Calculate ellipsized width exactly.
[wxWidgets.git] / src / common / ctrlcmn.cpp
1 /////////////////////////////////////////////////////////////////////////////
2 // Name: src/common/ctrlcmn.cpp
3 // Purpose: wxControl common interface
4 // Author: Vadim Zeitlin
5 // Modified by:
6 // Created: 26.07.99
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 // For compilers that support precompilation, includes "wx.h".
21 #include "wx/wxprec.h"
22
23 #ifdef __BORLANDC__
24 #pragma hdrstop
25 #endif
26
27 #if wxUSE_CONTROLS
28
29 #include "wx/control.h"
30
31 #ifndef WX_PRECOMP
32 #include "wx/dc.h"
33 #include "wx/log.h"
34 #include "wx/radiobut.h"
35 #include "wx/statbmp.h"
36 #include "wx/bitmap.h"
37 #include "wx/utils.h" // for wxStripMenuCodes()
38 #include "wx/settings.h"
39 #endif
40
41 const char wxControlNameStr[] = "control";
42
43 // ============================================================================
44 // implementation
45 // ============================================================================
46
47 wxControlBase::~wxControlBase()
48 {
49 // this destructor is required for Darwin
50 }
51
52 bool wxControlBase::Create(wxWindow *parent,
53 wxWindowID id,
54 const wxPoint &pos,
55 const wxSize &size,
56 long style,
57 const wxValidator& wxVALIDATOR_PARAM(validator),
58 const wxString &name)
59 {
60 bool ret = wxWindow::Create(parent, id, pos, size, style, name);
61
62 #if wxUSE_VALIDATORS
63 if ( ret )
64 SetValidator(validator);
65 #endif // wxUSE_VALIDATORS
66
67 return ret;
68 }
69
70 bool wxControlBase::CreateControl(wxWindowBase *parent,
71 wxWindowID id,
72 const wxPoint& pos,
73 const wxSize& size,
74 long style,
75 const wxValidator& validator,
76 const wxString& name)
77 {
78 // even if it's possible to create controls without parents in some port,
79 // it should surely be discouraged because it doesn't work at all under
80 // Windows
81 wxCHECK_MSG( parent, false, wxT("all controls must have parents") );
82
83 if ( !CreateBase(parent, id, pos, size, style, validator, name) )
84 return false;
85
86 parent->AddChild(this);
87
88 return true;
89 }
90
91 void wxControlBase::Command(wxCommandEvent& event)
92 {
93 (void)GetEventHandler()->ProcessEvent(event);
94 }
95
96 void wxControlBase::InitCommandEvent(wxCommandEvent& event) const
97 {
98 event.SetEventObject(const_cast<wxControlBase *>(this));
99
100 // event.SetId(GetId()); -- this is usuall done in the event ctor
101
102 switch ( m_clientDataType )
103 {
104 case wxClientData_Void:
105 event.SetClientData(GetClientData());
106 break;
107
108 case wxClientData_Object:
109 event.SetClientObject(GetClientObject());
110 break;
111
112 case wxClientData_None:
113 // nothing to do
114 ;
115 }
116 }
117
118 bool wxControlBase::SetFont(const wxFont& font)
119 {
120 InvalidateBestSize();
121 return wxWindow::SetFont(font);
122 }
123
124 // wxControl-specific processing after processing the update event
125 void wxControlBase::DoUpdateWindowUI(wxUpdateUIEvent& event)
126 {
127 // call inherited
128 wxWindowBase::DoUpdateWindowUI(event);
129
130 // update label
131 if ( event.GetSetText() )
132 {
133 if ( event.GetText() != GetLabel() )
134 SetLabel(event.GetText());
135 }
136
137 // Unfortunately we don't yet have common base class for
138 // wxRadioButton, so we handle updates of radiobuttons here.
139 // TODO: If once wxRadioButtonBase will exist, move this code there.
