MFC SDI Windows Explorer type application related query?

Hi
My existing project is an MFC Windows explorer type SDI application.
Now there is a situation where a heavy process(reading hard disk) goes on
for say 2-3 minutes & then based on this process a running tree of existing
dirs in the system is created.
Also at the same time the status bar panes 0 & 1 are updated.
Pane 0 shows the count of total dirs found & added to tree.
Pane 1 shows the total size of the folders added to tree.


Now there are few problems here:

1.-->At the time the heavy process is going on & the user switches to some
other application and then returns back, the gui of my application
disappears & a
blank white screen is displayed.

2.-->At the time the running tree is being created, if the user drops down
some menu item or presses the left/right mouse button the creation of the
running tree is stopped.

I want to solve these two issues.

After doing some surfing on the net i thing that using the concept of the
Multithreading will solve my problem.

Waiting for suggestions

Best Regards







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