Table of Contents

Floating Windows

Dock can detach dockables into separate floating windows. These windows are represented by the IDockWindow interface and hosted using IHostWindow implementations.

Creating windows

FactoryBase exposes a CreateWindowFrom method which returns an IDockWindow. Override this method on your factory to customize the dock window that represents a floating layout:

public override IDockWindow? CreateWindowFrom(IDockable dockable)
{
    var window = base.CreateWindowFrom(dockable);
    if (window is null)
    {
        return null;
    }

    window.Title = $"Dock - {dockable.Title}";
    return window;
}

Calling FloatDockable on the factory opens a dockable in a new window. The new IDockWindow is tracked by the root dock and stores its bounds and title so it can be serialized together with the layout.

To customize the platform window (IHostWindow) used by floating docks, use HostWindowLocator or DefaultHostWindowLocator. See Host window locators for details.

Managed windows

When DockSettings.UseManagedWindows is enabled, floating windows are hosted inside the main window instead of spawning native OS windows. The default host window becomes ManagedHostWindow, which renders floating windows inside ManagedWindowLayer using the MDI layout system.

If you override host window creation, return ManagedHostWindow when managed windows are enabled. DockControl.EnableManagedWindowLayer must remain true for managed windows to appear.

For setup details see the Managed windows guide and Managed windows how-to.

IDockWindow model members

IDockWindow represents the floating window model and includes:

Member Type Description
Id string Window identifier.
X, Y double Window position.
Width, Height double Window size.
Topmost bool Keeps the window on top when true.
Title string Window title.
Owner IDockable? Dockable that owns the window.
Factory IFactory? Factory used by the window.
Layout IRootDock? Root layout hosted in the window.
Host IHostWindow? Platform host window.
OnClose() bool Close callback (return false to cancel).
OnMoveDragBegin() bool Drag begin callback (return false to cancel).
OnMoveDrag() void Drag in progress callback.
OnMoveDragEnd() void Drag end callback.
Save() void Persist size/position into the model.
Present(bool) void Show the window.
Exit() void Close the window.
SetActive() void Activate the window.

IHostWindow members

IHostWindow is the platform-facing host. It provides:

Member Type Description
HostWindowState IHostWindowState? Docking state for the host.
IsTracked bool Whether size/position is tracked.
Window IDockWindow? Backing dock window model.
Present(bool) void Show the host window.
Exit() void Close the host window.
SetPosition/GetPosition void Read/write the host position.
SetSize/GetSize void Read/write the host size.
SetTitle void Update the host title.
SetLayout void Assign the hosted layout.
SetActive void Activate the host window.

Window chrome options

HostWindow provides two boolean properties that control how its chrome behaves:

  • ToolChromeControlsWholeWindow
  • DocumentChromeControlsWholeWindow

When enabled these toggle the :toolchromecontrolswindow or :documentchromecontrolswindow pseudo class respectively. Styles can use these states to remove the standard system chrome and let the Dock chrome occupy the entire window.

Presenting and closing

IDockWindow exposes Present(bool isDialog) to show the window and Exit() to close it programmatically. The default implementation uses HostAdapter to bridge between the interface and the underlying Avalonia Window.

Use the WindowOpened and WindowClosed events on the factory to track when floating windows appear or disappear.

factory.WindowClosed += (_, e) =>
    Console.WriteLine($"Closed {e.Window?.Title}");

Window magnetism

Floating windows can optionally snap to the edges of other floating windows while being dragged. This behavior is controlled by two settings on DockSettings:

  • EnableWindowMagnetism enables or disables the feature.
  • WindowMagnetDistance specifies how close windows must be before they snap together.

When magnetism is enabled, HostWindow compares its position against other tracked windows during a drag and adjusts the position if it falls within the snap distance. This makes it easy to align multiple floating windows. In managed mode, the same logic applies to managed floating windows within the managed layer.

Bringing windows to front

If DockSettings.BringWindowsToFrontOnDrag is enabled, initiating a drag will activate all floating windows and any main window hosting a DockControl so they stay above other applications until the drag completes. In managed mode, this updates managed z-order so windows stay above their peers.

For more advanced scenarios see Adapter Classes and the Advanced Guide.

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