Xojo.Threading.Thread.Suspend
From Xojo Documentation
Method
Puts the thread in a suspended state where it will no longer run. You can allow the thread to continue by calling Resume.
Notes
When a thread is suspended, it is not allocated any processing time, regardless of its priority.
Sample Code
LongRunningThread.Suspend
// Other code goes here
LongRunningThread.Resume
// Other code goes here
LongRunningThread.Resume