GtkAccelGroup: A structure containing accelerator key data.
GtkAccelLabel: A label that can display an accelerator key next to the text.
GtkAdjustment: Represents an adjustable bounded value.
GtkAlignment: A widget that controls the alignment and size of its child.
GtkArrow: Displays an arrow pointing in one of the four cardinal directions.
GtkAspectFrame: A frame that constrains its child to a particular aspect ratio.
GtkBin: A container with just one child.
GtkBox: Base class for box containers.
GtkBoxChild: Helper class for GtkBox.
GtkButton: A container widget that emits a signal when clicked on.
GtkButtonBox: Base class for GtkHButtonBox and GtkVButtonBox.
GtkCalendar: Display a calendar and allows to select a date.
GtkCheckButton: Widget that provides a discrete check box.
GtkCheckMenuItem: Menu item with a check box.
GtkCList: A multi-columned scrolling list widget.
GtkColorSelection: Widget that allows for selection of a color.
GtkColorSelectionDialog: Standard dialog box for selecting a color.
GtkCombo: Text entry field with a dropdown list.
GtkContainer: Base class for all container widgets.
GtkCTree: Widget that displays a hierarchical tree.
GtkCurve: Widget that allows editing of a curve.
GtkData: Abstract base class for objects containing data.
GtkDialog: Widget that eases creation of popup dialogs.
GtkDrawingArea: Widget for custom user interface elements.
GtkEditable: Base class for text-editing widgets.
GtkEntry: A single line text entry field.
GtkEventBox
GtkFileSelection: Widget for selecting a file or a directory.
GtkFixed: Container that retains the sizes and positions of its children.
GtkFixedChild: Helper class for GtkFixed.
GtkFontSelection: Widget for selecting fonts.
GtkFontSelectionDialog: Standard dialog box for selecting fonts.
GtkFrame: Container with a decorative frame and an optional label.
GtkGammaCurve: A subclass of GtkCurve for editing gamma curves.
GtkHandleBox: Widget for detachable window portions.
GtkHBox: Horizontal box container.
GtkHButtonBox: Container for arranging a group of buttons horizontally.
GtkHPaned: Container with two panes arranged horizontally.
GtkHRuler: Horizontal ruler.
GtkHScale: Horizontal slider widget for selecting a value from a range.
GtkHScrollbar: Horizontall scrollbar.
GtkHSeparator: Horizontal separator.
GtkImage: Widget for displaying a graphical image.
GtkInputDialog: Standard dialog for configuring input devices.
GtkInvisible: Internally used widget which is not displayed.
GtkItem: Abstract base class for GtkMenuItem, GtkListItem, and GtkTreeItem.
GtkItemFactory
GtkLabel: Widget that displays a small amount of text.
GtkLayout
GtkList: Widget displaying a list of selectable items.
GtkListItem
GtkMenu: Popup container for menu items.
GtkMenuBar: Horizontal container for menu items.
GtkMenuItem: Widget used for item in menus.
GtkMenuShell: Abstract base class for menu objects.
GtkMisc: Base class for widgets with alignment and padding.
GtkNotebook: Widget that displays a set of pages with tabs.
GtkObject: The base class of the PHP-GTK class hierachy.
GtkOptionMenu: Widget used to choose from a list of valid choices.
GtkPacker
GtkPaned: Base class for widgets with two adjustable panes.
GtkPixmap: Widget displaying a graphical image or icon.
GtkPlug: Toplevel widget for embedding into other processes.
GtkPreview: Widget to display RGB or grayscale data.
GtkProgress: Base class for GtkProgressBar.
GtkProgressBar: Widget which indicates progress of an operation visually.
GtkRadioButton: Widget providing radio button functionality.
GtkRadioMenuItem: Widget providing radio menu item functionality.
GtkRange
GtkRuler: Base class for horizontal and vertical rulers.
GtkScale: Base class for GtkHScale and GtkVScale.
GtkScrollbar: Base class for GtkHScrollbar and GtkVScrollbar.
GtkScrolledWindow: Adds scrollbars to its child widget.
GtkSeparator: Base class for GtkHSeparator and GtkVSeparator.
GtkSocket: Container for widgets from other processes.
GtkSpinButton: Widget for setting an integer or a floating-point number.
GtkStatusbar: Widget that provides a way to report messages of minor importance.
GtkTable: Container that packs its children in regular patterns.
GtkTipsQuery: Displays help about widgets in the user interface.
GtkTearoffMenuItem: Menu item used to tear off and reattach its menu.
GtkText: Widget that allows display and manipulation of arbitrary text.
GtkToggleButton: Button widget that retains its state.
GtkToolbar: Container that creates bars of buttons and other widgets.
GtkTooltips: Adds tooltips to other widgets.
GtkTree: Widget for displaying hierarchical information.
GtkTreeItem
GtkVBox: Vertical box container.
GtkVButtonBox: Container for arranging a group of buttons vertically.
GtkViewport
GtkVPaned: Container with two panes arranged vertically.
GtkVRuler: Vertical ruler.
GtkVScale: Vertical slider widget for selecting a value from a range.
GtkVScrollbar: Vertical scrollbar.
GtkVSeparator: Vertical separator.
GtkWidget: Base class for user interface elements.
GtkWindow: Widget that provides windows for an application.
Misc Gtk Functions

II. GDK Classes