Is it possible to declare a component with a generic type in Angular 4?
The following code causes build errors:
export class MyGenericComponent<T> implements OnInit {
@Input() data: BehaviorSubject<T[]>;
//...
}
The error when executing ng serve
is:
ERROR?in?C:/.../my-generic.module.ts?(5,10): Module?'"C:/.../my-generic.component"'?has?no?exported?member?'MyGenericComponent'.
Example:
The following example is an attempt to implement a generic data table where @Input() data
changes from one component 'calling this component' to another.
The question is could BehaviorSubject<any[]>
be changed to BehaviorSubject<T[]>
where T
would be the generic type passed to the component?
@Component({
selector: 'my-data-list',
templateUrl: './data-list.component.html',
styleUrls: ['./data-list.component.css']
})
export class DataListComponent implements OnInit {
@Input() data: BehaviorSubject<any[]>;
@Output() onLoaded = new EventEmitter<boolean>();
private tableDataBase : TableDataBase = new TableDataBase();
private dataSource : TableDataSource | null;
constructor() { }
ngOnInit() {
this.tableDataBase.dataChange = this.data;
this.dataSource = new TableDataSource(this.tableDataBase);
this.onLoaded.emit(true);
}
}
class TableDataBase {
dataChange: BehaviorSubject<any[]> = new BehaviorSubject<any[]>([]);
get data(): any[] {
return this.dataChange.value;
}
}
class TableDataSource extends DataSource<any> {
constructor(private tableDataBase: TableDataBase) {
super();
}
connect(): Observable<any[]> {
return Observable.of(this.tableDataBase.data);
}
disconnect() {}
}
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