Quick Fix: As per the documentation, effects always run one time. It’s recommended to create the effect in the constructor, ngOnInit, ngAfterViewInit, etc., to ensure it’s created in the injector context. Additionally, you can provide an injector via the options parameter.
The Solutions:
Solution 1: Ensuring Signal Computation After Input Initialization
The key here is to understand that a signal effect runs only once. This means that the effect may be executed during the initial access of the signal. This differs from RxJS’s subscribe method, which allows multiple subscriptions.
It is not guaranteed when the effect will run, but it is ensured that it won’t run before the signal is created. To ensure that the input is initialized before the signal computation, you can create the effect in the constructor, ngOnInit, or ngAfterViewInit method.
In the options parameter, you can provide the injector if it is not present in the current context.
Q&A
What is the actual timing for the signal computation to occur in Angular 16?
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The effect always runs one time, so the effect can be the first time the signal is accessed.
Will the effect run at a specific time?
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No, there is no guarantee when the effect will run.
Where can I create an effect?
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You can create an effect in the constructor, ngOnInit, ngAfterViewInit etc.
Video Explanation:
The following video, titled "Episode 23/50: Zoneless without Signals, Roadmap, Signal Inputs ...", provides additional insights and in-depth exploration related to the topics discussed in this post.
The Angular team published the project plan for the Signals/Reactivity roadmap, where we can see what tasks they are currently working on ...
