src/common/cmdproc.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/cmdproc.cpp
   3 // Purpose:     wxCommand and wxCommandProcessor classes
   4 // Author:      Julian Smart (extracted from docview.h by VZ)
   5 // Modified by:
   6 // Created:     05.11.00
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) wxWidgets team
   9 // Licence:     wxWindows licence
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  21     #pragma implementation "cmdproc.h"
  22 #endif
  23
  24 // For compilers that support precompilation, includes "wx.h".
  25 #include "wx/wxprec.h"
  26
  27 #ifdef __BORLANDC__
  28     #pragma hdrstop
  29 #endif
  30
  31 #ifndef WX_PRECOMP
  32     #include "wx/intl.h"
  33     #include "wx/string.h"
  34     #include "wx/menu.h"
  35 #endif //WX_PRECOMP
  36
  37 #include "wx/cmdproc.h"
  38
  39 // ============================================================================
  40 // implementation
  41 // ============================================================================
  42
  43 IMPLEMENT_CLASS(wxCommand, wxObject)
  44 IMPLEMENT_DYNAMIC_CLASS(wxCommandProcessor, wxObject)
  45
  46 // ----------------------------------------------------------------------------
  47 // wxCommand
  48 // ----------------------------------------------------------------------------
  49
  50 wxCommand::wxCommand(bool canUndoIt, const wxString& name)
  51 {
  52     m_canUndo = canUndoIt;
  53     m_commandName = name;
  54 }
  55
  56 // ----------------------------------------------------------------------------
  57 // Command processor
  58 // ----------------------------------------------------------------------------
  59
  60 wxCommandProcessor::wxCommandProcessor(int maxCommands)
  61 {
  62     m_maxNoCommands = maxCommands;
  63 #if wxUSE_MENUS
  64     m_commandEditMenu = (wxMenu *) NULL;
  65 #endif // wxUSE_MENUS
  66     m_undoAccelerator = wxT("\tCtrl+Z");
  67     m_redoAccelerator = wxT("\tCtrl+Y");
  68
  69     m_lastSavedCommand =
  70     m_currentCommand = wxList::compatibility_iterator();
  71 }
  72
  73 wxCommandProcessor::~wxCommandProcessor()
  74 {
  75     ClearCommands();
  76 }
  77
  78 bool wxCommandProcessor::DoCommand(wxCommand& cmd)
  79 {
  80     return cmd.Do();
  81 }
  82
  83 bool wxCommandProcessor::UndoCommand(wxCommand& cmd)
  84 {
  85     return cmd.Undo();
  86 }
  87
  88 // Pass a command to the processor. The processor calls Do();
  89 // if successful, is appended to the command history unless
  90 // storeIt is false.
  91 bool wxCommandProcessor::Submit(wxCommand *command, bool storeIt)
  92 {
  93     wxCHECK_MSG( command, false, _T("no command in wxCommandProcessor::Submit") );
  94
  95     if ( !DoCommand(*command) )
  96     {
  97         // the user code expects the command to be deleted anyhow
  98         delete command;
  99
 100         return false;
 101     }
 102
 103     if ( storeIt )
 104         Store(command);
 105     else
 106         delete command;
 107
 108     return true;
 109 }
 110
 111 void wxCommandProcessor::Store(wxCommand *command)
 112 {
 113     wxCHECK_RET( command, _T("no command in wxCommandProcessor::Store") );
 114
 115     if ( (int)m_commands.GetCount() == m_maxNoCommands )
 116     {
 117         wxList::compatibility_iterator firstNode = m_commands.GetFirst();
 118         wxCommand *firstCommand = (wxCommand *)firstNode->GetData();
 119         delete firstCommand;
 120         m_commands.Erase(firstNode);
 121
 122         // Make sure m_lastSavedCommand won't point to freed memory
 123         if ( m_lastSavedCommand == firstNode )
 124             m_lastSavedCommand = wxList::compatibility_iterator();
 125     }
 126
 127     // Correct a bug: we must chop off the current 'branch'
 128     // so that we're at the end of the command list.
 129     if (!m_currentCommand)
 130         ClearCommands();
 131     else
 132     {
 133         wxList::compatibility_iterator node = m_currentCommand->GetNext();
 134         while (node)
 135         {
 136             wxList::compatibility_iterator next = node->GetNext();
 137             delete (wxCommand *)node->GetData();
 138             m_commands.Erase(node);
 139
 140             // Make sure m_lastSavedCommand won't point to freed memory
 141             if ( m_lastSavedCommand == node )
 142                 m_lastSavedCommand = wxList::compatibility_iterator();
 143
 144             node = next;
 145         }
 146     }
 147
 148     m_commands.Append(command);
 149     m_currentCommand = m_commands.GetLast();
 150     SetMenuStrings();
 151 }
 152
 153 bool wxCommandProcessor::Undo()
 154 {
 155     wxCommand *command = GetCurrentCommand();
 156     if ( command && command->CanUndo() )
 157     {
 158         if ( UndoCommand(*command) )
 159         {
 160             m_currentCommand = m_currentCommand->GetPrevious();
 161             SetMenuStrings();
 162             return true;
 163         }
 164     }
 165
 166     return false;
 167 }
 168
 169 bool wxCommandProcessor::Redo()
 170 {
 171     wxCommand *redoCommand = (wxCommand *) NULL;
 172     wxList::compatibility_iterator redoNode
 173 #if !wxUSE_STL
 174         = NULL          // just to avoid warnings
 175 #endif // !wxUSE_STL
 176         ;
 177
 178     if ( m_currentCommand )
 179     {
 180         // is there anything to redo?
