src/TortoiseIDiff/NiceTrackbar.cpp

   1 // TortoiseIDiff - an image diff viewer in TortoiseSVN
   2
   3 // Copyright (C) 2006-2008, 2011 - TortoiseSVN
   4
   5 // This program is free software; you can redistribute it and/or
   6 // modify it under the terms of the GNU General Public License
   7 // as published by the Free Software Foundation; either version 2
   8 // of the License, or (at your option) any later version.
   9
  10 // This program is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14
  15 // You should have received a copy of the GNU General Public License
  16 // along with this program; if not, write to the Free Software Foundation,
  17 // 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 //
  19 #include "stdafx.h"
  20 #include "NiceTrackbar.h"
  21 #include <CommCtrl.h>
  22 #include <WindowsX.h>
  23
  24
  25 LRESULT CALLBACK CNiceTrackbar::NiceTrackbarProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
  26 {
  27     auto self = reinterpret_cast<CNiceTrackbar*>(GetWindowLongPtr(hwnd, GWLP_USERDATA));
  28
  29     switch (message) {
  30     case WM_LBUTTONDOWN:
  31         self->m_Dragging = true;
  32         self->m_DragChanged = false;
  33         SetCapture(hwnd);
  34         //SetFocus(hwnd);
  35         if (self->SetThumb(lParam)) {
  36             self->m_DragChanged = true;
  37             self->PostMessageToParent(TB_THUMBTRACK);
  38         }
  39         return 0;
  40     case WM_MOUSEMOVE:
  41         if (self->m_Dragging)
  42         {
  43             if (self->SetThumb(lParam))
  44             {
  45                 self->m_DragChanged = true;
  46                 self->PostMessageToParent(TB_THUMBTRACK);
  47             }
  48             return 0;
  49         }
  50         break;
  51     case WM_LBUTTONUP:
  52         if (self->m_Dragging)
  53         {
  54             self->m_Dragging = false;
  55             ReleaseCapture();
  56             if (self->SetThumb(lParam))
  57             {
  58                 self->PostMessageToParent(TB_ENDTRACK);
  59                 self->m_DragChanged = true;
  60             }
  61             if (self->m_DragChanged)
  62             {
  63                 self->PostMessageToParent(TB_THUMBPOSITION);
  64                 self->m_DragChanged = false;
  65             }
  66             return 0;
  67         }
  68         break;
  69     case WM_CAPTURECHANGED:
  70         if (self->m_Dragging)
  71         {
  72             self->m_Dragging = false;
  73             return 0;
  74         }
  75         break;
  76     case WM_DESTROY:
  77         SetWindowLongPtr(hwnd, GWLP_WNDPROC, reinterpret_cast<LONG_PTR>(self->m_OrigProc));
  78         break;
  79     }
  80     return CallWindowProc (self->m_OrigProc, hwnd, message, wParam, lParam);
  81 }
  82
  83
  84 void CNiceTrackbar::ConvertTrackbarToNice( HWND window )
  85 {
  86     m_Window = window;
  87
  88     // setup this pointer
  89     SetWindowLongPtr(window, GWLP_USERDATA, reinterpret_cast<LONG_PTR>(this));
  90
  91     // subclass it
  92     m_OrigProc = reinterpret_cast<WNDPROC>(SetWindowLongPtr(window, GWLP_WNDPROC, reinterpret_cast<LONG_PTR>(NiceTrackbarProc)));
  93 }
  94
  95
  96 bool CNiceTrackbar::SetThumb (LPARAM lparamPoint)
  97 {
  98     POINT point = { GET_X_LPARAM(lparamPoint), GET_Y_LPARAM(lparamPoint) };
  99     const int nMin = static_cast<int>(SendMessage(m_Window, TBM_GETRANGEMIN, 0, 0l));
 100     const int nMax = static_cast<int>(SendMessage(m_Window, TBM_GETRANGEMAX, 0, 0l));
 101     RECT rc;
 102     SendMessage(m_Window, TBM_GETCHANNELRECT, 0, reinterpret_cast<LPARAM>(&rc));
 103     double ratio;
 104     if (GetWindowLong(m_Window, GWL_STYLE) & TBS_VERT)
 105     {
 106         // note: for vertical trackbar, it still returns the rectangle as if it was horizontal
 107         ratio = static_cast<double>(point.y - rc.left)/(rc.right - rc.left);
 108     }
 109     else
 110     {
 111         ratio = static_cast<double>(point.x - rc.left)/(rc.right - rc.left);
 112     }
 113
 114     int nNewPos = static_cast<int>(nMin + (nMax-nMin) * ratio + 0.5); // round the result to go to the nearest tick mark
 115
 116     const bool changed = (nNewPos != static_cast<int>(SendMessage(m_Window, TBM_GETPOS, 0, 0)));
 117     if (changed)
 118     {
 119         SendMessage(m_Window, TBM_SETPOS, TRUE, nNewPos);
 120     }
 121     return changed;
 122 }
 123
 124
 125 void CNiceTrackbar::PostMessageToParent (int tbCode) const
 126 {
 127     HWND parent = GetParent(m_Window);
 128     if (parent)
 129     {
 130         int pos = static_cast<int>(SendMessage(m_Window, TBM_GETPOS, 0, 0));
 131         bool vert = (GetWindowLong(m_Window, GWL_STYLE) & TBS_VERT) != 0;
 132         PostMessage( parent, vert ? WM_VSCROLL : WM_HSCROLL, ((pos << 16) | tbCode), reinterpret_cast<LPARAM>(m_Window) );
 133     }
 134 }