140 #if wxUSE_RADIOBTN
141 if ( event.GetSetChecked() )
142 {
143 wxRadioButton *radiobtn = wxDynamicCastThis(wxRadioButton);
144 if ( radiobtn )
145 radiobtn->SetValue(event.GetChecked());
146 }
147 #endif // wxUSE_RADIOBTN
148 }
149
150 /* static */
151 wxString wxControlBase::GetLabelText(const wxString& label)
152 {
153 // we don't want strip the TABs here, just the mnemonics
154 return wxStripMenuCodes(label, wxStrip_Mnemonics);
155 }
156
157 /* static */
158 wxString wxControlBase::RemoveMnemonics(const wxString& str)
159 {
160 // we don't want strip the TABs here, just the mnemonics
161 return wxStripMenuCodes(str, wxStrip_Mnemonics);
162 }
163
164 /* static */
165 wxString wxControlBase::EscapeMnemonics(const wxString& text)
166 {
167 wxString label(text);
168 label.Replace("&", "&&");
169 return label;
170 }
171
172 /* static */
173 int wxControlBase::FindAccelIndex(const wxString& label, wxString *labelOnly)
174 {
175 // the character following MNEMONIC_PREFIX is the accelerator for this
176 // control unless it is MNEMONIC_PREFIX too - this allows to insert
177 // literal MNEMONIC_PREFIX chars into the label
178 static const wxChar MNEMONIC_PREFIX = wxT('&');
179
180 if ( labelOnly )
181 {
182 labelOnly->Empty();
183 labelOnly->Alloc(label.length());
184 }
185
186 int indexAccel = -1;
187 for ( wxString::const_iterator pc = label.begin(); pc != label.end(); ++pc )
188 {
189 if ( *pc == MNEMONIC_PREFIX )
190 {
191 ++pc; // skip it
192 if ( pc == label.end() )
193 break;
194 else if ( *pc != MNEMONIC_PREFIX )
195 {
196 if ( indexAccel == -1 )
197 {
198 // remember it (-1 is for MNEMONIC_PREFIX itself
199 indexAccel = pc - label.begin() - 1;
200 }
201 else
202 {
203 wxFAIL_MSG(wxT("duplicate accel char in control label"));
204 }
205 }
206 }
207
208 if ( labelOnly )
209 {
210 *labelOnly += *pc;
211 }
212 }
213
214 return indexAccel;
215 }
216
217 wxBorder wxControlBase::GetDefaultBorder() const
218 {
219 return wxBORDER_THEME;
220 }
221
222 /* static */ wxVisualAttributes
223 wxControlBase::GetCompositeControlsDefaultAttributes(wxWindowVariant WXUNUSED(variant))
224 {
225 wxVisualAttributes attrs;
226 attrs.font = wxSystemSettings::GetFont(wxSYS_DEFAULT_GUI_FONT);
227 attrs.colFg = wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOWTEXT);
228 attrs.colBg = wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOW);
229
230 return attrs;
231 }
232
233 // ----------------------------------------------------------------------------
234 // wxControlBase - ellipsization code
235 // ----------------------------------------------------------------------------
236
237 #define wxELLIPSE_REPLACEMENT wxS("...")
238
239 namespace
240 {
241
242 struct EllipsizeCalculator
243 {
244 EllipsizeCalculator(const wxString& s, const wxDC& dc,
245 int maxFinalWidthPx, int replacementWidthPx)
246 :
247 m_initialCharToRemove(0),
248 m_nCharsToRemove(0),
249 m_outputNeedsUpdate(true),
250 m_str(s),
251 m_dc(dc),
252 m_maxFinalWidthPx(maxFinalWidthPx),
253 m_replacementWidthPx(replacementWidthPx)
254 {
255 m_isOk = dc.GetPartialTextExtents(s, m_charOffsetsPx);
256 wxASSERT( m_charOffsetsPx.GetCount() == s.length() );
257 }
258
259 bool IsOk() const { return m_isOk; }
260
261 bool EllipsizationNotNeeded() const
262 {
263 // NOTE: charOffsetsPx[n] is the width in pixels of the first n characters (with the last one INCLUDED)
264 // thus charOffsetsPx[len-1] is the total width of the string
265 return m_charOffsetsPx.Last() <= m_maxFinalWidthPx;
266 }
267
268 void Init(size_t initialCharToRemove, size_t nCharsToRemove)
269 {
270 m_initialCharToRemove = initialCharToRemove;
271 m_nCharsToRemove = nCharsToRemove;
272 }
273
274 void RemoveFromEnd()
275 {
276 m_nCharsToRemove++;
277 }
278
279 void RemoveFromStart()
280 {
281 m_initialCharToRemove--;
282 m_nCharsToRemove++;
283 }
284
285 size_t GetFirstRemoved() const { return m_initialCharToRemove; }
286 size_t GetLastRemoved() const { return m_initialCharToRemove + m_nCharsToRemove - 1; }
287
288 const wxString& GetEllipsizedText()
289 {
290 if ( m_outputNeedsUpdate )
291 {
292 wxASSERT(m_initialCharToRemove <= m_str.length() - 1); // see valid range for initialCharToRemove above
293 wxASSERT(m_nCharsToRemove >= 1 && m_nCharsToRemove <= m_str.length() - m_initialCharToRemove); // see valid range for nCharsToRemove above
294
295 // erase m_nCharsToRemove characters after m_initialCharToRemove (included);
296 // e.g. if we have the string "foobar" (len = 6)
297 // ^
298 // \--- m_initialCharToRemove = 2
299 // and m_nCharsToRemove = 2, then we get "foar"
300 m_output = m_str;
301 m_output.replace(m_initialCharToRemove, m_nCharsToRemove, wxELLIPSE_REPLACEMENT);
302 }
303
304 return m_output;
305 }
306
307 bool IsShortEnough()
308 {
309 if ( m_nCharsToRemove == m_str.length() )
310 return true; // that's the best we could do
311
312 // Width calculation using partial extents is just an inaccurate
313 // estimate: partial extents have sub-pixel precision and are rounded
314 // by GetPartialTextExtents(); replacing part of the string with "..."
