ControlContext :: line - Get currently selected line
The function returns the line for the currently selected list item in a tree. When no line is selected in the control, no list item will be attached to the line and the the list item identifier for the line returned is 0, i.e. the line is invalid (Line::isValid()).
Return value: Constant line ( odabagui::Line & )
The line passed may have any state, i.e. it night be attached to a list item or not. The line might even be empty.