bug(cdk/overlay): Output isn't recognized as a signal

[theoarav]

Is this a regression?

• Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

No response

Description

When trying to bind output through a component instanciated with @angular/cdk and passed to ng-dynamic-component library, the signal output isn't recognized as a Signal output.

I opened an issue on ng-dynamic-component: gund/ng-dynamic-component#527

Reproduction

StackBlitz link: https://stackblitz.com/edit/stackblitz-starters-cwmkaoqj
Steps to reproduce:

1. Click on Open Overlay button
2. Click on Output signal inside the overlay

Expected Behavior

The button should've worked the same as the one outside of the overlay.

Actual Behavior

An console error indicating that the library ng-dynamic-component doesn't recognize the output.

Environment

• Angular: 19
• CDK/Material: 19
• Browser(s): Chrome Version 137.0.7151.68 (Official Build) (x86_64)
• Operating System (e.g. Windows, macOS, Ubuntu): macOS

[gund]

Just want to clarify that the actual issue seems to be with the DI on the CDK Overlay and signal output bug is a derivative symptom.

Just to quote from my original comment:

For whatever reason when your component is rendered in the overlay angular resolves ComponentIO service to a ClassicComponentIO instead of the SignalComponentIO, which is why it's not working with signal outputs.
Unfortunately I cannot find a reason why it's not seeing a correct service in this case, potentially something to do with how DI works in the overlay context, which I do not understand.

Basically library relies on DI to resolve a strategy of how component inputs/outputs are resolved and by default it does not work with signals, for compatibility reasons with older angular versions.
Then applications can opt-in for a different strategy which adds support for signal based outputs by swapping default strategy with a different one via the global NgModule import which sets up the necessary providers.

And this works just fine normally, but when a dynamic component is rendered inside of the CDK Overlay - the strategy is resolved to a default one and signal outputs are not working there anymore.

My understanding is that global DI providers must be the same everywhere across the angular app but this behavior shows that something works differently with CDK Overlay DI wise which I do not understand.

So hopefully you can shine more light on this behavior and we can figure out how to properly fix it. Cheers!

[crisbeto]

You can pass a different injector when creating the portal so that it's able to resolve the strategy. If no injector is passed in, it'll use the root injector.

[gund]

Yeah you are right it's actually working as expected when the module is registered at the root app level, last time I tried the stackblitz just did not rebuild and it did not work. Sorry for the extra issue.