315 // may change them too thanks to changes in ligatures, kerning etc.
316 //
317 // The correct algorithm would be to call GetTextExtent() in every step
318 // of ellipsization, but that would be too expensive, especially when
319 // the difference is just a few pixels. So we use partial extents to
320 // estimate string width and only verify it with GetTextExtent() when
321 // it looks good.
322
323 int estimatedWidth = m_replacementWidthPx; // length of "..."
324
325 // length of text before the removed part:
326 if ( m_initialCharToRemove > 0 )
327 estimatedWidth += m_charOffsetsPx[m_initialCharToRemove - 1];
328
329 // length of text after the removed part:
330
331 if ( GetLastRemoved() < m_str.length() )
332 estimatedWidth += m_charOffsetsPx.Last() - m_charOffsetsPx[GetLastRemoved()];
333
334 if ( estimatedWidth > m_maxFinalWidthPx )
335 return false;
336
337 return m_dc.GetTextExtent(GetEllipsizedText()).GetWidth() <= m_maxFinalWidthPx;
338 }
339
340 // calculation state:
341
342 // REMEMBER: indexes inside the string have a valid range of [0;len-1] if not otherwise constrained
343 // lengths/counts of characters (e.g. nCharsToRemove) have a
344 // valid range of [0;len] if not otherwise constrained
345 // NOTE: since this point we know we have for sure a non-empty string from which we need
346 // to remove _at least_ one character (thus nCharsToRemove below is constrained to be >= 1)
347
348 // index of first character to erase, valid range is [0;len-1]:
349 size_t m_initialCharToRemove;
350 // how many chars do we need to erase? valid range is [0;len-m_initialCharToRemove]
351 size_t m_nCharsToRemove;
352
353 wxString m_output;
354 bool m_outputNeedsUpdate;
355
356 // inputs:
357 wxString m_str;
358 const wxDC& m_dc;
359 int m_maxFinalWidthPx;
360 int m_replacementWidthPx;
361 wxArrayInt m_charOffsetsPx;
362
363 bool m_isOk;
364 };
365
366 } // anonymous namespace
367
368 /* static and protected */
369 wxString wxControlBase::DoEllipsizeSingleLine(const wxString& curLine, const wxDC& dc,
370 wxEllipsizeMode mode, int maxFinalWidthPx,
371 int replacementWidthPx)
372 {
373 wxASSERT_MSG(replacementWidthPx > 0, "Invalid parameters");
374 wxASSERT_LEVEL_2_MSG(!curLine.Contains('\n'),
375 "Use Ellipsize() instead!");
376
377 wxASSERT_MSG( mode != wxELLIPSIZE_NONE, "shouldn't be called at all then" );
378
379 // NOTE: this function assumes that any mnemonic/tab character has already
380 // been handled if it was necessary to handle them (see Ellipsize())
381
382 if (maxFinalWidthPx <= 0)
383 return wxEmptyString;
384
385 size_t len = curLine.length();
386 if (len <= 1 )
387 return curLine;
388
389 EllipsizeCalculator calc(curLine, dc, maxFinalWidthPx, replacementWidthPx);
390
391 if ( !calc.IsOk() )
392 return curLine;
393
394 if ( calc.EllipsizationNotNeeded() )
395 return curLine;
396
397 // let's compute the range of characters to remove depending on the ellipsization mode:
398 switch (mode)
399 {
400 case wxELLIPSIZE_START:
401 {
402 calc.Init(0, 1);
403 while ( !calc.IsShortEnough() )
404 calc.RemoveFromEnd();
405 break;
406 }
407
408 case wxELLIPSIZE_MIDDLE:
409 {
410 // NOTE: the following piece of code works also when len == 1
411
412 // start the removal process from the middle of the string
413 // i.e. separe the string in three parts:
414 // - the first one to preserve, valid range [0;initialCharToRemove-1] or the empty range if initialCharToRemove==0
415 // - the second one to remove, valid range [initialCharToRemove;endCharToRemove]
416 // - the third one to preserve, valid range [endCharToRemove+1;len-1] or the empty range if endCharToRemove==len-1
417 // NOTE: empty range != range [0;0] since the range [0;0] contains 1 character (the zero-th one)!
