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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) wxWindows team
9 // Licence: wxWindows licence
10 ///////////////////////////////////////////////////////////////////////////////
11
12 // ============================================================================
13 // declarations
14 // ============================================================================
15
16 // ----------------------------------------------------------------------------
17 // headers
18 // ----------------------------------------------------------------------------
19
20 #ifdef __GNUG__
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 wxCommand::~wxCommand()
57 {
58 }
59
60 // ----------------------------------------------------------------------------
61 // Command processor
62 // ----------------------------------------------------------------------------
63
64 wxCommandProcessor::wxCommandProcessor(int maxCommands)
65 {
66 m_maxNoCommands = maxCommands;
67 m_currentCommand = (wxNode *) NULL;
68 #if wxUSE_MENUS
69 m_commandEditMenu = (wxMenu *) NULL;
70 #endif // wxUSE_MENUS
71 m_undoAccelerator = wxT("\tCtrl+Z");
72 m_redoAccelerator = wxT("\tCtrl+Y");
73 }
74
75 wxCommandProcessor::~wxCommandProcessor()
76 {
77 ClearCommands();
78 }
79
80 bool wxCommandProcessor::DoCommand(wxCommand& cmd)
81 {
82 return cmd.Do();
83 }
84
85 bool wxCommandProcessor::UndoCommand(wxCommand& cmd)
86 {
87 return cmd.Undo();
88 }
89
90 // Pass a command to the processor. The processor calls Do();
91 // if successful, is appended to the command history unless
92 // storeIt is FALSE.
93 bool wxCommandProcessor::Submit(wxCommand *command, bool storeIt)
94 {
95 wxCHECK_MSG( command, FALSE, _T("no command in wxCommandProcessor::Submit") );
96
97 if ( !DoCommand(*command) )
98 {
99 // the user code expects the command to be deleted anyhow
100 delete command;
101
102 return FALSE;
103 }
104
105 if ( storeIt )
106 Store(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 (m_commands.Number() == m_maxNoCommands)
116 {
117 wxNode *firstNode = m_commands.First();
118 wxCommand *firstCommand = (wxCommand *)firstNode->Data();
119 delete firstCommand;
120 delete firstNode;
121 }
122
123 // Correct a bug: we must chop off the current 'branch'
124 // so that we're at the end of the command list.
125 if (!m_currentCommand)
126 ClearCommands();
127 else
128 {
129 wxNode *node = m_currentCommand->Next();
130 while (node)
131 {
132 wxNode *next = node->Next();
133 delete (wxCommand *)node->Data();
134 delete node;
135 node = next;
136 }
137 }
138
139 m_commands.Append(command);
140 m_currentCommand = m_commands.Last();
141 SetMenuStrings();
142 }
143
144 bool wxCommandProcessor::Undo()
145 {
146 wxCommand *command = GetCurrentCommand();
147 if ( command && command->CanUndo() )
148 {
149 if ( UndoCommand(*command) )
150 {
151 m_currentCommand = m_currentCommand->Previous();
152 SetMenuStrings();
153 return TRUE;
154 }
155 }
156
157 return FALSE;
158 }
159
160 bool wxCommandProcessor::Redo()
161 {
162 wxCommand *redoCommand = (wxCommand *) NULL;
163 wxNode *redoNode = (wxNode *) NULL;
164
165 if ( m_currentCommand )
166 {
167 // is there anything to redo?
