apple-dev-mcp/content/platforms/macos/windows.md

Complete Apple development guidance: Human Interface Guidelines (design) + Technical Documentation for iOS, macOS, watchOS, tvOS, and visionOS

---
title: Windows
platform: macOS
category: foundations
url: https://developer.apple.com/design/human-interface-guidelines/windows
quality_score: 0.49
content_length: 14309
last_updated: 2025-07-20T03:47:11.308Z
keywords: ["windows","macos","foundations","visual","system","interface","controls","navigation","layout","gestures","buttons","input","color","status"]
has_code_examples: false
has_images: false
is_fallback: false
---

June 9, 2025 Added best practices, and updated with guidance for resizable windows in i Pad OS. Windows A window presents UI views and components in your app or game. In i Pad OS, mac OS, and vision OS, windows help define the visual boundaries of app content and separate it from other areas of the system, and enable multitasking workflows both within and between apps. Windows include system-provided interface elements such as frames and window controls that let people open, close, resize, and relocate them. Conceptually, apps use two types of windows to display content:A primary window presents the main navigation and content of an app, and actions associated with them. An auxiliary window presents a specific task or area in an app. Dedicated to one experience, an auxiliary window doesn’t allow navigation to other app areas, and it typically includes a button people use to close it after completing the task. For guidance laying out content within a window on any platform, see Layout; for guidance laying out content in Apple Vision Pro space, see Spatial layout. For developer guidance, see Windows. Best practices Make sure that your windows adapt fluidly to different sizes to support multitasking and multiwindow workflows. For guidance, see Layout and Multitasking. Choose the right moment to open a new window. Opening content in a separate window is great for helping people multitask or preserve context. For example, Mail opens a new window whenever someone selects the Compose action, so both the new message and the existing email are visible at the same time. However, opening new windows excessively creates clutter and can make navigating your app more confusing. Avoid opening new windows as default behavior unless it makes sense for your app. Consider providing the option to view content in a new window. While it’s best to avoid opening new windows as default behavior unless it benefits your user experience, it’s also great to give people the flexibility of viewing content in multiple ways. Consider letting people view content in a new window using a command in a context menu or in the File menu. For developer guidance, see Open Window Action. Avoid creating custom window UI. System-provided windows look and behave in a way that people understand and recognize. Avoid making custom window frames or controls, and don’t try to replicate the system-provided appearance. Doing so without perfectly matching the system’s look and behavior can make your app feel broken. Use the term window in user-facing content. The system refers to app windows as windows regardless of type. Using different terms — including scene, which refers to window implementation — is likely to confuse people. Platform considerations Not supported in i OS, tv OS, or watch OS.i Pad OSWindows present in one of two ways depending on a person’s choice in Multitasking & Gestures settings. Full screen. App windows fill the entire screen, and people switch between them — or between multiple windows of the same app — using the app switcher. Windowed. People can freely resize app windows. Multiple windows can be onscreen at once, and people can reposition them and bring them to the front. The system remembers window size and placement even when an app is closed. Make sure window controls don’t overlap toolbar items. When windowed, app windows include window controls at the leading edge of the toolbar. If your app has toolbar buttons at the leading edge, they might be hidden by window controls when they appear. To prevent this, instead of placing buttons directly on the leading edge, move them inward when the window controls appear. Consider letting people use a gesture to open content in a new window. For example, people can use the pinch gesture to expand a Notes item into a new window. For developer guidance, see collection View(\_:scene Activation Configuration For Item At:point:) (to transition from a collection view item), or UIWindow Scene. Activation Interaction (to transition from an item in any other view).Tip If you only need to let people view one file, you can present it without creating your own window, but you must support multiple windows in your app. For developer guidance, see QLPreview Scene Activation Configuration.mac OSIn mac OS, people typically run several apps at the same time, often viewing windows from multiple apps on one desktop and switching frequently between different windows — moving, resizing, minimizing, and revealing the windows to suit their work style. To learn about setting up a window to display your game in mac OS, see Managing your game window for Metal in mac OS.mac OS window anatomy A mac OS window consists of a frame and a body area. People can move a window by dragging the frame and can often resize the window by dragging its edges. The frame of a window appears above the body area and can include window controls and a toolbar. In rare cases, a window can also display a bottom bar, which is a part of the frame that appears below body content.mac OS window states A mac OS window can have one of three states:Main. The frontmost window that people view is an app’s main window. There can be only one main window per app. Key. Also called the active window, the key window accepts people’s input. There can be only one key window onscreen at a time. Although the front app’s main window is usually the key window, another window — such as a panel floating above the main window — might be key instead. People typically click a window to make it key; when people click an app’s Dock icon to bring all of that app’s windows forward, only the most recently accessed window becomes key. Inactive. A window that’s not in the foreground is an inactive window. The system gives main, key, and inactive windows different appearances to help people visually identify them. For example, the key window uses color in the title bar options for closing, minimizing, and zooming; inactive windows and main windows that aren’t key use gray in these options. Also, inactive windows don’t use vibrancy (an effect that can pull color into a window from the content underneath it), which makes them appear subdued and seem visually farther away than the main and key windows. Note Some windows — typically, panels like Colors or Fonts — become the key window only when people click the window’s title bar or a component that requires keyboard input, such as a text field. Make sure custom windows use the system-defined appearances. People rely on the visual differences between windows to help them identify the foreground window and know which window will accept their input. When you use system-provided components, a window’s background and button appearances update automatically when the window changes state; if you use custom implementations, you need to do