问Angular 2-无法绑定来自HTTP Get请求的数据

EN

 public permission(module: string): Observable<Permissions[]> {
    return this.http
    .get('api-url')
    .map((response: Response) => {
       return <Permissions[]>response.json();
       })
}

_permissionsView: Permissions[];

ngOnInit() {
    this.getPermissions();
}

getPermissions() {
    this._commonService.permission('module')
    .subscribe(
        resultsArray => {
            this._permissionsView = resultsArray;
            console.log(this._permissionsView);
        },
        error => {"Error: " + error }
    )
}

<kendo-grid [kendoGridBinding]="_permissionsView">
            ....
</kendo-grid>