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 #ifdef __GNUG__
  16     #pragma interface "scrthumb.h"
  17 #endif
  18
  19 // ----------------------------------------------------------------------------
  20 // wxScrollThumb is not a control but just a class containing the common
  21 // functionality of scroll thumb such as used by scrollbars, sliders and maybe
  22 // other (user) controls
  23 //
  24 // This class is similar to wxScrollThumb.
  25 // ----------------------------------------------------------------------------
  26
  27 class WXDLLEXPORT wxControlWithThumb;
  28 class WXDLLEXPORT wxMouseEvent;
  29 class WXDLLEXPORT wxRect;
  30 class WXDLLEXPORT wxScrollTimer;
  31
  32 #include "wx/timer.h"
  33
  34 // ----------------------------------------------------------------------------
  35 // wxScrollThumb: an abstraction of scrollbar thumb
  36 // ----------------------------------------------------------------------------
  37
  38 class WXDLLEXPORT wxScrollThumb
  39 {
  40 public:
  41     enum Shaft
  42     {
  43         Shaft_None = -1,
  44         Shaft_Above,    // or to the left of the thumb
  45         Shaft_Below,    // or to the right of the thumb
  46         Shaft_Thumb,    // on the thumb
  47         Shaft_Max
  48     };
  49
  50     // ctor requires a back pointer to wxControlWithThumb
  51     wxScrollThumb(wxControlWithThumb *control);
  52
  53     // process a mouse click: will capture the mouse if the button was pressed
  54     // on either the thumb (start dragging it then) or the shaft (start
  55     // scrolling)
  56     bool HandleMouse(const wxMouseEvent& event) const;
  57
  58     // process a mouse move
  59     bool HandleMouseMove(const wxMouseEvent& event) const;
  60
  61     // dtor
  62     ~wxScrollThumb();
  63
  64 private:
  65     // do we have the mouse capture?
  66     bool HasCapture() const { return m_captureData != NULL; }
  67
  68     // get the coord of this event in the direction we're interested in (y for
  69     // vertical shaft or x for horizontal ones)
  70     wxCoord GetMouseCoord(const wxMouseEvent& event) const;
  71
  72     // get the position of the thumb corresponding to the current mouse
  73     // position (can only be called while we're dragging the thumb!)
  74     int GetThumbPos(const wxMouseEvent& event) const;
  75
  76     // the main control
  77     wxControlWithThumb *m_control;
  78
  79     // the part of it where the mouse currently is
  80     Shaft m_shaftPart;
  81
  82     // the data for the mouse capture
  83     struct WXDLLEXPORT wxScrollThumbCaptureData *m_captureData;
  84 };
  85
  86 // ----------------------------------------------------------------------------
  87 // wxControlWithThumb: interface implemented by controls using wxScrollThumb
  88 // ----------------------------------------------------------------------------
  89
  90 class WXDLLEXPORT wxControlWithThumb
  91 {
  92 public:
  93     // simple accessors
  94     // ----------------
  95
  96     // get the controls window (used for mouse capturing)
  97     virtual wxWindow *GetWindow() = 0;
  98
  99     // get the orientation of the shaft (vertical or horizontal)
 100     virtual bool IsVertical() const = 0;
 101
 102     // geometry functions
 103     // ------------------
 104
 105     // hit testing: return part of the shaft the point is in (or Shaft_None)
 106     virtual wxScrollThumb::Shaft HitTest(const wxPoint& pt) const = 0;
 107
 108     // get the current position in pixels of the thumb
 109     virtual wxCoord ThumbPosToPixel() const = 0;
 110
 111     // transform from pixel offset to the thumb logical position
 112     virtual int PixelToThumbPos(wxCoord x) const = 0;
 113
 114     // callbacks
 115     // ---------
 116
 117     // set or clear the specified flag in the arrow state: this function is
 118     // responsible for refreshing the control
 119     virtual void SetShaftPartState(wxScrollThumb::Shaft shaftPart,
 120                                    int flag,
 121                                    bool set = TRUE) = 0;
 122
 123     // called when the user starts dragging the thumb
 124     virtual void OnThumbDragStart(int pos) = 0;
 125
 126     // called while the user drags the thumb
 127     virtual void OnThumbDrag(int pos) = 0;
 128
 129     // called when the user stops dragging the thumb
 130     virtual void OnThumbDragEnd(int pos) = 0;
 131
 132     // called before starting to call OnPageScroll() - gives the control the
 133     // possibility to remember its current state
 134     virtual void OnPageScrollStart() = 0;
 135
 136     // called while the user keeps the mouse pressed above/below the thumb,
 137     // return TRUE to continue scrollign and FALSE to stop it (e.g. because the
 138     // scrollbar has reached the top/bottom)
 139     virtual bool OnPageScroll(int pageInc) = 0;
 140 };
 141
 142 #endif // _WX_UNIV_SCRTHUMB_H_