How to populate TreeView with BackgroundWorker

See more:

C#

treeview

BackgroundWorker

Hi,

I have a method that populates a treeview. I call this method from a listview with MouseDoubleClick. This method does all the job: reads the SQL table, generates 3 List<> (parent, child, grandchild) and some if... and foreach... loops builds the treeview from these lists' elements. Works fine.

But! It is quite slow... I would like to use BackgroundWorker with showing up some 'loading circle' gif with the property of visible of that PictureBox.

How can I run this method within a DoWork event?

I have this DoWork event, but it is not corrent:

private void loading_DoWork(object sender, DoWorkEventArgs e)
        {

            if (loading.CancellationPending == true)
            {
                loadingPicBox.Visible = false;
                e.Cancel = true;
            }
            else
            {
                if(loadingPicBox.InvokeRequired)
                {
                    loadingPicBox.Invoke((MethodInvoker)delegate () { loadingPicBox.Visible = true; });
                    Thread.Sleep(100);//if this is not here, I cannot see the gif...
                }
                if (dokuSiteListView.InvokeRequired)
                {
                    dokuSiteListView.Invoke((MethodInvoker)delegate () { BuildTree(); });
                }
            }

        }

private void dokuSiteListView_MouseDoubleClick(object sender, MouseEventArgs e)
        {
            if (!loading.IsBusy)
            {
                loading.RunWorkerAsync();
            }
        }

As you can see, if I doubleclick on an item in dokuSiteListView, I call loading.RunWorkerAsync();, the loadingPicBox become visible, and building tree is starting. But the gif animation stops as the tree building start...

Can somebody please give me the right code to call my BuildTree() method from a backgroundworker?