src/common/helpbase.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        helpbase.cpp
   3 // Purpose:     Help system base classes
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart and Markus Holzem
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifdef __GNUG__
  13 #pragma implementation "helpbase.h"
  14 #endif
  15
  16 // For compilers that support precompilation, includes "wx.h".
  17 #include "wx/wxprec.h"
  18
  19 #ifdef __BORLANDC__
  20 #pragma hdrstop
  21 #endif
  22
  23 #ifndef WX_PRECOMP
  24 #include "wx/defs.h"
  25 #endif
  26
  27 #include "wx/helpbase.h"
  28 #include "wx/app.h"
  29
  30 #if wxUSE_HELP
  31
  32 IMPLEMENT_CLASS(wxHelpControllerBase, wxObject)
  33
  34 /*
  35  * Invokes context-sensitive help
  36  */
  37
  38 // This class exists in order to eat events until the left mouse
  39 // button is pressed
  40 class wxContextHelpEvtHandler: public wxEvtHandler
  41 {
  42 public:
  43     wxContextHelpEvtHandler(wxContextHelp* contextHelp)
  44     {
  45         m_contextHelp = contextHelp;
  46     }
  47
  48     virtual bool ProcessEvent(wxEvent& event);
  49
  50 //// Data
  51     wxContextHelp* m_contextHelp;
  52 };
  53
  54 IMPLEMENT_DYNAMIC_CLASS(wxContextHelp, wxObject)
  55
  56 wxContextHelp::wxContextHelp(wxWindow* win, bool beginHelp)
  57 {
  58     m_inHelp = FALSE;
  59
  60     if (beginHelp)
  61         BeginContextHelp(win);
  62 }
  63
  64 wxContextHelp::~wxContextHelp()
  65 {
  66     if (m_inHelp)
  67         EndContextHelp();
  68 }
  69
  70 // Begin 'context help mode'
  71 bool wxContextHelp::BeginContextHelp(wxWindow* win)
  72 {
  73     if (!win)
  74         win = wxTheApp->GetTopWindow();
  75     if (!win)
  76         return FALSE;
  77
  78     wxCursor cursor(wxCURSOR_QUESTION_ARROW);
  79     wxCursor oldCursor = win->GetCursor();
  80     win->SetCursor(cursor);
  81     wxSetCursor(cursor);
  82
  83     win->PushEventHandler(new wxContextHelpEvtHandler(this));
  84
  85     win->CaptureMouse();
  86
  87     EventLoop();
  88
  89     win->ReleaseMouse();
  90
  91     win->PopEventHandler(TRUE);
  92
  93     win->SetCursor(oldCursor);
  94
  95     if (m_status)
  96     {
  97         wxPoint pt;
  98         wxWindow* winAtPtr = wxFindWindowAtPointer(pt);
  99         if (winAtPtr)
 100             DispatchEvent(winAtPtr, pt);
 101     }
 102
 103     return TRUE;
 104 }
 105
 106 bool wxContextHelp::EndContextHelp()
 107 {
 108     m_inHelp = FALSE;
 109
 110     return TRUE;
 111 }
 112
 113 bool wxContextHelp::EventLoop()
 114 {
 115     m_inHelp = TRUE;
 116     while ( m_inHelp )
 117     {
 118         if (wxTheApp->Pending())
 119         {
 120             wxTheApp->Dispatch();
 121         }
 122         else
 123         {
 124             wxTheApp->ProcessIdle();
 125         }
 126     }
 127     return TRUE;
 128 }
 129
 130 bool wxContextHelpEvtHandler::ProcessEvent(wxEvent& event)
 131 {
 132     switch (event.GetEventType())
 133     {
 134         case wxEVT_LEFT_DOWN:
 135         {
 136             wxMouseEvent& mouseEvent = (wxMouseEvent&) event;
 137             m_contextHelp->SetStatus(TRUE);
 138             m_contextHelp->EndContextHelp();
 139             return TRUE;
 140             break;
 141         }
 142         case wxEVT_CHAR:
 143         case wxEVT_KEY_DOWN:
 144         case wxEVT_ACTIVATE:
 145         case wxEVT_MOUSE_CAPTURE_CHANGED:
 146         {
 147             m_contextHelp->SetStatus(FALSE);
 148             m_contextHelp->EndContextHelp();
 149             return TRUE;
 150             break;
 151         }
 152         case wxEVT_PAINT:
 153         case wxEVT_ERASE_BACKGROUND:
 154         {
 155             event.Skip();
 156             return FALSE;
 157             break;
 158         }
 159     }
 160
 161     return TRUE;
 162 }
 163
 164 // Dispatch the help event to the relevant window
 165 bool wxContextHelp::DispatchEvent(wxWindow* win, const wxPoint& pt)
 166 {
 167     wxWindow* subjectOfHelp = win;
 168     bool eventProcessed = FALSE;
 169     while (subjectOfHelp && !eventProcessed)
 170     {
 171         wxHelpEvent helpEvent(wxEVT_HELP, subjectOfHelp->GetId(), pt) ;
 172         helpEvent.SetEventObject(this);
 173         eventProcessed = win->GetEventHandler()->ProcessEvent(helpEvent);
 174
 175         // Go up the window hierarchy until the event is handled (or not).
 176         // I.e. keep submitting ancestor windows until one is recognised
 177         // by the app code that processes the ids and displays help.
 178         subjectOfHelp = subjectOfHelp->GetParent();
 179     }
 180     return eventProcessed;
 181 }
 182
 183 #endif // wxUSE_HELP