Set the image of button to the given widget. The image will be displayed if the label text is NULL or if "always-show-image" is TRUE. You don't have to call gtk_widget_show() on image yourself. Since 2.6
a widget to set as the image for the button
See Implementation
Set the image of button to the given widget. The image will be displayed if the label text is NULL or if "always-show-image" is TRUE. You don't have to call gtk_widget_show() on image yourself. Since 2.6