Toga Roadmap

Toga is a new project - we have lots of things that we’d like to do. If you’d like to contribute, providing a patch for one of these features.


The core of Toga is it’s widget set. Modern GUI apps have lots of native controls that need to be represented. The following widgets have no representation at present, and need to be added.

There’s also the task of porting widgets available on one platform to another platform.


Inputs are mechanisms for displaying and editing input provided by the user.

  • ComboBox - A free entry TextField that provides options (e.g., text with
    past choices) - Cocoa: NSComboBox - GTK+: Gtk.ComboBox.new_with_model_and_entry - iOS: ?
  • Switch - A native control for enabled/disabled
    • Cocoa: NSButton with checkbox style
    • GTK+: Gtk.CheckButton (maybe Gtk.Switch?)
    • iOS: UISwitch
  • DateInput - A widget for selecting a date
    • Cocoa: NSDatePicker, constrained to DMY
    • GTK+: Gtk.Calendar?
    • iOS: UIDatePicker
  • TimeInput - A widget for selecting a time
    • Cocoa: NSDatePicker, Constrained to Time
    • GTK+: ?
    • iOS: UIDatePicker
  • DateTimeInput - A widget for selecting a date and a time.
    • Cocoa: NSDatePicker
    • GTK+: Gtk.Calendar + ?
    • iOS: UIDatePicker
  • MultilineTextInput - A widget for displaying multiline text, optionally
    editable. - Cocoa: NSTextView inside an NSScrollView - GTK+: Gtk.TextView? (is there a simpler version than a full text editor?) - iOS: UITextView
  • Selection - A button that allows the user to choose from one of a fixed
    number of options - Cocoa: NSPopupButton, with NSMenu for options. - GTK+: Gtk.ComboBox.new_with_model - iOS: UIPickerView
  • ColorInput - A widget for selecting a color
    • Cocoa: NSColorWell
    • GTK+: Gtk.ColorButton
    • iOS: ?
  • SliderInput (H & V) - A widget for selecting a value from a range.
    • Cocoa: NSSlider
    • GTK+: Gtk.Scale
    • iOS: UISlider
  • NumberInput - A widget to allow entry of a numerical value, possibly with
    helper buttons to make it easy to increase/decrease the value. - Cocoa: NSTextField with NSStepper - GTK+: GTKSpinButton - iOS: UITextField with UIStepper
  • Table: A scrollable display of columns of tabular data
    • Cocoa: Done
    • GTK+: Gtk.TreeView with a Gtk.ListStore
    • iOS: UITableView
  • Tree: A scrollable display of heirarchical data
    • Cocoa: Done
    • GTK+: Gtk.TreeView with a Gtk.TreeStore
    • iOS: UITableView with navigation
  • DetailedList: A scrollable list of a single column of detailed data
    • Cocoa: NSTableView with custom view?
    • iOS: UITableView with navigation
  • SearchInput - A variant of TextField that is decorated as a search box.
    • Cocoa: NSSearchField
    • GTK+: ?
    • iOS: UISearchBar?


Views are mechanisms for displaying rich content, usually in a readonly manner.

  • Separator - a visual separator; usually a faint line.
    • Cocoa: NSSeparator
    • GTK+:
    • iOS:
  • ProgressBar - A horizontal bar that displays progress, either progress
    against a known value, or indeterminiate - Cocoa: NSProgressIndicator, Bar style - GTK+: Gtk.ProgressBar - iOS: UIProgressView
  • ActivityIndicator - A spinner widget showing that something is happening
    • Cocoa: NSProgressIndicator, Spinning style
    • GTK+: Gtk.Spinner
    • iOS: UIActivityIndicatorView
  • ImageView - Display an graphical image
    • Cocoa: NSImageView
    • GTK+: Gtk.Image
    • iOS: UIImageView
  • VideoView - Display a video
    • Cocoa: AVPlayerView
    • GTK+: Custom Integrate with GStreamer
    • iOS: MPMoviePlayerController
  • WebView - Display a web page. Just the web page; no URL chrome, etc.
    • Cocoa: WebView
    • GTK+: Webkit.WebView (via WebkitGtk)
    • iOS: UIWebView
  • PDFView - Display a PDF document
    • Cocoa: PDFView
    • GTK+: ?
    • iOS: ? Integration with QuickLook?
  • MapView - Display a map
    • Cocoa: MKMapView
    • GTK+: Probably a Webkit.WebView pointing at Google Maps/
    • iOS: MKMapView

Container widgets

Containers are widgets that can contain other widgets.

