How do I prevent my progress dialog getting locked up?

[Lawyno]

Hi there :)

Here are some infos about my "project":
I have the "honor" to write some scripts (VBScript) for some application developed by another company. In this application there is limited support for creating and showing dialogs. But the customers want it. So we have to create those dialogs in class libraries to be able use them in the scripts.

Until now, we had ActiveX/COM libraries created with VB6.0. But now, the customers want us to port them to .NET.

And here is my problem:
I ported some sort of progress dialog into the .NET world. It runs fine... as long as no one wants a "cancel" button.

The progress dialog should be accessible from the script like this:

Dim intIndex
Dim objDialog
Set objDialog = CreateObject("ProgressBar.Dialog")
 
'setup dialog
Call objDialog.SetCaption("Test")
Call objDialog.ShowCancelButton(True)
 
'show dialog
Call objDialog.Show()
 
'do some work in a loop
Do While WorkIsAvailable()
    Call DoWork()
    If objDialog.IsCanceled() Then
        Exit Sub
    End If
    Call objDialog.advanceProgress()
Loop
 
'hide dialog
Call objDialog.Hide()
 
 

So I created a dialog form like this:

// (C# code; limited to the attributes and methods that seem important to me)
 
public partial class Dialog : Form
{
    private bool _isCanceled = false;
 
    public void advanceProgress() {
        this.progressBar.Increment(1);
    }
 
    private void cmdCancel_Click(object sender, EventArgs e) {
        this.cmdCancel.Enabled = false;
        this._isCanceled = true;
    }
 
    public bool isCanceled() {
        return this._isCanceled;
    }
}
 

As said. This works. But the dialog seems to get too busy, handling GUI requests like pushing that "cancel" button, which is important.

Inserting "WScript.sleep(1)" in my test script running from desktop solved the problem, but "WScript" is not available in that application the script should run in.

And I think it would be better, to have the dialog form "lockup-save", instead of adding some pause in each script.

While searching for answers, I got some info about background workers and threads (they seem to be like those in JAVA), but I don't think, these can help me here, since I can't execute my work in a seperate thread. If I could tell the GUI to run in another thread... ;)

Well, perhaps someone of you guys can help me with this one ;)

Thanks & have a nice day :)

Lawyno

[Lawyno]

No expert here, who could help me? :'(

[IanWright]

Well you could add in Application.DoEvents() within the threading loop...

However that isn't a very nice solution. The more important question really is why can't you do the work in a seperate thread?

[Lawyno]

Well you could add in Application.DoEvents() within the threading loop...

Application.DoEvents() works really nice, thank you ;)

However that isn't a very nice solution. The more important question really is why can't you do the work in a seperate thread?

Well the work is done (and can only be done) by the script. So how could I put that work into a seperate Thread? Unfortunately I can't tell the host application to do so.