168 if ( m_currentCommand->Next() )
169 {
170 redoCommand = (wxCommand *)m_currentCommand->Next()->Data();
171 redoNode = m_currentCommand->Next();
172 }
173 }
174 else // no current command, redo the first one
175 {
176 if (m_commands.Number() > 0)
177 {
178 redoCommand = (wxCommand *)m_commands.First()->Data();
179 redoNode = m_commands.First();
180 }
181 }
182
183 if (redoCommand)
184 {
185 bool success = DoCommand(*redoCommand);
186 if (success)
187 {
188 m_currentCommand = redoNode;
189 SetMenuStrings();
190 return TRUE;
191 }
192 }
193 return FALSE;
194 }
195
196 bool wxCommandProcessor::CanUndo() const
197 {
198 wxCommand *command = GetCurrentCommand();
199
200 return command && command->CanUndo();
201 }
202
203 bool wxCommandProcessor::CanRedo() const
204 {
205 if ((m_currentCommand != (wxNode*) NULL) && (m_currentCommand->Next() == (wxNode*) NULL))
206 return FALSE;
207
208 if ((m_currentCommand != (wxNode*) NULL) && (m_currentCommand->Next() != (wxNode*) NULL))
209 return TRUE;
210
211 if ((m_currentCommand == (wxNode*) NULL) && (m_commands.Number() > 0))
212 return TRUE;
213
214 return FALSE;
215 }
216
217 void wxCommandProcessor::Initialize()
218 {
219 m_currentCommand = m_commands.Last();
220 SetMenuStrings();
221 }
222
223 void wxCommandProcessor::SetMenuStrings()
224 {
225 #if wxUSE_MENUS
226 if (m_commandEditMenu)
227 {
228 wxString buf;
229 if (m_currentCommand)
230 {
231 wxCommand *command = (wxCommand *)m_currentCommand->Data();
232 wxString commandName(command->GetName());
233 if (commandName == wxT("")) commandName = _("Unnamed command");
234 bool canUndo = command->CanUndo();
235 if (canUndo)
236 buf = wxString(_("&Undo ")) + commandName + m_undoAccelerator;
237 else
238 buf = wxString(_("Can't &Undo ")) + commandName + m_undoAccelerator;
239
240 m_commandEditMenu->SetLabel(wxID_UNDO, buf);
241 m_commandEditMenu->Enable(wxID_UNDO, canUndo);
242
243 // We can redo, if we're not at the end of the history.
244 if (m_currentCommand->Next())
245 {
246 wxCommand *redoCommand = (wxCommand *)m_currentCommand->Next()->Data();
247 wxString redoCommandName(redoCommand->GetName());
248 if (redoCommandName == wxT("")) redoCommandName = _("Unnamed command");
249 buf = wxString(_("&Redo ")) + redoCommandName + m_redoAccelerator;
250 m_commandEditMenu->SetLabel(wxID_REDO, buf);
251 m_commandEditMenu->Enable(wxID_REDO, TRUE);
252 }
253 else
254 {
255 m_commandEditMenu->SetLabel(wxID_REDO, _("&Redo") + m_redoAccelerator);
256 m_commandEditMenu->Enable(wxID_REDO, FALSE);
257 }
258 }
259 else
260 {
261 m_commandEditMenu->SetLabel(wxID_UNDO, _("&Undo") + m_undoAccelerator);
262 m_commandEditMenu->Enable(wxID_UNDO, FALSE);
263
264 if (m_commands.Number() == 0)
265 {
266 m_commandEditMenu->SetLabel(wxID_REDO, _("&Redo") + m_redoAccelerator);
267 m_commandEditMenu->Enable(wxID_REDO, FALSE);
268 }
269 else
270 {
271 // currentCommand is NULL but there are commands: this means that
272 // we've undone to the start of the list, but can redo the first.
273 wxCommand *redoCommand = (wxCommand *)m_commands.First()->Data();
274 wxString redoCommandName(redoCommand->GetName());
275 if (redoCommandName == wxT("")) redoCommandName = _("Unnamed command");
276 buf = wxString(_("&Redo ")) + redoCommandName + m_redoAccelerator;
277 m_commandEditMenu->SetLabel(wxID_REDO, buf);
278 m_commandEditMenu->Enable(wxID_REDO, TRUE);
279 }
280 }
281 }
282 #endif // wxUSE_MENUS
283 }
284
285 void wxCommandProcessor::ClearCommands()
286 {
287 wxNode *node = m_commands.First();
288 while (node)
289 {
290 wxCommand *command = (wxCommand *)node->Data();
291 delete command;
292 delete node;
293 node = m_commands.First();
294 }
295 m_currentCommand = (wxNode *) NULL;
296 }
297
298