ionic2 + cordova problem summary

1. The click events of elements such as checkboxes and buttons are triggered two or more times: because IonicModule.forRoot() is called two or more times, remove the IonicModule.forRoot() call of the child module.
2. ionic cordova build ios --prod packaging is successful and the style is not displayed normally (it will appear after re-executing cnpm install after node_modules is deleted): using npm install to install dependencies can solve this problem.
3. Jiguang push: mainly IOS, certificate application, set push after packaging, if plug not install appears after packaging, the reason is that the plug-in is not installed and then reinstalled and packaged
4. The carousel image should not be acquired asynchronously, but can be acquired and passed to the relevant page in advance
5. If you want to do some page jumps in the service you designed yourself, you need to set it in app.component.ts

   // app.component.ts
   this.httpService.dismiss.subscribe((value) => {
           this.rootPage = LoginPage;
   });
   // httpService.ts
    this.dismissObserver = null;
       this.dismiss = Observable.create(observer => {
         this.dismissObserver = observer;
       });