1/*
2 * Copyright 2023, The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17import {Input} from '@angular/core';
18import {VariableHeightScrollStrategy} from './variable_height_scroll_strategy';
19
20export abstract class VariableHeightScrollDirective<T extends object> {
21  abstract scrollStrategy: VariableHeightScrollStrategy;
22
23  @Input()
24  set scrollItems(items: T[]) {
25    if (this.scrollItems !== items) {
26      this.scrollStrategy.updateItems(items);
27    }
28  }
29}
30