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Hi,
In MFC Dialog based application, I am calling SetTimer and in ontimer I am calling a function which is a long operation. In the same dialog I have cancel button, If I click cancel button , I need to abort the long operation happening in the ontimer. After going inside the ontimer function, I could not click the cancel button.
How to receive UI events when ontimer is executed?
The ontimer function is executing on the UI thread. Long operations should be run on a worker thread to prevent them from blocking the user interface.
Can I achieve my requirement without using timer?
Can I achieve my requirement without using timer?
Sure. Have the code in the worker thread check a flag to see if the long-running operation should be cancelled.
In the UI Thread you can set the flag when the user clicks the cancel button.
whether I need to create a new worker thread from main thread for executing long operation?
whether I need to create a new worker thread from main thread for executing long operation?
I already suggested using a worker thread. I don't understand your question.
when opening a dialog I need to execute long operation. I cannot call long operation function from oninitdialog,since it wont diaplay the dialog until the long operation completed thats why I used timer previously. Now are you suggesting me to create new thread using AfxBeginThread()?
Yes, AfxBeginThread is the MFC function to use.
Does it matter If your long running operation in a worker thread created by AfxBeginThread in OnInitDialog starts running before the dialog is visible?