WPF Threading Backgroundworker issue

Question

I have two different background thread who does similar thing but at different time in my WPF application. both are right now independent background worker.
1) first thread runs when you launch application, it downloads all images from connected printer to PC location.
2) second thread does the same thing  when use click on some link in my application. 
As both worker are independent, even though first thread's downloading process are still running, if user click on link the second thread start their work too 
What I would like to do is, when user click on 2nd thread, is there any way I will know about status of first thread ? I mean if i know that first thread is doing it's work then I don't want to even start second thread. I need only second thread when first
one got cancelled by some other reason.
I heard about Mutex but I dont know how it works. Pls share ur idea and some example if you know how to handle this.
Thanks
Dee 

Answer 1

Why even have a second instance of BackgroundWorker, why not just reuse the one that you already have?  At the very least re-use the variable, so that you remember to dispose of any previous instance.  If you are creating a new BackgroundWorker
each time, without disposing of any previous instances, you are definitely going to have memory leaks.
Something along these lines should work for you:
Define a private property to track the BackgroundWorker:
private BackgroundWorker m_Worker;
Define your work and completed events:
private void Work(object sender, DoWorkEventArgs e)
// Do long running work
private void WorkDone(object sender, RunWorkerCompletedEventArgs e)
// Process the results
// Clean up
m_Worker.Dispose();
m_Worker = null;
And then your button click event, which I will leave up to you for the actual implementation for MVVM, if you are using it:
private void ButtonClick(object sender, RoutedEventArgs e)
if (m_Worker != null && m_Worker.IsBusy)
return;
m_Worker = new BackgroundWorker();
m_Worker.DoWork += new DoWorkEventHandler(Work);
m_Worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(WorkDone);
m_Worker.RunWorkerAsync();
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