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