Qwt User's Guide  6.1.3
QwtPickerDragLineMachine Class Reference

A state machine for line selections. More...

#include <qwt_picker_machine.h>

Inheritance diagram for QwtPickerDragLineMachine:

Public Member Functions

 QwtPickerDragLineMachine ()
virtual QList< Commandtransition (const QwtEventPattern &, const QEvent *)
- Public Member Functions inherited from QwtPickerMachine
 QwtPickerMachine (SelectionType)
virtual ~QwtPickerMachine ()
void reset ()
 Set the current state to 0.
int state () const
 Return the current state.
void setState (int)
 Change the current state.
SelectionType selectionType () const
 Return the selection type.

Additional Inherited Members

- Public Types inherited from QwtPickerMachine
enum  SelectionType { NoSelection = -1, PointSelection, RectSelection, PolygonSelection }
enum  Command {
  Begin, Append, Move, Remove,
 Commands - the output of a state machine.

Detailed Description

A state machine for line selections.

Pressing QwtEventPattern::MouseSelect1 selects the first point, releasing it the second point. Pressing QwtEventPattern::KeySelect1 also selects the first point, a second press selects the second point and terminates the selection.

A common use case of QwtPickerDragLineMachine are pickers for distance measurements.

See also
QwtEventPattern::MousePatternCode, QwtEventPattern::KeyPatternCode