William,
I want to thank you for all you're help, you managed to get me on the
right track. I have solved the problem by foing the following :
-----------------------------------------------------------------------------------------------------------------------
// Used to store the nodes as they are populated
private Stack<TreeMenuNode> tn = new Stack<TreeMenuNode>();
private void frmMenuMaint_Load(object sender, EventArgs e)
{
this.Visible = false;
Thread _workerThread = new Thread(loadMenuTree);
_workerThread.Start();
using (Utilties.frmLogin frm = new Utilties.frmLogin(......)
{
frm.ShowDialog();
if (frm.DialogResult == DialogResult.OK)
{
this.Visible = true;
}
else
{
MessageBox.Show(.......);
Application.Exit();
}
}
try
{
// If the thread has not finished yet
// wait up to 30 secs for it to complete
if (_workerThread.IsAlive)
_workerThread.Join(30000);
} catch (Exception ex)
{
// Something has gone wrong
MessageBox.Show(......);
ev.WriteEntry(.......);
Application.Exit();
}
// Now add the nodes to the UI
lock (typeof(Stack<TreeMenuNode>))
{
while (tn.Count > 0)
tvMenus.Nodes.Add((TreeMenuNode)tn.Pop());
}
In essece the started Background thread finds all the top level nodes
(TreeMenuNodes in my case -- Inherited from TreeNodes), the task builds each
node and all its siblings attached to it, it then locks the stack var and
pushes the node onto it. This will repeat for each top level node defined
(in my case only 6 at the moment). When the user is logged on, I check to
see of the task has finished, if not block on the task for up to 30sec
(ample time). When the task is done, i just pop the nodes of the stack and
add them to the UI on the UI thread. I think this is the simplest safest
solution.
If you are interested I also got good info from the following 3 URLs
http://weblogs.asp.net/justin_rogers...es/126345.aspx http://code.snapstream.com/mediawiki...kground_Thread http://msevents.microsoft.com/CUI/Ev...&Culture=en-US
Thank you again for you're invaluable assistance,
Jamie
"William Stacey [MVP]" <william.stacey@gmail.com> wrote in message
news:OH%23tYLuXGHA.1084@TK2MSFTNGP04.phx.gbl...[color=blue]
> Couple issues here I think I see. Your worker thread is not actually
> doing
> much here as you turn around and Invoke right way. Everything in the
> Invoke{} is being done on the UI thread so it is blocking other UI
> events -
> that must be the issue you see.
> If possible, you want to refactor your work out from your UI work. In
> your
> Thread, do the work loop and Invoke only the UI updates.
> Such as
>
> new Thread(delegate
> {
> while(true)
> {
> // Read line 1.
> // Calc
> if ( done )
> break;
>
> // Update UI
> this.Invoke((ThreadStart)delegate()
> {
> this.treeview.update(xyz)/
> }
> }
> }).Start();
>
> frm.ShowDialog();
> ...
> --
> William Stacey [MVP]
>
> "Jamie Bissett" <jameibissett@yahoo.com> wrote in message
> news:uVG6ThsXGHA.3448@TK2MSFTNGP04.phx.gbl...
> | This is the Form Load Code
> |
> | private void frmMenuMaint_Load(object sender, EventArgs e)
> | {
> | // Hide the Main form (this has the Treeviews on this form
> | this.Visible = false;
> | // Create an instance of the Login Form
> | using (Utilties.frmLogin frm = new
> |
> Utilties.frmLogin(ConfigurationManager.ConnectionS trings["Eden_POS_Management.Properties.Settings.HotelConn ectionString"].ConnectionString))
> | {
> | new Thread(delegate()
> | {
> | this.Invoke((ThreadStart)delegate()
> | {
> | // This class performs the intense loading of the
> | tree view
> | // It initialy perofms a
> | // tvMenus.SuspendLayout();
> | // tv.BeginUpdate();
> | // and resumes them on completion
> | LoadTreeViews lt = new LoadTreeViews();
> | lt.loadMenuTree(Plans, tvMenus);
> | });
> | }).Start();
> | Thread.Sleep(150); // Doesn;t seem to make any
> | difference
> | // Validate the User, the Dialog will only return the OK
> | result if the User Credentials are vaidated
> | // This is the dialog that is Painting Slowly, it paints
> | immediatley if I dont have the Load Treeview
> | // therefor there is nothing slowing it down in this
> | dialog
> | frm.ShowDialog();
> | if (frm.DialogResult == DialogResult.OK)
> | {
> | this.Visible = true;
> | }
> | else
> | {
> | MessageBox.Show("Invalid Login Attempt\nPlease
> Contact
> | you're System Administrator", "Data Error", MessageBoxButtons.OK,
> | MessageBoxIcon.Error);
> | Application.Exit();
> | }
> | }
> | }
> |
> | Thank you very much for you're continued input, I'll buy you a beer or 2
> if
> | we ever get that conference together in Thailand .......
