window_toolbox #

window_toolbox is a Flutter package for building custom window chrome compatible with Flutter's multi-window API. Special care has been taken to ensure that expected platform behavior, such snap layout on Windows, is preserved, while still allowing for a high degree of customization.

In addition to custom window chrome, this package also provides extension classes on top of native window controllers, exposing more native window functionality and allowing to react to subset of NSWindowDelegate methods or handing win32 messages directly in Dart.

Custom window chrome #

To customize window, it is necessary first to start with disabling existing window decorations:

controller = RegularWindowController(...);
controller.enableCustomWindow();

Once that is done, you can place various widgets in your widget tree to build draggable areas, traffic light buttons (macOS) or window buttons:

• WindowDragArea - Widget that creates area that can be used to drag the window.
• WindowDragExcludeArea - Marks places inside WindowDragArea that should not be draggable. This is useful for buttons in title bar, tabs, or other controls that should not participate in window dragging.
• WindowTrafficLight - a "proxy" widget for macOS traffic light. Wherever this widget is placed, the actual macOS traffic light buttons will be positioned. This widget can also be used to hide the traffic light buttons completely.
• MaximizeButton, MinimizeButton, CloseButton - Widgets representing standard window buttons. These accept custom builders so the presentation is fully customizable, while ensuring the proper behavior on each platform. On Windows the MaximizeButton properly supports the snap layout popup.
• WindowBorder - On Linux draws shadows, border and clips the content to round corners (if specified). On other platforms this widget has no effect, since shadows, borders and clipping are handled by the system compositor.

A complete example of fully customized window can be found in the example directory.

Additional window functionality #

On top of custom window chrome, window_toolbox also provides some additional platform specific functionality related to native windows.

This includes:

• Exposing more of NSWindow API and ability to register custom delegate for macOS windows. See WindowDelegateMacOS for more details.

• Ability to register custom delegate and message handlers on Windows. See Win32MessageHandler for more details.

• Ability to register custom delegate on linux. See WindowDelegateLinux for more details.

The windowing API surface is very big and exposing more of the platform specific functionality is planned, requests and contributions are welcome.