this work yourself. Avoid putting critical information or actions in a bottom bar, because people often relocate a window in a way that hides its bottom edge. If you must include one, use it only to display a small amount of information directly related to a window’s contents or to a selected item within it. For example, Finder uses a bottom bar (called the status bar) to display the total number of items in a window, the number of selected items, and how much space is available on the disk. A bottom bar is small, so if you have more information to display, consider using an inspector, which typically presents information on the trailing side of a split view.vision OSvision OS defines two main window styles: default and volumetric. Both a default window (called a window) and a volumetric window (called a volume) can display 2 D and 3 D content, and people can view multiple windows and volumes at the same time in both the Shared Space and a Full Space. A window A volume Notevision OS also defines the plain window style, which is similar to the default style, except that the upright plane doesn’t use the glass background. For developer guidance, see Plain Window Style. The system defines the initial position of the first window or volume people open in your app or game. In both the Shared Space and a Full Space, people can move windows and volumes to new locations.vision OS windows The default window style consists of an upright plane that uses an unmodifiable background material called glass and includes a close button, window bar, and resize controls that let people close, move, and resize the window. A window can also include a Share button, tab bar, toolbar, and one or more ornaments. By default, vision OS uses dynamic scale to help a window’s size appear to remain consistent regardless of its proximity to the viewer. For developer guidance, see Default Window Style. A window Prefer using a window to present a familiar interface and to support familiar tasks. Help people feel at home in your app by displaying an interface they’re already comfortable with, reserving more immersive experiences for the meaningful content and activities you offer. If you want to showcase bounded 3 D content like a game board, consider using a volume. Retain the window’s glass background. The default glass background helps your content feel like part of people’s surroundings while adapting dynamically to lighting and using specular reflections and shadows to communicate the window’s scale and position. Removing the glass material tends to cause UI elements and text to become less legible and to no longer appear related to each other; using an opaque background obscures people’s surroundings and can make a window feel constricting and heavy. Choose an initial window size that minimizes empty areas within it. By default, a window measures 1280 x 720 pt. When a window first opens, the system places it about two meters in front of the wearer, giving it an apparent width of about three meters. Too much empty space inside a window can make it look unnecessarily large while also obscuring other content in people’s space. Aim for an initial shape that suits a window’s content. For example, a default Keynote window is wide because slides are wide, whereas a default Safari window is tall because most webpages are much longer than they are wide. For games, a tower-building game is likely to open in a taller window than a driving game. Choose a minimum and maximum size for each window to help keep your content looking great. People appreciate being able to resize windows as they customize their space, but you need to make sure your layout adjusts well across all sizes. If you don’t set a minimum and maximum size for a window, people could make it so small that UI elements overlap or so large that your app or game becomes unusable. For developer guidance, see Positioning and sizing windows. A window containing 3 D content Minimize the depth of 3 D content you display in a window. The system adds highlights and shadows to the views and controls within a window, giving them the appearance of depth and helping them feel more substantial, especially when people view the window from an angle. Although you can display 3 D content in a window, the system clips it if the content extends too far from the window’s surface. To display 3 D content that has greater depth, use a volume.vision OS volumes You can use a volume to display 2 D or 3 D content that people can view from any angle. A volume includes window-management controls just like a window, but unlike in a window, a volume’s close button and window bar shift position to face the viewer as they move around the volume. For developer guidance, see Volumetric Window Style. A volume Prefer using a volume to display rich, 3 D content. In contrast, if you want to present a familiar, UI-centric interface, it generally works best to use a window. Place 2 D content so it looks good from multiple angles. Because a person’s perspective changes as they move around a volume, the location of 2 D content within it might appear to change in ways that don’t make sense. To pin 2 D content to specific areas of 3 D content inside a volume, you can use an attachment. In general, use dynamic scaling. Dynamic scaling helps a volume’s content remain comfortably legible and easy to interact with, even when it’s far away from the viewer. On the other hand, if you want a volume’s content to represent a real-world object, like a product in a retail app, you can use fixed scaling (this is the default).Take advantage of the default baseplate appearance to help people discern the edges of a volume. In vision OS 2 and later, the system automatically makes a volume’s horizontal “floor,” or baseplate, visible by displaying a gentle glow around its border when people look at it. If your content doesn’t fill the volume, the system-provided glow can help people become aware of the volume’s edges, which can be particularly useful in keeping the resize control easy to find. On the other hand, if your content is full bleed or fills the volume’s bounds — or if you display a custom baseplate appearance — you may not want the default glow. Consider offering high-value content in an ornament. In vision OS 2 and later, a volume can include an ornament in addition to a toolbar and tab bar. You can use an ornament to reduce clutter in a volume and elevate important views or controls. When you use an attachment anchor to specify the ornament’s location, such as top Back or bottom Front, the ornament remains in the same position, relative to the viewer’s perspective, as they move around the volume. Be sure to avoid placing an ornament on the same edge as a toolbar or tab bar, and prefer creating only one additional ornament to avoid overshadowing the important content in your volume. For developer guidance, see ornament(visibility:attachment Anchor:content Alignment:ornament:).Choose an alignment that supports the way people interact with your volume. As people move a volume, the baseplate can remain parallel to the floor of a person’s surroundings, or it can tilt to match the angle at which a person is looking. In general, a volume that remains parallel to the floor works well for content that people don’t interact with much, whereas a volume that tilts to match where a person is looking can keep content comfortably usable, even when the viewer is reclining.