> |
> | Jamie
> |
> | "William Stacey [MVP]" <william.stacey@gmail.com> wrote in message
> | news:%23w7nd1rXGHA.4324@TK2MSFTNGP03.phx.gbl...
> | > Without seeing any code, maybe a sleep(50) before the thread starts
> the
> | > loop
> | > to give the dialog a chance to display.
> | >
> | > --
> | > William Stacey [MVP]
> | >
> | > "Jamie Bissett" <jameibissett@yahoo.com> wrote in message
> | > news:eYKzZtrXGHA.3724@TK2MSFTNGP02.phx.gbl...
> | > |I already Suspend the Updates on the UI adn Suspend Layout. I cannot
> move
> | > | this thread start to after the dialog display as it is a ShowDailog,
> | > which
> | > | means the thread will not start until the user has been validated,
> which
> | > | takes away the whole point of running this update on another thread.
> | > |
> | > | Jamie
> | > | "William Stacey [MVP]" <william.stacey@gmail.com> wrote in message
> | > | news:ORysZNrXGHA.508@TK2MSFTNGP02.phx.gbl...
> | > | > Maybe wait to start the thread after your dialog is displayed.
> | > Sounds
> | > | > like
> | > | > maybe the thread is doing much work and not allowing UI events.
> Also
> | > | > Suspend updates while building the UI on the hidden form and
> Resume
> | > | > updates
> | > | > on the control after updates are done.
> | > | >
> | > | > --
> | > | > William Stacey [MVP]
> | > | >
> | > | > "Jamie Bissett" <jameibissett@yahoo.com> wrote in message
> | > | > news:eyVRYDrXGHA.2376@TK2MSFTNGP03.phx.gbl...
> | > | > | Thanks for the info William,
> | > | > | I have implemented this model and yes it does work, but it is
> | > causing
> | > | > me
> | > | > a
> | > | > | little visual problem.
> | > | > |
> | > | > | What I do at startup is start the other thread as described in
> the
> | > model
> | > | > you
> | > | > | provided me, I hide the main form (which has the treeviews on
> it)
> | > and
> | > | > diaply
> | > | > | a login dialog.
> | > | > | What is happening now is that it see,s to delay the the painting
> o
> f
> | > the
> | > | > | login dialog i.e. the borders draw with a plain white background
> in
> | > the
> | > | > | dilaog then about 2 secs later the dilaog fills.
> | > | > |
> | > | > | Any ideas?
> | > | > |
> | > | > | Jamie
> | > | > | "Jamie Bissett" <jameibissett@yahoo.com> wrote in message
> | > | > | news:uUsZ7hqXGHA.4212@TK2MSFTNGP02.phx.gbl...
> | > | > | >I have an application that creates a pretty intensive TreeView
> at
> | > | > startup
> | > | > | >time. I had the program running on a single thread sucessfully,
> but
> | > the
> | > | > | >startup time was a bit excessive. When the application starts
> up
> it
> | > is
> | > | > a
> | > | > | >requirement for the user to log on, so in my magical wisdom, I
> | > thought
> | > | > | >shove all this processing on another thread, so it loads while
> the
> | > user
> | > | > | >logs on. I have all the code running on the thread OK, but I
> cannot
> | > | > figure
> | > | > | >out how to return the data to the main thread so that I can
> update
> | > the
> | > | > UI
> | > | > | >from the main thread.
> | > | > | >
> | > | > | > In the BackgroundWorker task I have created a new TreeView
> that
> is
> | > not
> | > | > | > attached to any UI. I build this in the background, I then
> | > attempted
> | > | > to
> | > | > | > Pass this back through an MSMQ Queue, but unfortunately the
> | > TreeView
> | > | > class
> | > | > | > in non Serializable so the Queue.Send fails.
> | > | > | >
> | > | > | > Can someone please explain to the best way to return this data
> to
> | > the
> | > | > main
> | > | > | > thread.
> | > | > | >
> | > | > | > Thanks in advance
> | > | > | >
> | > | > | > Jamie
> | > | > | >
> | > | > |
> | > | > |
> | > | >
> | > | >
> | > |
> | > |
> | >
> | >
> |
> |
>
>[/color]