418
419 calc.Init(len/2, 0);
420
421 bool removeFromStart = true;
422
423 while ( !calc.IsShortEnough() )
424 {
425 const bool canRemoveFromStart = calc.GetFirstRemoved() > 0;
426 const bool canRemoveFromEnd = calc.GetLastRemoved() < len - 1;
427
428 if ( !canRemoveFromStart && !canRemoveFromEnd )
429 {
430 // we need to remove all the characters of the string!
431 break;
432 }
433
434 // Remove from the beginning in even steps and from the end
435 // in odd steps, unless we exhausted one side already:
436 removeFromStart = !removeFromStart;
437 if ( removeFromStart && !canRemoveFromStart )
438 removeFromStart = false;
439 else if ( !removeFromStart && !canRemoveFromEnd )
440 removeFromStart = true;
441
442 if ( removeFromStart )
443 calc.RemoveFromStart();
444 else
445 calc.RemoveFromEnd();
446 }
447 }
448 break;
449
450 case wxELLIPSIZE_END:
451 {
452 calc.Init(len - 1, 1);
453 while ( !calc.IsShortEnough() )
454 calc.RemoveFromStart();
455 break;
456 }
457
458 case wxELLIPSIZE_NONE:
459 default:
460 wxFAIL_MSG("invalid ellipsize mode");
461 return curLine;
462 }
463
464 return calc.GetEllipsizedText();
465 }
466
467 /* static */
468 wxString wxControlBase::Ellipsize(const wxString& label, const wxDC& dc,
469 wxEllipsizeMode mode, int maxFinalWidth,
470 int flags)
471 {
472 wxString ret;
473
474 // these cannot be cached between different Ellipsize() calls as they can
475 // change because of e.g. a font change; however we calculate them only once
476 // when ellipsizing multiline labels:
477 int replacementWidth = dc.GetTextExtent(wxELLIPSE_REPLACEMENT).GetWidth();
478
479 // NB: we must handle correctly labels with newlines:
480 wxString curLine;
481 for ( wxString::const_iterator pc = label.begin(); ; ++pc )
482 {
483 if ( pc == label.end() || *pc == wxS('\n') )
484 {
485 curLine = DoEllipsizeSingleLine(curLine, dc, mode, maxFinalWidth,
486 replacementWidth);
487
488 // add this (ellipsized) row to the rest of the label
489 ret << curLine;
490 if ( pc == label.end() )
491 {
492 // NOTE: this is the return which always exits the function
493 return ret;
494 }
495 else
496 {
497 ret << *pc;
498 curLine.clear();
499 }
500 }
501 // we need to remove mnemonics from the label for correct calculations
502 else if ( *pc == wxS('&') && (flags & wxELLIPSIZE_FLAGS_PROCESS_MNEMONICS) )
503 {
504 // pc+1 is safe: at worst we'll be at end()
505 wxString::const_iterator next = pc + 1;
506 if ( next != label.end() && *next == wxS('&') )
507 curLine += wxS('&'); // && becomes &
508 //else: remove this ampersand
509 }
510 // we need also to expand tabs to properly calc their size
511 else if ( *pc == wxS('\t') && (flags & wxELLIPSIZE_FLAGS_EXPAND_TABS) )
512 {
513 // Windows natively expands the TABs to 6 spaces. Do the same:
514 curLine += wxS(" ");
515 }
516 else
517 {
518 curLine += *pc;
519 }
520 }
521
522 // this return would generate a
523 // warning C4702: unreachable code
524 // with MSVC since the function always exits from inside the loop
525 //return ret;
526 }
527
528
529
530 // ----------------------------------------------------------------------------
531 // wxStaticBitmap
532 // ----------------------------------------------------------------------------
533
534 #if wxUSE_STATBMP
535
536 wxStaticBitmapBase::~wxStaticBitmapBase()
537 {
538 // this destructor is required for Darwin
539 }
540
541 wxSize wxStaticBitmapBase::DoGetBestSize() const
542 {
543 wxSize best;
544 wxBitmap bmp = GetBitmap();
545 if ( bmp.Ok() )
546 best = wxSize(bmp.GetWidth(), bmp.GetHeight());
547 else
548 // this is completely arbitrary
549 best = wxSize(16, 16);
550 CacheBestSize(best);
551 return best;
552 }
553
554 #endif // wxUSE_STATBMP
555
556 #endif // wxUSE_CONTROLS