A: SwitchGlass does not appear in the Dock. Its interface is exposed through an icon on the right side of the menu bar at the top of the screen. (See screenshot above.)

A: Choose “Preferences…” from the SwitchGlass menu bar icon to open a window on each attached display. The appearance settings in each preferences window apply only to the app switcher on that display. The “Global Settings” at the bottom of the preferences window apply to SwitchGlass as a whole.

Note: when one preferences window is closed, all the preferences windows will close.

A: The “App Click” and “Shift-Click” pop-up menus in the preferences window are used to choose what will happen when you click or Shift-click an app icon in the app switcher. Every choice will activate the clicked app, but the actions all do something slightly different to the app’s windows. Here’s what each action does:

• Show All Windows - Activate an app and bring all its window to the front.
• Activate - Activate an app and bring only the “main and key windows” to the front. In practice, the “main” window is usually also the “key” window, so only one window will come to the front.
• Reopen - Activate an app in a way that triggers its “reopen” handler. Apps can choose to do whatever they want in response to a “reopen” action, but most bring a single window to the front, opening a new window (or un-minimizing a window from the Dock) if none are open. Note that some apps (e.g., Steam) cannot be reopened due to sandboxing restrictions. In these cases, the app is activated instead.
• Reopen and Show All - This is the same as “Reopen” except that SwitchGlass will also bring all the app’s windows to the front after sending the “reopen” action. Note that since apps can do whatever they want in response to a “reopen” action, some apps (e.g., Chrome) already bring all their windows to the front when reopened. For apps like that, the “Reopen” and “Reopen and Show All” actions are equivalent.

A: The “Show Apps” pop-up menu in the preferences window controls which apps appear in which app switchers. The options are:

• All - Show all eligible apps in all app switchers. This is the default.
• Filtered By Display - Show only apps that have open windows on the same display as the app switcher.

A: The “Visibility” pop-up menu in the preferences window controls the app switcher visibility on a specific display. The options are:

• Show - The app switcher is visible.
• Hide - The app switcher is not visible.
• Auto-Hide - The app switcher is not visible until the mouse cursor touches the region of the screen edge where is is positioned.

Hold down the Option key while clicking the SwitchGlass menu bar icon to temporarily toggle the visibility of any app switchers that have their visibility set to “Show” in preferences. This is meant as a shortcut to quickly hide and show visible app switchers. These changes are not persistent and are not reflected in the preferences windows. Only the visibility changes made directly in the preferences windows are persistent across launches.

A: You bet it does! Front and Center’s default “Classic” mode matches up perfectly with SwitchGlass’s default settings: click to bring all app windows to the front, shift-click to bring a single window to the front. You can also configure SwitchGlass to match Front and Center’s “Modern” mode by changing the click and Shift-click actions in the SwitchGlass preferences. And if you want to configure SwitchGlass and Front and Center differently, no problem, the two apps will communicate to ensure that they don’t interfere with each other’s actions.

A: The macOS Dock does show an icon for each running application and allows apps to be brought to the front and hidden. But the Dock also may contain other things: files, folders, recent (but not currently running) apps, plus the trash can. The Dock is also centered on the edge of the screen and has limited appearance options. It cannot appear in different positions and sizes on different displays, and it always brings all windows from an app to the front when an app icon is clicked.

SwitchGlass is for people who want an interface element dedicated entirely to application switching, with a customizable appearance and location for each attached display. When used alongside the Dock, SwitchGlass provides a second target for mouse-based app switching. With the Dock hidden, it provides an app-switching interface without any clutter from the other functions of the Dock.

A: You certainly could, but sometimes some people like to use the mouse (or trackpad) to switch apps.

A: SwitchGlass uses SwiftUI, Apple’s new user interface framework. SwiftUI runs only on macOS 10.15 Catalina or later.

Apple provides APIs to activate applications, optionally also bringing all of their windows to the front. Sometimes, when a call is made to one of these APIs, nothing happens. Or sometimes the app activates but none of its windows come to the front, even though the API call asked for all windows to come to the front. These bugs have existed in macOS for many years, and I’ve not yet found a workaround for them in SwitchGlass.

When this happens, quitting and relaunching the application that refused to come to the front will sometimes fix the problem. Other times, logging out and back in will do it. In extreme cases, a full restart may be required. For some applications, even these solutions don’t work. (Microsoft Outlook, in particular, seems completely immune to all window layering API calls available to third-party apps.)

This bug has been filed with Apple as FB7603765.

SwitchGlass is intentionally hidden on any display that contains a window in full-screen mode. The rationale is that full-screen mode is a way to assert ownership of the entire display. Drawing another app on top of a full-screen app violates this expectation.

If you would like to access an app switcher on a display that contains a window in full-screen mode, set the app switcher’s visibility to Auto-Hide.

As far as I am aware, there are no public APIs in macOS that allow third-party apps to implement these features in the same way that the Dock does.

Some applications change their Dock icons while running. For example, Apple’s Calendar app changes its Dock icon to show the current date. As far as I am aware, there are no public APIs in macOS that allow third-party apps to show these icons. The dynamic icon updates are communicated to and accessible by the Dock only.

Sandboxed Mac apps cannot tell arbitrary other applications to quit.

It is possible to include an explicit list of apps that can be terminated, but the list must be compiled into SwitchGlass itself and cannot change. It’s not possible to know every application that every user might run, so this feature is not feasible for SwitchGlass.

Not all apps can understand all file formats. SwitchGlass only allows drag-and-drop when it has determined that an app can handle the files being dropped onto it. If you have a situation where you think an app should accept a dropped file but SwitchGlass is disallowing it, please contact us.

A: The icon padding slider in the SwitchGlass preferences window controls the padding between icons in the app switcher as a percentage of the icon size, from 0% to 100%. For example, if the icon size is set to 32 points and the padding slider is at 50%, then then each icon will have 16 points of padding around it.

The text field to the right of the icon padding slider shows the slider’s exact value. It exists to allow fine-tuning without having to carefully move the slider a tiny amount.

Changing the icon size does not change the position of the icon padding slider (or the text field that reflects its value). If set to 50%, it will remain at 50% no matter how the icon size changes.

The icon padding “Size” text field below the icon padding slider exists to allow the padding to be set directly, rather than as a percentage of the icon size. As the icon size changes, the computed padding size will also change. For example, with the icon padding slider set to 50%, if the icon size changes from 32 points to 48 points, the padding size text field will change from 16 points to 24 points.

The “switch” part is easy: SwitchGlass is used to switch apps. I had considered “Switchblade,” but rejected it as too violent. For whatever reason, my mind jumped from there to switchgrass, the plant. Then it was just a short hop to SwitchGlass based on the app switcher’s translucent, glass-like appearance. The name is InterCapped in the tradition of classic Mac applications like MacPaint, MacWrite, FileMaker, SuperPaint, etc.

The SwitchGlass icon was created by Brad Ellis.

Here are a few:

• Hold down the Option key while clicking the menu bar icon to quickly hide and show all visible app switchers. (Read more above.)
• Hold down the Option key while clicking the “Reset” button in the preferences window to reset more settings to their default values.
• When auto-hide is enabled, holding down the Option key will prevent the app switcher from appearing when the pointer enters its activation area.
• Command-Option-click the menu bar icon to cycle through the different menu bar icons.
• Command-Option-Shift-click the menu bar icon to switch the API set used to activate apps. (Sadly, both available API sets exhibit the same bugs described above.)

Yes.