a GdkWindow
a state
clip rectangle, or NULL if the output should not be clipped. [allow-none]
the widget. [allow-none]
a style detail. [allow-none]
the x position to draw the expander at
the y position to draw the expander at
the style to draw the expander in; determines whether the expander is collapsed, expanded, or in an intermediate state.
Draws an expander as used in GtkTreeView. x and y specify the center the expander. The size of the expander is determined by the "expander-size" style property of widget. (If widget is not specified or doesn't have an "expander-size" property, an unspecified default size will be used, since the caller doesn't have sufficient information to position the expander, this is likely not useful.) The expander is expander_size pixels tall in the collapsed position and expander_size pixels wide in the expanded position.