Make the Root window a permanent dock target

[KouniakiosKatakthths]

How can i make the root window to be a dock target for all the dockable tools and documents that are created?
Kinda like how Visual Studio window can be used to dock tools even when there are no windows dock to it.

[nikmanderss]

@KouniakiosKatakthths Did you ever figure this out on your own?

[nikmanderss]

The behavior I’m struggling with:

• I can create a root layout with tool docks.
• I can float the tool windows.
• Once all tools are floated out, the main workspace seems to stop being a useful dock target.
• I can dock the floating tool windows into each other, but I cannot reliably dock them back into the main workspace.

I’m aiming for something closer to Visual Studio:

• You can close/float all tool windows.
• The main IDE surface still exists.
• Opening/floating Solution Explorer, Output, etc. still allows docking back into the main IDE window.
• Documents may exist later, but I do not want to require a fake document dock just to keep the main dock workspace alive?

I've went through numerous samples in the repo and I can't seem to find an example of just declaring a permanent root dock as a target...

Any guidance would be appreciated.

[nikmanderss]

Update after testing with RootDockDebug.

For context, I’m using the MVVM/factory approach, not defining the dock layout directly in XAML.

The layout is created in my custom Factory.CreateLayout() override, then initialized with Factory.InitLayout(layout), and the view hosts it with a DockControl bound to the root layout.

I changed the layout to a tool-only proportional layout:

RootDock
  MainDock / IProportionalDock
    Stream ToolDockA
      Stream
    IProportionalDockSplitter
    Signals ToolDockB
      Signals

This gives me the initial layout I want:

Stream | Signals

with a draggable splitter between the tools and no DocumentDock.

The remaining issue is now more specific.

Steps:

1. Float Signals.
2. Drag/dock Signals back into the main root window on the right side.
3. The redock appears to succeed visually.
4. RootDockDebug then shows something like:

IProportionalDock
  MainDock
    Stream ToolDockA
      Stream
    IProportionalDockSplitter
    IToolDock
      Signals ToolDockB

So Signals ToolB does get inserted back into the main layout.

However, the old floating host window remains open as an empty black window. It no longer appears to contain Signal ToolB, but the floating window itself is still visible and cannot really be interacted with.

So the problem may not be that the main root is unavailable as a dock target. The redock seems to succeed. The problem appears to be that the old floating HostWindow / temporary IToolDock does not close after its last dockable is moved back into the main layout.

I also tested both host window modes.

With:

HostWindowLocator = new Dictionary<string, Func<IHostWindow?>>
{
    [nameof(IDockWindow)] = () => new HostWindow()
};

the floating window exists and the tool can be redocked, but the empty host window remains afterward.

With:

HostWindowLocator = new Dictionary<string, Func<IHostWindow?>>
{
    [nameof(IDockWindow)] = () => new ManagedHostWindow()
};

dragging the tool out causes it to disappear/remove entirely in my app, so HostWindow seems closer to the intended behavior?

I’m trying to understand if I’m missing a required setting, factory setup, DockControl option, or cleanup call that closes the floating host window when its last dockable is moved back into the main layout.

In short: redocking appears to work, but cleanup of the emptied floating host window does not.

Startuo:

After dragging Signals TookDockB back onto right-hand side of main:

Video:

2026-07-14.09-55-16.mp4