Call a service from a different component to display a message

Question

I have a shared component alert which displays different alerts (error, success..) that uses a service 'alertService'.

I have different components that uses the 'alertService'.

The alert component is called in the appComponent like so: <app-alert></app-alert>

When I call the service from another component the alert isn't displayed, it displays only when I call <app-alert></app-alert> in the component that call the service.

Answer 1

解决方案：我在app.module中提供alert服务，shared.module中提供。