title: Upgrade Ngx-admin to Angular 9
body: <p>I'm trying to upgrade my project based on ngx admin from angular 8 to 9.
  I follow the angular.io guide, also I follow this step suggested by guide:</p>
  
  <pre><code>"If you are a library author and you had a method returning ModuleWithProviders (typically via a method named forRoot()), you will need to specify the generic type. Learn more angular.io"
  </code></pre>
  
  <p>Then I upgrade all nebular components to version 5.0.0. Then I upgrade ng2-smart-table to 1.6 version and remove ng2-completer and install @akveo/ng2-completer. (see <a href="https://github.com/akveo/ng2-smart-table/pull/1140" rel="nofollow noreferrer">https://github.com/akveo/ng2-smart-table/pull/1140</a>)</p>
  
  <p>Now, by running ng serve I have these errors:</p>
  
  <pre><code>ERROR in src/app/pages/pages.module.ts:22:12 - error NG1010: Value at position 4 in the NgModule.imports of PagesModule is not a reference: [object Object] 
  
   22   imports: [
                 ~
   23     PagesRoutingModule,
      ~~~~~~~~~~~~~~~~~~~~~~~
  ...
   27     AuthModule.forRoot(),
      ~~~~~~~~~~~~~~~~~~~~~~~~~
   28   ],
      ~~~
  src/app/app.module.ts:39:12 - error NG1010: Value at position 4 in the NgModule.imports of AppModule is not a reference: [object Object]
  
   39   imports: [
                 ~
   40     BrowserModule,
      ~~~~~~~~~~~~~~~~~~
  ...
   57     CoreModule.forRoot(),
      ~~~~~~~~~~~~~~~~~~~~~~~~~
   58   ],
      ~~~
  src/app/app.component.ts:13:14 - error NG8001: 'router-outlet' is not a known element:
  1. If 'router-outlet' is an Angular component, then verify that it is part of this module.
  2. If 'router-outlet' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '@NgModule.schemas' of this component to suppress this message.
  
  13   template: '&lt;router-outlet&gt;&lt;/router-outlet&gt;',
                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  src/app/pages/pages.component.ts:18:5 - error NG8001: 'ngx-one-column-layout' is not a known element:
  1. If 'ngx-one-column-layout' is an Angular component, then verify that it is part of this module.
  2. If 'ngx-one-column-layout' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '@NgModule.schemas' of this component to suppress this message.   
  
  18     &lt;ngx-one-column-layout&gt;
         ~~~~~~~~~~~~~~~~~~~~~~~
  src/app/pages/pages.component.tsm:19:7 - error NG8001: 'nb-menu' is not a known element:
  1. If 'nb-menu' is an Angular component, then verify that it is part of this module.
  2. If 'nb-menu' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '@NgModule.schemas' of this component to suppress this message.
  
  19       &lt;nb-menu [items]="menu"&gt;&lt;/nb-menu&gt;
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  src/app/pages/pages.component.ts:19:16 - error NG8002: Can't bind to 'items' since it isn't a known property of 'nb-menu'.
  1. If 'nb-menu' is an Angular component and it has 'items' input, then verify that it is part of this module.
  2. If 'nb-menu' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '@NgModule.schemas' of this component to suppress this message.
  
  19       &lt;nb-menu [items]="menu"&gt;&lt;/nb-menu&gt;
                    ~~~~~~~~~~~~~~
  src/app/pages/pages.component.ts:20:7 - error NG8001: 'router-outlet' is not a known element:
  2. If 'router-outlet' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '@NgModule.schemas' of this component to suppress this message.
  
  20       &lt;router-outlet&gt;&lt;/router-outlet&gt;
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  </code></pre>
  
  <p>Where is the problem?</p>
  
  <p>Thank you very much in advance</p>
  
  <p>Andrea</p>