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