 181         if ( m_currentCommand->GetNext() )
 182         {
 183             redoCommand = (wxCommand *)m_currentCommand->GetNext()->GetData();
 184             redoNode = m_currentCommand->GetNext();
 185         }
 186     }
 187     else // no current command, redo the first one
 188     {
 189         if (m_commands.GetCount() > 0)
 190         {
 191             redoCommand = (wxCommand *)m_commands.GetFirst()->GetData();
 192             redoNode = m_commands.GetFirst();
 193         }
 194     }
 195
 196     if (redoCommand)
 197     {
 198         bool success = DoCommand(*redoCommand);
 199         if (success)
 200         {
 201             m_currentCommand = redoNode;
 202             SetMenuStrings();
 203             return true;
 204         }
 205     }
 206     return false;
 207 }
 208
 209 bool wxCommandProcessor::CanUndo() const
 210 {
 211     wxCommand *command = GetCurrentCommand();
 212
 213     return command && command->CanUndo();
 214 }
 215
 216 bool wxCommandProcessor::CanRedo() const
 217 {
 218     if (m_currentCommand && !m_currentCommand->GetNext())
 219         return false;
 220
 221     if (m_currentCommand && m_currentCommand->GetNext())
 222         return true;
 223
 224     if (!m_currentCommand && (m_commands.GetCount() > 0))
 225         return true;
 226
 227     return false;
 228 }
 229
 230 void wxCommandProcessor::Initialize()
 231 {
 232     m_currentCommand = m_commands.GetLast();
 233     SetMenuStrings();
 234 }
 235
 236 void wxCommandProcessor::SetMenuStrings()
 237 {
 238 #if wxUSE_MENUS
 239     if (m_commandEditMenu)
 240     {
 241         wxString undoLabel = GetUndoMenuLabel();
 242         wxString redoLabel = GetRedoMenuLabel();
 243
 244         m_commandEditMenu->SetLabel(wxID_UNDO, undoLabel);
 245         m_commandEditMenu->Enable(wxID_UNDO, CanUndo());
 246
 247         m_commandEditMenu->SetLabel(wxID_REDO, redoLabel);
 248         m_commandEditMenu->Enable(wxID_REDO, CanRedo());
 249     }
 250 #endif // wxUSE_MENUS
 251 }
 252
 253 // Gets the current Undo menu label.
 254 wxString wxCommandProcessor::GetUndoMenuLabel() const
 255 {
 256     wxString buf;
 257     if (m_currentCommand)
 258     {
 259         wxCommand *command = (wxCommand *)m_currentCommand->GetData();
 260         wxString commandName(command->GetName());
 261         if (commandName.empty()) commandName = _("Unnamed command");
 262         bool canUndo = command->CanUndo();
 263         if (canUndo)
 264             buf = wxString(_("&Undo ")) + commandName + m_undoAccelerator;
 265         else
 266             buf = wxString(_("Can't &Undo ")) + commandName + m_undoAccelerator;
 267     }
 268     else
 269     {
 270         buf = _("&Undo") + m_undoAccelerator;
 271     }
 272
 273     return buf;
 274 }
 275
 276 // Gets the current Undo menu label.
 277 wxString wxCommandProcessor::GetRedoMenuLabel() const
 278 {
 279     wxString buf;
 280     if (m_currentCommand)
 281     {
 282         // We can redo, if we're not at the end of the history.
 283         if (m_currentCommand->GetNext())
 284         {
 285             wxCommand *redoCommand = (wxCommand *)m_currentCommand->GetNext()->GetData();
 286             wxString redoCommandName(redoCommand->GetName());
 287             if (redoCommandName.empty()) redoCommandName = _("Unnamed command");
 288             buf = wxString(_("&Redo ")) + redoCommandName + m_redoAccelerator;
 289         }
 290         else
 291         {
 292             buf = _("&Redo") + m_redoAccelerator;
 293         }
 294     }
 295     else
 296     {
 297         if (m_commands.GetCount() == 0)
 298         {
 299             buf = _("&Redo") + m_redoAccelerator;
 300         }
 301         else
 302         {
 303             // currentCommand is NULL but there are commands: this means that
 304             // we've undone to the start of the list, but can redo the first.
 305             wxCommand *redoCommand = (wxCommand *)m_commands.GetFirst()->GetData();
 306             wxString redoCommandName(redoCommand->GetName());
 307             if (redoCommandName.empty()) redoCommandName = _("Unnamed command");
 308             buf = wxString(_("&Redo ")) + redoCommandName + m_redoAccelerator;
 309         }
 310     }
 311     return buf;
 312 }
 313
 314 void wxCommandProcessor::ClearCommands()
 315 {
 316     wxList::compatibility_iterator node = m_commands.GetFirst();
 317     while (node)
 318     {
 319         wxCommand *command = (wxCommand *)node->GetData();
 320         delete command;
 321         m_commands.Erase(node);
 322         node = m_commands.GetFirst();
 323     }
 324
 325     m_currentCommand = wxList::compatibility_iterator();
 326     m_lastSavedCommand = wxList::compatibility_iterator();
 327 }
 328
 329