gboolean shumate_marker_layer_select_marker ( ShumateMarkerLayer* self, ShumateMarker* marker )
Selects a marker in this layer.
GTK_SELECTION_BROWSE, all other markers will be unselected. If the mode is
marker is not selectable, nothing will happen.
ShumateMarkerthat is a child of
The data is owned by the caller of the method.