Main Thread Checker: UI API called on background thread.

[Ruckt]

I got the following console log warning from using your chart. When I wrap it in a block to be executed on the main thread, I no longer get that warning. Would you be able to fix it on your end so I don't have to fork it?

[liuxuan30]

I don't think that what we need to fix. Any UI related task must be executed on main thread is a must know thing.

[Ruckt]

Well, if its a known thing that all UI tasks must be executed on the main thread, why are you not making sure its all on there in your pod? It's a known thing that when a problem arises in code, you go through the due diligence to find the cause to prevent it from happening again.

[liuxuan30]

Well, that will make the library have code that's not its concern.
If what you said correct, that's apple's duty to check all UI tasks on main thread, not ours. But as you see, Apple just warns you instead of do the work for you.
I will admit if that can be done, things will be lot of easier.

[Ruckt]

Apple is warning for a reason - because something is not up to its expectations. Or its not perfect and needs help - it only discovers its on the background thread after execution. That's where you come in to fix it.

[jjatie]

Looking at Thread 12 in your screenshot, it looks like you are receiving information on a background thread and trying to update your chart from there. It is your responsibility to ensure that you're calling methods that update the visual representation of the Chart on the main thread, just as it's your responsibility to ensure all other UI calls are done on the main thread.

If you feel this is not the case, you should file a bug report with Apple as almost none, if not none, of their UI calls are automatically rerouted to the main thread.

[Ruckt]

Thank you @jjatie for helping me find the problem. I was too busy distracted by the code and not the threads on the left, which display the method being called that triggers the warning.... Was able to put that on the main thread to eliminate the warning. It was the clear method I was calling on the background while the graph was being drawn on the main.