Assignment in afterCreate hook being disregarded in React component

[davetapley]

Placeholder for linking to in my code, repro incoming 🤞🏻

For now, to be absolutely 100% sure:

The afterCreate hook is a regular action in the sense that:
if I make an assignment in it then it should update the model, right?

I don't see anything saying otherwise in the docs

Because in my app I can see it hitting the afterCreate correctly, and assigning a new value (I'm doing some unit normalization for units), but when I reference the model in a React component I'm still getting the original value.

I see that in reconciliation it says:

If an object is reconciled ... life-cycle hooks are not fired because applying a snapshot results just in an existing tree node being updated

But I'm not doing anything explicit with snapshots, I'm just using Map.put.

[mattruby]

I think you might be able to use https://mobx-state-tree.js.org/overview/hooks#snapshot-processing-hooks To get in front of manipulating incoming data.

…

On Wed, Apr 9, 2025 at 3:23 PM Dave Tapley ***@***.***> wrote: *Placeholder for linking to in my code, repro incoming* 🤞🏻 For now, to be absolutely 100% sure: The afterCreate hook is a regular action in the sense that: if I make an assignment in it then it should update the model, right? I don't see anything saying otherwise in the docs <https://mobx-state-tree.js.org/overview/hooks> Because in my app I can see it hitting the afterCreate correctly, and assigning a new value (I'm doing some unit normalization for units <https://github.com/convert-units/convert-units>), but when I reference the model in a React component I'm still getting the original value. I see that in reconciliation <https://mobx-state-tree.js.org/concepts/reconciliation#docsNav> it says: If an object is reconciled ... life-cycle hooks are not fired because applying a snapshot results just in an existing tree node being updated But I'm not doing anything explicit with snapshots, I'm just using Map.put . — Reply to this email directly, view it on GitHub <#2268>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AABCW4STBIO6QLOZQMLKZAT2YV6SRAVCNFSM6AAAAAB2Z42WUWVHI2DSMVQWIX3LMV43ASLTON2WKOZSHE4DGOBTHAZTEOA> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***> *davetapley* created an issue (mobxjs/mobx-state-tree#2268) <#2268> *Placeholder for linking to in my code, repro incoming* 🤞🏻 For now, to be absolutely 100% sure: The afterCreate hook is a regular action in the sense that: if I make an assignment in it then it should update the model, right? I don't see anything saying otherwise in the docs <https://mobx-state-tree.js.org/overview/hooks> Because in my app I can see it hitting the afterCreate correctly, and assigning a new value (I'm doing some unit normalization for units <https://github.com/convert-units/convert-units>), but when I reference the model in a React component I'm still getting the original value. I see that in reconciliation <https://mobx-state-tree.js.org/concepts/reconciliation#docsNav> it says: If an object is reconciled ... life-cycle hooks are not fired because applying a snapshot results just in an existing tree node being updated But I'm not doing anything explicit with snapshots, I'm just using Map.put . — Reply to this email directly, view it on GitHub <#2268>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AABCW4STBIO6QLOZQMLKZAT2YV6SRAVCNFSM6AAAAAB2Z42WUWVHI2DSMVQWIX3LMV43ASLTON2WKOZSHE4DGOBTHAZTEOA> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>