Hiya.

I am shamelessly trying to copy "someone's" idea of a MainForm.

My intention is to get rid of the MenuStrip and use the ThemedToolStrip instead. So far, so good. But now I got to the "Window" item, which will show the opened MDI windows list.

Now I would need to have a "Window" ToolStripDropDownButton to behave in the same way as the MenuStrip MdiWindowListItem. Would that be too difficult to implement?

Cheers.

The form handle won't change after it has been assigned.  If you are running in an MDI environment, then you can handle the OnParentChanged event and save off the handle at that point (I recommend against this).  You should ALWAYS be able to reference the Me.Handle of the form and it will return the handle to which it is presently assigned, which is the only one that you should ever deal with.  This is standard WinForms logic...once a handle is assigned it should never be changed unless the parent changes...that may be the ONLY time that it would change. 

Now it is another thing entirely if the handle has already been released.  In that case you just need to handle an event further up the chain to perform your closing logic.

Just to confirm,

I'm also getting back a different handle to than which the child window was assigned on creation.

And also I've tried changing to formclosing but the handle still changes.

Edhy Rijo

OK...different than what?  You have mentioned that you are getting back a different handle...but what are you comparing the handle to? 

Oh....nevermind, you are using that older logic on the window handles being stored off in the collection...gotcha.  I will see if I can reproduce.

Since we no longer use this logic I hadn't noticed that Vista changes the handle several times through the life of the form.  So to get around this, if you still intend to use window handle, then you will need to override the OnHandleChanged method to trap that event so that you can update your collection logic.

However, I would recommend against using the window handle at this point and add a Guid property to your BaseForm that uniquely identifies the form:

Then you can enumerate the Forms collection of the MDI to find your form and then activate it (this code would be referencing the MDI  form):

If you take this approach you will be much safer across multiple platforms and won't be reliant upon the window handle.

Trent, I hate to ask, but using the GUID logic, where is the MyLookupID value coming from?

Edhy Rijo

You would be passing it into some method.  If you look further up the food-chain on this thread, you will see that they have a collection that stores off the open forms.  So when the form is loaded, you would add this guid to the collection with probably a title or something else so that it could be identified in the list (if you are using the panel on the left approach).