Open project folder/src/providers/config.service.ts file and change the following.
- onesignalAppIdString
- onesignalSenderIdString
It will enable Onesignal reception in your app
// Push Notification Settings
public onesignalAppIdString: string = '',
public onesignalSenderIdString: string = '',
Test Application
You can Create Onesignal AppId and Onesignal SenderId by following below link.