include/wx/univ/scrthumb.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/univ/scrthumb.h
   3 // Purpose:     wxScrollThumb class
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     12.02.01
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2001 SciTech Software, Inc. (www.scitechsoft.com)
   9 // Licence:     wxWindows licence
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_UNIV_SCRTHUMB_H_
  13 #define _WX_UNIV_SCRTHUMB_H_
  14
  15 // ----------------------------------------------------------------------------
  16 // wxScrollThumb is not a control but just a class containing the common
  17 // functionality of scroll thumb such as used by scrollbars, sliders and maybe
  18 // other (user) controls
  19 //
  20 // This class is similar to wxScrollThumb.
  21 // ----------------------------------------------------------------------------
  22
  23 class WXDLLEXPORT wxControlWithThumb;
  24 class WXDLLEXPORT wxMouseEvent;
  25 class WXDLLEXPORT wxRect;
  26 class WXDLLEXPORT wxScrollTimer;
  27
  28 #include "wx/timer.h"
  29
  30 // ----------------------------------------------------------------------------
  31 // wxScrollThumb: an abstraction of scrollbar thumb
  32 // ----------------------------------------------------------------------------
  33
  34 class WXDLLEXPORT wxScrollThumb
  35 {
  36 public:
  37     enum Shaft
  38     {
  39         Shaft_None = -1,
  40         Shaft_Above,    // or to the left of the thumb
  41         Shaft_Below,    // or to the right of the thumb
  42         Shaft_Thumb,    // on the thumb
  43         Shaft_Max
  44     };
  45
  46     // ctor requires a back pointer to wxControlWithThumb
  47     wxScrollThumb(wxControlWithThumb *control);
  48
  49     // process a mouse click: will capture the mouse if the button was pressed
  50     // on either the thumb (start dragging it then) or the shaft (start
  51     // scrolling)
  52     bool HandleMouse(const wxMouseEvent& event) const;
  53
  54     // process a mouse move
  55     bool HandleMouseMove(const wxMouseEvent& event) const;
  56
  57     // dtor
  58     ~wxScrollThumb();
  59
  60 private:
  61     // do we have the mouse capture?
  62     bool HasCapture() const { return m_captureData != NULL; }
  63
  64     // get the coord of this event in the direction we're interested in (y for
  65     // vertical shaft or x for horizontal ones)
  66     wxCoord GetMouseCoord(const wxMouseEvent& event) const;
  67
  68     // get the position of the thumb corresponding to the current mouse
  69     // position (can only be called while we're dragging the thumb!)
  70     int GetThumbPos(const wxMouseEvent& event) const;
  71
  72     // the main control
  73     wxControlWithThumb *m_control;
  74
  75     // the part of it where the mouse currently is
  76     Shaft m_shaftPart;
  77
  78     // the data for the mouse capture
  79     struct WXDLLEXPORT wxScrollThumbCaptureData *m_captureData;
  80 };
  81
  82 // ----------------------------------------------------------------------------
  83 // wxControlWithThumb: interface implemented by controls using wxScrollThumb
  84 // ----------------------------------------------------------------------------
  85
  86 class WXDLLEXPORT wxControlWithThumb
  87 {
  88 public:
  89     virtual ~wxControlWithThumb() {}
  90
  91     // simple accessors
  92     // ----------------
  93
  94     // get the controls window (used for mouse capturing)
  95     virtual wxWindow *GetWindow() = 0;
  96
  97     // get the orientation of the shaft (vertical or horizontal)
  98     virtual bool IsVertical() const = 0;
  99
 100     // geometry functions
 101     // ------------------
 102
 103     // hit testing: return part of the shaft the point is in (or Shaft_None)
 104     virtual wxScrollThumb::Shaft HitTest(const wxPoint& pt) const = 0;
 105
 106     // get the current position in pixels of the thumb
 107     virtual wxCoord ThumbPosToPixel() const = 0;
 108
 109     // transform from pixel offset to the thumb logical position
 110     virtual int PixelToThumbPos(wxCoord x) const = 0;
 111
 112     // callbacks
 113     // ---------
 114
 115     // set or clear the specified flag in the arrow state: this function is
 116     // responsible for refreshing the control
 117     virtual void SetShaftPartState(wxScrollThumb::Shaft shaftPart,
 118                                    int flag,
 119                                    bool set = true) = 0;
 120
 121     // called when the user starts dragging the thumb
 122     virtual void OnThumbDragStart(int pos) = 0;
 123
 124     // called while the user drags the thumb
 125     virtual void OnThumbDrag(int pos) = 0;
 126
 127     // called when the user stops dragging the thumb
 128     virtual void OnThumbDragEnd(int pos) = 0;
 129
 130     // called before starting to call OnPageScroll() - gives the control the
 131     // possibility to remember its current state
 132     virtual void OnPageScrollStart() = 0;
 133
 134     // called while the user keeps the mouse pressed above/below the thumb,
 135     // return true to continue scrollign and false to stop it (e.g. because the
 136     // scrollbar has reached the top/bottom)
 137     virtual bool OnPageScroll(int pageInc) = 0;
 138 };
 139
 140 #endif // _WX_UNIV_SCRTHUMB_H_