Windows

Because UI Toolkit lacks a z-index property and the visual order is determined by the order in the hierarchy, we have to get creative when we want elements to be rendered on top of everything. Windows are one such situation.

Context

A WindowsContext ancestor is necessary for Windows to work. It handles windows positioning and order.

Props

• bool forceFit: If true, windows will be forced to fully stay inside the content rect of the WindowContext.
• int safeZoneSize: The safe zone size in pixels. If forceFit is false, windows will be forced to never leave the safe zone.
• bool hideAllWindows: If true, all windows are hidden (even if they’re open).
• VisualAttributes visualAttributes: Styling information. Expanded in Create method.
• Children children: Children.

Window

The Window element actually returns nothing in its Render method: protected override Element Render() => Element.Null;. Instead it communicates with a WindowsContext ancestor and the context will add content as one of its children.

Props

• ulong? guid: If provided, it must be unique and it allows WindowsContext to identify the Window even after hierarchy changes. It is recommended to always set it.
• bool open: Whether or not the window is open.
• bool draggable: Whether or not the window can be dragged.
• Element content: The content that WindowsContext will add when the window is open.
• bool alwaysOnTop: Whether or not the window should always be on top of all the others.
• Vector2? offset: Offset relative to the top left corner of the WindowsContext content rect. If set, the default dragging system will be skipped and this offset will always be used.
• Action<WindowDragData> onDrag: Callback that gets called when the window is dragged.

Dragging

A Window comunicates and passes upwards a content to a WindowsContext. It’s not listening to input events, it’s not rendering anything, it’s just a logical “ghost” element.

To allow Windows to be dragged, you need to set draggable to true and content must have a WindowHeader child. The WindowHeader will listen to input events and communicate with the WindowsContext.