Windows

    GtkDialog — Create popup windows
    GtkInvisible — A widget which is not displayed
    GtkMessageDialog — A convenient message window
    GtkWindow — Toplevel which can contain other widgets
    GtkWindowGroup — Limit the effect of grabs
    GtkAboutDialog — Display information about an application
    GtkAssistant — A widget used to guide users through multi-step operations

Display Widgets

    GtkAccelLabel — A label which displays an accelerator key on the right of the text
    GtkImage — A widget displaying an image
    GtkLabel — A widget that displays a small to medium amount of text
    GtkProgressBar — A widget which indicates progress visually
    GtkStatusbar — Report messages of minor importance to the user
    GtkStatusIcon — Display an icon in the system tray

Buttons and Toggles

    GtkButton — A widget that creates a signal when clicked on
    GtkCheckButton — Create widgets with a discrete toggle button
    GtkRadioButton — A choice from multiple check buttons
    GtkToggleButton — Create buttons which retain their state
    GtkLinkButton — Create buttons bound to a URL
    GtkScaleButton — A button which pops up a scale
    GtkVolumeButton — A button which pops up a volume control

Numeric/Text Data Entry

    GtkEntry — A single line text entry field
    GtkEntryCompletion — Completion functionality for GtkEntry
    GtkHScale — A horizontal slider widget for selecting a value from a range
    GtkVScale — A vertical slider widget for selecting a value from a range
    GtkSpinButton — Retrieve an integer or floating-point number from the user
    GtkEditable — Interface for text-editing widgets

Multiline Text Editor

    Text Widget Overview — Overview of GtkTextBuffer, GtkTextView, and friends
    GtkTextIter — Text buffer iterator
    GtkTextMark — A position in the buffer preserved across buffer modifications
    GtkTextBuffer — Stores attributed text for display in a GtkTextView
    GtkTextTag — A tag that can be applied to text in a GtkTextBuffer
    GtkTextTagTable — Collection of tags that can be used together
    GtkTextView — Widget that displays a GtkTextBuffer

Tree, List and Icon Grid Widgets

    Tree and List Widget Overview — Overview of GtkTreeModel, GtkTreeView, and friends
    GtkTreeModel — The tree interface used by GtkTreeView
    GtkTreeSelection — The selection object for GtkTreeView
    GtkTreeViewColumn — A visible column in a GtkTreeView widget
    GtkTreeView — A widget for displaying both trees and lists
    GtkTreeView drag-and-drop — Interfaces for drag-and-drop support in GtkTreeView
    GtkCellView — A widget displaying a single row of a GtkTreeModel
    GtkIconView — A widget which displays a list of icons in a grid
    GtkTreeSortable — The interface for sortable models used by GtkTreeView
    GtkTreeModelSort — A GtkTreeModel which makes an underlying tree model sortable
    GtkTreeModelFilter — A GtkTreeModel which hides parts of an underlying tree model
    GtkCellLayout — An interface for packing cells
    GtkCellRenderer — An object for rendering a single cell on a GdkDrawable
    GtkCellEditable — Interface for widgets which can are used for editing cells
    GtkCellRendererAccel — Renders a keyboard accelerator in a cell
    GtkCellRendererCombo — Renders a combobox in a cell
    GtkCellRendererPixbuf — Renders a pixbuf in a cell
    GtkCellRendererProgress — Renders numbers as progress bars
    GtkCellRendererSpin — Renders a spin button in a cell
    GtkCellRendererText — Renders text in a cell
    GtkCellRendererToggle — Renders a toggle button in a cell
    GtkListStore — A list-like data structure that can be used with the GtkTreeView
    GtkTreeStore — A tree-like data structure that can be used with the GtkTreeView

Menus, Combo Box, Toolbar

    GtkComboBox — A widget used to choose from a list of items
    GtkComboBoxEntry — A text entry field with a dropdown list
    GtkMenu — A menu widget
    GtkMenuBar — A subclass widget for GtkMenuShell which holds GtkMenuItem widgets
    GtkMenuItem — The widget used for item in menus
    GtkImageMenuItem — A menu item with an icon
    GtkRadioMenuItem — A choice from multiple check menu items
    GtkCheckMenuItem — A menu item with a check box
    GtkSeparatorMenuItem — A separator used in menus
    GtkTearoffMenuItem — A menu item used to tear off and reattach its menu
    GtkToolbar — Create bars of buttons and other widgets
    GtkToolItem — The base class of widgets that can be added to GtkToolbar
    GtkSeparatorToolItem — A toolbar item that separates groups of other toolbar items
    GtkToolButton — A GtkToolItem subclass that displays buttons
    GtkMenuToolButton — A GtkToolItem containing a button with an additional dropdown menu
    GtkToggleToolButton — A GtkToolItem containing a toggle button
    GtkRadioToolButton — A toolbar item that contains a radio button

Action-based menus and toolbars

    GtkUIManager — Constructing menus and toolbars from an XML description
    GtkActionGroup — A group of actions
    GtkAction — An action which can be triggered by a menu or toolbar item
    GtkToggleAction — An action which can be toggled between two states
    GtkRadioAction — An action of which only one in a group can be active
    GtkRecentAction — An action of which represents a list of recently used files

Selectors (File/Font/Color/Input Devices)

