Multiple Backgroundworker threads in a single Backgroundworker thread - multithreading

Question

I have an issue here with multi-threading. Tried using both backgroundworker and threads.
Objective: Select an item from a combo-box and click a button to trigger multiple backup file restores into the MSSQL Server. The intention is to popup as many popups as there are Backup files to restore. The main window starts a backgroundworker, showing the overall progress, while the child threads result in non-modal child popups representing each restoration process with progress. This works fine if run serially (without threads/backgroundworker). My intention is to run a bunch of parallel popups, so that the restoration is much more quick.
Problem Statement: My intention is to run a bunch of parallel popups, so that the restoration is much more quick instead of running serially. While trying to debug, its a chaotic break-point show that the Visual Studio shows up (perhaps to represent multiple threads in parallel). But the ultimate goal is not being achieved. Can anybody help me in this regard?
- Code Extracts
Here is the code extract, which I've done and this works in a serial fashion. But as soon as I put the code for multi-threading, nothing works. Only the popups appear, but no processing happens.
This is the button click event, which starts the whole process
private void btnSnapshot_Click(object sender, EventArgs e)
{
this.SetPanelEnabledProperty(false); // Disable All Controls on the main window
// Select the text against which the DATABASE Backup Files are to be picked
// Start the main background worker process, which in turn will trigger few other child threads
BGWrk.RunWorkerAsync(2000);
BGWrk.DoWork += new DoWorkEventHandler(BGWrk_DoWork);
BGWrk.ProgressChanged += new ProgressChangedEventHandler(BGWrk_ProgressChanged);
BGWrk.RunWorkerCompleted += new RunWorkerCompletedEventHandler
(BGWrk_RunWorkerCompleted);
BackgroundWorker helperBW = sender as BackgroundWorker;
BGWrk.WorkerReportsProgress = true;
BGWrk.WorkerSupportsCancellation = true;
}
private void BGWrk_DoWork(object sender, DoWorkEventArgs e)
{
BackgroundWorker helperBW = sender as BackgroundWorker;
int arg = (int)e.Argument;
//Call the method that invokes the popup window instances in a loop, for each file found for the SnapShotName selected in the combobox
ParallelRestoreSnapshot();
if (helperBW.CancellationPending)
{
e.Cancel = true;
}
}
// This method will create backgroundworker instances and in turn the Do_Work events of those backgroundworkers will call the popup against each backup file.
private bool ParallelRestoreSnapshot()
{
FileOperations FIO = new FileOperations();
if (SelectedSnapShot != null && SelectedSnapShot != "None")
{
string[] sBakFiles;
sBakFiles = FIO.GetListOfBackupFiles(sEntireBackupFilePath);
try
{
progressPopupsList = new List<FrmProgressPopup>();
for (int aIndex = 0; aIndex < sBakFiles.Length; aIndex++)
{
BackgroundWorker bgPopups = new BackgroundWorker();
BAKFileName = sBakFiles[aIndex];
bgPopups.RunWorkerAsync(2000);
bgPopups.DoWork += new DoWorkEventHandler(bgPopups_DoWork);
bgPopups.ProgressChanged += new ProgressChangedEventHandler(bgPopups_ProgressChanged);
bgPopups.RunWorkerCompleted += new RunWorkerCompletedEventHandler
(bgPopups_RunWorkerCompleted);
bgPopups.WorkerReportsProgress = true;
bgPopups.WorkerSupportsCancellation = true;
}
retVal = true;
}
catch (Exception exc)
{
MessageBox.Show("Error while Restoring: " + exc.Message, "Exception encountered", MessageBoxButtons.OK, MessageBoxIcon.Error);
//goto NextDB;
return false;
}
}
FIO = null;
return retVal;
}
// This DoWork event calls a method GeneratePopupInstances which makes copies of a window, which is shown as non-modal
private void bgPopups_DoWork(object sender, DoWorkEventArgs e)
{
BackgroundWorker helperBW = sender as BackgroundWorker;
int arg = (int)e.Argument;
//BackgroundProcessLogicMethod(helperBW, arg);
GeneratePopupInstances();
if (helperBW.CancellationPending)
{
e.Cancel = true;
}
}