Helpful tip for childSlot

[longqingzhao]

I have an idea for this project.
when call childSlot in Dispatcher.IO before。check current Thread==''main''
This is helpful to resolve bug faster!

[arkivanov]

There are already main thread checks implemented. Could you please elaborate?

[longqingzhao]

You are right. But when I initialize a childStack in other thread unconsciously.

For example:

1.When I call dialogNavigation.navigate { state }. It will be initialized in io coroutineScope and throw error about check main thread

2.When I call dialogNavigation.navigate { state }. It will be initialized in UI coroutineScope and my app closed with nothing error.

When I initialize childStack by these error way,I need to analysis source code and debug.

If check main thread for here,I can know the cause first. It's friendly for some developer.

[arkivanov]

Perhaps, we could an additional main thread check.

Btw, your first code snippet has a mistake. Please don't use get() = for navigation properties, just assign the value directly val state: Value<ChildSlot<...>> = childSlot(...).

[arkivanov]

Sorry but I still don't see where is the issue in your case. The case #1 has the main thread check already and prints the error in the logs because of the background thread. The case #2 has the main thread check as well and should work correctly because of the main thread.

[longqingzhao]

In case #1, I indeed have a main thread check and an error message is thrown. However, the error message did not specifically mention that val state: Value<ChildSlot<...>> = childSlot(...) cannot be used on a background thread.
I spent a long time searching for the issue and trying out various solutions before realizing that my val state: Value<ChildSlot<...>> = childSlot(...) was being executed on a background thread.

The problem is that while there is a main thread check, it does not explicitly indicate that childSlot must be run on the main thread in error.

Therefore, I suggest that a main thread check should be performed inside the childSlot method and an exception should be thrown accordingly. This would be very user-friendly.

[arkivanov]

Ok, so the actual issue is because the property is accessed on a background thread. It makes sense to add the additional check. Thanks for raising.