FR: Add support for Angular Change detection and "OnPush" mode

[QuentinFchx]

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• [X] I have searched for duplicate or closed issues and discussions.
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• [X] I have tried deleting the node_modules folder and reinstalling my dependencies
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On which framework/platform are you having an issue?

Angular

Which UI component?

Authenticator

How is your app built?

angular cli (v15) / Node v18.15.0

What browsers are you seeing the problem on?

Firefox, Safari

Which region are you seeing the problem in?

eu-west-1

Please describe your bug.

When using the amplify-authenticator component inside a component with ChangeDetectionStrategy.OnPush, nothing is rendered.

What's the expected behaviour?

The amplify-authenticator component should take care of change detection on its own.

Help us reproduce the bug!

I've setup a sample repository : https://github.com/QuentinFchx/amplify-ui-change-detection

When you serve the project, you should see a blank page : the amplify-authenticator is not rendered.

As a workaround, you can uncomment the following lines at https://github.com/QuentinFchx/amplify-ui-change-detection/blob/main/src/app/app.component.ts#L24

this.unsubscribe = this.authenticator.subscribe(() => {
    this.cdRef.detectChanges();
}).unsubscribe;

AFAIK, the issue seems to come from https://github.com/aws-amplify/amplify-ui/blob/main/packages/angular/projects/ui-angular/src/lib/components/authenticator/components/authenticator/authenticator.component.ts#L89. I'm not sure what is the purpose of the hubSubject, but the callback is never called, thus :

• the detectChanges in the callback is never called
• isHandlingHubEvent is never set to true, thus the detectChanges of the authenticator subscription (a few lines below) is never called

Code Snippet

No response

Console log output

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Additional information and screenshots

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