>(false);
  hidden = input<boolean>(false);
  invalid = input<boolean>(false);
  errors = input<readonly WithOptionalFieldTree<ValidationError>[]>([]);
}

import {Component, signal, ChangeDetectionStrategy} from '@angular/core';
import {form, FormField, required, email} from '@angular/forms/signals';
import {StatefulInput} from './stateful-input';

@Component({
  imports: [FormField, StatefulInput],
  template: `
    <form novalidate>
      <label>
        Email
        <app-stateful-input [formField]="loginForm.email" />
      </label>
    </form>
  `,
  changeDetection: ChangeDetectionStrategy.OnPush,
})
export class Login {
  loginModel = signal({email: ''});

  loginForm = form(this.loginModel, (schemaPath) => {
    required(schemaPath.email, {message: 'Email is required'});
    email(schemaPath.email, {message: 'Enter a valid email address'});
  });
}

import {formatCurrency} from '@angular/common';
import {ChangeDetectionStrategy, Component, linkedSignal, model} from '@angular/core';
import {FormValueControl} from '@angular/forms/signals';

@Component({
  selector: 'app-currency-input',
  template: `
    <input
      type="text"
      [value]="displayValue()"
      (input)="displayValue.set($event.target.value)"
      (blur)="updateModel()"
    />
  `,
  changeDetection: ChangeDetectionStrategy.OnPush,
})
export class CurrencyInput implements FormValueControl<number> {
  // 数値 (1234.56) を格納します
  readonly value = model.required<number>();

  // 表示値 (「1,234.56」) を格納します
  readonly displayValue = linkedSignal(() => formatCurrency(this.value(), 'en', 'USD'));

  // 表示値からモデルを更新します
  updateModel() {
    this.value.set(parseCurrency(this.displayValue()));
  }
}

// 通貨文字列を数値に変換します (例: 「USD1,234.56」 -> 1234.56)
function parseCurrency(value: string): number {
  return parseFloat(value.replace(/^[^\d-]+/, '').replace(/,/g, ''));
}

export class NumberInput implements FormValueControl<number> {
  value = model<number>(0);

  // スキーマのバリデーションルールからの制約値
  required = input<boolean>(false);
  min = input<number | undefined>(undefined);
  max = input<number | undefined>(undefined);
}