NetOffice - Custom Task Pane in a Appointment window in Outlook

Question

I found out that it's possible to add custom task panes to individual windows like e.g. the appointment with this code snippet:

    public void Inspectors_NewInspector(Microsoft.Office.Interop.Outlook.Inspector Inspector)
{
    Microsoft.Office.Tools.CustomTaskPane myCustomTaskPane;

    if(Inspector.CurrentItem is  Microsoft.Office.Interop.Outlook.AppointmentItem ) {

        UserControl uc1 = MyUserControl();
        myCustomTaskPane = getAddIn().CustomTaskPanes.Add(uc1, "MyPanel",Inspector);
        myCustomTaskPane.DockPosition = Office.MsoCTPDockPosition.msoCTPDockPositionRight;
        myCustomTaskPane.DockPositionRestrict = Office.MsoCTPDockPositionRestrict.msoCTPDockPositionRestrictNoChange;
        myCustomTaskPane.Visible = true;

    }

    //Additionally You can add a property change listener to the current Item here
}

however, I use 'NetOffice' instead of VSTO to have the add-in compatible with various Outlook versions. And there the add-in doesn't have the CustomTaskPanes property, and the TaskPanes.Add property isn't overloaded to allow adding custom panes on other window than the main explorer.

Answer 1

Ok, worked it out in following way. In the ComAddin class I have a local variable

    Office._CustomTaskPane _taskPane;

and I set the variable on the overriden CTPFactoryAvailable method:

    public override void CTPFactoryAvailable(object CTPFactoryInst)
    {
            _ctpFactory = new NetOffice.OfficeApi.ICTPFactory(this.Application, CTPFactoryInst);
    }

Then - when the addin is loaded - I'm adding an event handler to the NewInspectorEvent event:

    private void Addin_OnStartupComplete(ref Array custom)
    {
        var inspectors = Application.Inspectors as NetOffice.OutlookApi.Inspectors;
        inspectors.NewInspectorEvent += Inspectors_NewInspectorEvent;
    }

In the event handler for creating a new inspector window, I'm creating the pane:

    private void Inspectors_NewInspectorEvent(_Inspector Inspector)
    {
        var ai = Inspector.CurrentItem as AppointmentItem;
        if (ai == null)
            return;
        var ins = Inspector as NetOffice.OutlookApi.Inspector;
        _taskPane = _ctpFactory.CreateCTP(typeof(Addin).Assembly.GetName().Name + ".UserControl1", "My title", Inspector);
        _taskPane.DockPosition = MsoCTPDockPosition.msoCTPDockPositionTop;
        _taskPane.Height = 50;
        _taskPane.Visible = true;
    }

This draft proof of concept works for me.