  • Box - A box drawn around a collection of widgets; often has a label
    • Cocoa: NSBox
    • GTK+:
    • iOS:
  • ButtonContainer - A layout for a group of radio/checkbox options
    • Cocoa: NSMatrix, or NSView with pre-set constraints.
    • GTK+: ListBox?
    • iOS:
  • ScrollContainer - A container whose internal content can be scrolled.
    • Cocoa: Done
    • GTK+:
    • iOS: UIScrollView?
  • SplitContainer - An adjustable separator bar between 2+ visible panes of content
    • Cocoa: Done
    • GTK+:
    • iOS:
  • FormContainer - A layout for a “key/value” or “label/widget” form
    • Cocoa: NSForm, or NSView with pre-set constraints.
    • GTK+:
    • iOS:
  • OptionContainer - (suggestions for better name welcome) A container view that
    holds a small, fixed number of subviews, only one of which is visible at any given time. Generally rendered as something with “lozenge” style buttons over a box. Examples of use: OS X System preference panes that contain multiple options (e.g., Keyboard settings have an option layout for “Keyboard”, “Text”, “Shortcuts” and “Input sources”) - Cocoa: NSTabView - GTK+: GtkNotebook (Maybe GtkStack on 3.10+?) - iOS: ?
  • SectionContainer - (suggestions for better name welcome) A container view that
    holds a small number of subviews, only one of which is visible at any given time. Each “section” has a name and icon. Examples of use: top level navigation in Safari’s preferences panel. - Cocoa: NSTabView - GTK+: ? - iOS: ?
  • TabContainer - A container view for holding an unknown number of subviews, each
    of which is of the same type - e.g., web browser tabs. - Cocoa: ? - GTK+: GtkNotebook - iOS: ?
  • NavigationContainer - A container view that holds a navigable tree of subviews;
    essentially a view that has a “back” button to return to the previous view in a heirarchy. Example of use: Top level navigation in the OS X System Preferences panel. - Cocoa: No native control - GTK+: No native control; Gtk.HeaderBar in 3.10+ - iOS: UINavigationBar + NavigationController

Dialogs and windows

GUIs aren’t all about widgets - sometimes you need to pop up a dialog to query the user.

  • Info - a modal dialog providing an “OK” option
    • Cocoa: NSAlert
    • GTK+: Gtk.MessageDialog, type Gtk.MessageType.INFO, buttons Gtk.ButtonsType.OK
    • iOS:
  • Error - a modal dialog showing an error, and a continue option.
    • Cocoa: NSAlert
    • GTK+: Gtk.MessageDialog, type Gtk.MessageType.ERROR, buttons Gtk.ButtonsType.CANCEL
    • iOS:
  • Question - a modal dialog that asks a Yes/No question
    • Cocoa: NSAlert with pre-canned buttons
    • GTK+: Gtk.MessageDialog, type Gtk.MessageType.QUESTION, buttons Gtk.ButtonsType.YES_NO
    • iOS:
  • Confirm - a modal dialog confirming “OK” or “cancel”
    • Cocoa: NSAlert with pre-canned buttons, “proceed” name
    • GTK+: Gtk.MessageDialog, type Gtk.MessageType.WARNING, buttons Gtk.ButtonsType.OK_CANCEL
    • iOS:
  • StackTrace - a modal dialog for displaying a long stack trace.
    • Cocoa: Custom NSWindow
    • GTK+: Custom Gtk.Dialog
    • iOS:
  • File Open - a mechanism for finding and specifying a file on disk.
    • Cocoa:
    • GTK+: Gtk.FileChooserDialog
    • iOS:
  • File Save - a mechanism for finding and specifying a filename to save to.
    • Cocoa:
    • GTK+:
    • iOS:


One of the aims of Toga is to provide a rich, feature-driven approach to app development. This requires the development of APIs to support rich features.

  • Long running tasks - GUI toolkits have a common pattern of needing to periodically update a GUI based on some long running background task. They usually accomplish this with some sort of timer-based API to ensure that the main event loop keeps running. Python has a “yield” keyword that can be prepurposed for this.
  • Toolbar - support for adding a toolbar to an app definition. Interpretation in mobile will be difficult; maybe some sort of top level action menu available via a slideout tray (e.g., GMail account selection tray)
  • Preferences - support for saving app preferences, and visualizing them in a platform native way.
  • Easy handling of long running tasks - possibly using generators to yield control back to the event loop.
  • Notification when updates are available
  • Easy Licening/registration of apps. Monetization is not a bad thing, and shouldn’t be mutually exclusive with open source.


Toga currently has good support for Cocoa on OS X, GTK+, and iOS. Proof-of-concept support exists for Windows Win32. Support for a more modern Windows API would be desirable.

In the mobile space, it would be great if Toga supported Android, Windows Phone, or any other phone platform.