Detect if a building is currently training a unit.

[Reaper51]

How can you detect if a building is currently training a unit?
When a building starts training, it removes an ability from the building.
When a building finishes/cancels training it adds the ability again.
BUT if you can cancel a unit which is not building and is in the building queue it gives the ability back which I do not want. Is there a way to fix this?

 

[Maker]

You could catch the train orders, cancel orders and when a unit finishes training. Keep track of the number of units being trained with an integer.

 

[Reaper51]

You could catch the train orders, cancel orders and when a unit finishes training. Keep track of the number of units being trained with an integer.

Good idea I will try and see if it works, but how would you be able to tell between a unit that is currently in training to the ones that are queued?