import { CommonModule } from '@angular/common' ; import { NgModule } from '@angular/core' ; import { NzDropDownModule } from 'ng-zorro-antd/dropdown' ; import { NzToolTipModule } from 'ng-zorro-antd/tooltip' ; import { ALAIN_THEME_BTN_KEYS , ThemeBtnComponent } from './theme-btn.component' ; const COMPONENTS = [ ThemeBtnComponent ] ; @ NgModule ( { imports : [ CommonModule , NzDropDownModule , NzToolTipModule ] , providers : [ { provide : ALAIN_THEME_BTN_KEYS , useValue : 'site-theme' } ] , declarations : COMPONENTS , exports : COMPONENTS } ) export class ThemeBtnModule { }