    GtkColorButton — A button to launch a color selection dialog
    GtkColorSelection — A widget used to select a color
    GtkColorSelectionDialog — A standard dialog box for selecting a color
    GtkFileSelection — Prompt the user for a file or directory name
    GtkFileChooser — File chooser interface used by GtkFileChooserWidget and GtkFileChooserDialog
    GtkFileChooserButton — A button to launch a file selection dialog
    GtkFileChooserDialog — A file chooser dialog, suitable for "File/Open" or "File/Save" commands
    GtkFileChooserWidget — File chooser widget that can be embedded in other widgets
    GtkFileFilter — A filter for selecting a file subset
    GtkFontButton — A button to launch a font selection dialog
    GtkFontSelection — A widget for selecting fonts
    GtkFontSelectionDialog — A dialog box for selecting fonts
    GtkInputDialog — Configure devices for the XInput extension

Layout Containers

    GtkAlignment — A widget which controls the alignment and size of its child
    GtkAspectFrame — A frame that constrains its child to a particular aspect ratio
    GtkHBox — A horizontal container box
    GtkVBox — A vertical container box
    GtkHButtonBox — A container for arranging buttons horizontally
    GtkVButtonBox — A container for arranging buttons vertically
    GtkFixed — A container which allows you to position widgets at fixed coordinates
    GtkHPaned — A container with two panes arranged horizontally
    GtkVPaned — A container with two panes arranged vertically
    GtkLayout — Infinite scrollable area containing child widgets and/or custom drawing
    GtkNotebook — A tabbed notebook container
    GtkTable — Pack widgets in regular patterns
    GtkExpander — A container which can hide its child

Ornaments

    GtkFrame — A bin with a decorative frame and optional label
    GtkHSeparator — A horizontal separator
    GtkVSeparator — A vertical separator

Scrolling

    GtkHScrollbar — A horizontal scrollbar
    GtkVScrollbar
    GtkScrolledWindow — Adds scrollbars to its child widget

Printing

    GtkPrintOperation — High-level Printing API
    GtkPrintContext — Encapsulates context for drawing pages
    GtkPrintSettings — Stores print settings
    GtkPageSetup — Stores page setup information
    GtkPaperSize — Support for named paper sizes
    GtkPrinter — Represents a printer
    GtkPrintJob — Represents a print job
    GtkPrintUnixDialog — A print dialog
    GtkPageSetupUnixDialog — A page setup dialog

Miscellaneous

    GtkAdjustment — A GtkObject representing an adjustable bounded value
    GtkArrow — Displays an arrow
    GtkCalendar — Displays a calendar and allows the user to select a date
    GtkDrawingArea — A widget for custom user interface elements
    GtkEventBox — A widget used to catch events for widgets which do not have their own window
    GtkHandleBox — a widget for detachable window portions
    GtkIMContextSimple — An input method context supporting table-based input methods
    GtkIMMulticontext — An input method context supporting multiple, loadable input methods
    GtkSizeGroup — Grouping widgets so they request the same size
    GtkTooltip — Add tips to your widgets
    GtkTooltips — Add tips to your widgets
    GtkViewport — An adapter which makes widgets scrollable
    GtkAccessible — Accessibility support for widgets

Abstract Base Classes

    GtkBin — A container with just one child
    GtkBox — Base class for box containers
    GtkButtonBox — Base class for GtkHButtonBox and GtkVButtonBox
    GtkContainer — Base class for widgets which contain other widgets
    GtkItem — Abstract base class for GtkMenuItem, GtkListItem and GtkTreeItem
    GtkMenuShell — A base class for menu objects
    GtkMisc — Base class for widgets with alignments and padding
    GtkObject — The base class of the GTK+ type hierarchy
    GtkPaned — Base class for widgets with two adjustable panes
    GtkRange — Base class for widgets which visualize an adjustment
    GtkScale — Base class for GtkHScale and GtkVScale
    GtkScrollbar — Base class for GtkHScrollbar and GtkVScrollbar
    GtkSeparator — Base class for GtkHSeparator and GtkVSeparator
    GtkWidget — Base class for all widgets
    GtkIMContext — Base class for input method contexts

Cross-process Embedding

    GtkPlug — Toplevel for embedding into other processes
    GtkSocket — Container for widgets from other processes

Special-purpose features

    GtkCurve — Allows direct editing of a curve
    GtkGammaCurve — A subclass of GtkCurve for editing gamma curves
    GtkRuler — Base class for horizontal or vertical rulers
    GtkHRuler — A horizontal ruler
    GtkVRuler — A vertical ruler

Recently Used Documents

    GtkRecentManager — Managing Recently Used Files
    GtkRecentChooser — Interface implemented by widgets displaying recently used files
    GtkRecentChooserDialog — Displays recently used files in a dialog
    GtkRecentChooserMenu — Displays recently used files in a menu
    GtkRecentChooserWidget — Displays recently used files
    GtkRecentFilter — A filter for selecting a subset of recently used files

Interface builder

    GtkBuildable — Interface for objects that can be built by GtkBuilder
    GtkBuilder — Build an interface from an XML UI definition

Deprecated

    GtkCList — A multi-columned scrolling list widget
    GtkCTree — A widget displaying a hierarchical tree
    GtkCombo — A text entry field with a dropdown list
    GtkItemFactory — A factory for menus
    GtkList — Widget for packing a list of selectable items
    GtkListItem — An item in a GtkList
    GtkOldEditable — Base class for text-editing widgets
    GtkOptionMenu — A widget used to choose from a list of valid choices
    GtkPixmap — A widget displaying a graphical image or icon
    GtkPreview — A widget to display RGB or grayscale data
    GtkProgress — Base class for GtkProgressBar
    GtkText — A text widget
    GtkTipsQuery — Displays help about widgets in the user interface
    GtkTree — A tree widget
    GtkTreeItem — The widget used for items in a GtkTree

