ThemeSelector
A ThemeSelector is a DropdownField of the themes in Workspace.AvailableThemes. A pick calls SetTheme on the workspace that contains the selector, on the workspace named by workspace, or on Workspace. The selector follows Workspace.ThemeChanged, so a SetTheme from other code shows too.
The selector shows "High contrast" for high-contrast, and dark for default.
<!-- Inside a workspace: the selector themes that workspace -->
<tb:ThemeSelector />
<!-- Outside it: name the workspace -->
<tb:ThemeSelector workspace="workspace" />
In code, set Workspace. The selector reads the theme when it attaches and when you set Workspace, and follows ThemeChanged while it is attached, so a SetTheme call from other code shows too. The class is tb-theme-selector. The WorkspaceDemo example has a selector in its top bar, and the Settings screen of the GameMenu example and the theme command of the debug console in the CodeDemo example use AvailableThemes.