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[wxWidgets.git] / interface / wx / combo.h
1 /////////////////////////////////////////////////////////////////////////////
2 // Name: combo.h
3 // Purpose: interface of wxComboCtrl and wxComboPopup
4 // Author: wxWidgets team
5 // RCS-ID: $Id$
6 // Licence: wxWindows license
7 /////////////////////////////////////////////////////////////////////////////
8
9 /**
10 @class wxComboPopup
11
12 In order to use a custom popup with wxComboCtrl, an interface class must be
13 derived from wxComboPopup.
14
15 For more information on how to use it, see @ref comboctrl_custompopup.
16
17 @library{wxcore}
18 @category{ctrl}
19
20 @see wxComboCtrl
21 */
22 class wxComboPopup
23 {
24 public:
25 /**
26 Default constructor. It is recommended that internal variables are
27 prepared in Init() instead (because m_combo is not valid in
28 constructor).
29 */
30 wxComboPopup();
31
32 /**
33 The derived class must implement this to create the popup control.
34
35 @return @true if the call succeeded, @false otherwise.
36 */
37 virtual bool Create(wxWindow* parent) = 0;
38
39 /**
40 Utility function that hides the popup.
41 */
42 void Dismiss();
43
44 /**
45 The derived class may implement this to return adjusted size for the
46 popup control, according to the variables given.
47
48 @param minWidth
49 Preferred minimum width.
50 @param prefHeight
51 Preferred height. May be -1 to indicate no preference.
52 @param maxHeight
53 Max height for window, as limited by screen size.
54
55 @remarks This function is called each time popup is about to be shown.
56 */
57 virtual wxSize GetAdjustedSize(int minWidth, int prefHeight, int maxHeight);
58
59 /**
60 The derived class must implement this to return pointer to the
61 associated control created in Create().
62 */
63 virtual wxWindow* GetControl() = 0;
64
65 /**
66 The derived class must implement this to return string representation
67 of the value.
68 */
69 virtual wxString GetStringValue() const = 0;
70
71 /**
72 The derived class must implement this to initialize its internal
73 variables. This method is called immediately after construction
74 finishes. m_combo member variable has been initialized before the call.
75 */
76 virtual void Init();
77
78 /**
79 Utility method that returns @true if Create has been called.
80
81 Useful in conjunction with LazyCreate().
82 */
83 bool IsCreated() const;
84
85 /**
86 The derived class may implement this to return @true if it wants to
87 delay call to Create() until the popup is shown for the first time. It
88 is more efficient, but on the other hand it is often more convenient to
89 have the control created immediately.
90
91 @remarks Base implementation returns @false.
92 */
93 virtual bool LazyCreate();
94
95 /**
96 The derived class may implement this to do something when the parent
97 wxComboCtrl gets double-clicked.
98 */
99 virtual void OnComboDoubleClick();
100
101 /**
102 The derived class may implement this to receive key events from the
103 parent wxComboCtrl.
104
105 Events not handled should be skipped, as usual.
106 */
107 virtual void OnComboKeyEvent(wxKeyEvent& event);
108
109 /**
110 The derived class may implement this to do special processing when
111 popup is hidden.
112 */
113 virtual void OnDismiss();
114
115 /**
116 The derived class may implement this to do special processing when
117 popup is shown.
118 */
119 virtual void OnPopup();
120
121 /**
122 The derived class may implement this to paint the parent wxComboCtrl.
123
124 Default implementation draws value as string.
125 */
126 virtual void PaintComboControl(wxDC& dc, const wxRect& rect);
127
128 /**
129 The derived class must implement this to receive string value changes
130 from wxComboCtrl.
131 */
132 virtual void SetStringValue(const wxString& value);
133
134 /**
135 Parent wxComboCtrl. This is parameter has been prepared before Init()
136 is called.
137 */
138 wxComboCtrl m_combo;
139 };
140
141
142
143 /**
144 Features enabled for wxComboCtrl.
145
146 @see wxComboCtrl::GetFeatures()
147 */
148 struct wxComboCtrlFeatures
149 {
150 enum
151 {
152 MovableButton = 0x0001, ///< Button can be on either side of control.
153 BitmapButton = 0x0002, ///< Button may be replaced with bitmap.
154 ButtonSpacing = 0x0004, ///< Button can have spacing from the edge
155 ///< of the control.
156 TextIndent = 0x0008, ///< wxComboCtrl::SetTextIndent() can be used.
157 PaintControl = 0x0010, ///< Combo control itself can be custom painted.
158 PaintWritable = 0x0020, ///< A variable-width area in front of writable
159 ///< combo control's textctrl can be custom
160 ///< painted.
161 Borderless = 0x0040, ///< wxNO_BORDER window style works.
162
163 All = MovableButton | BitmapButton | ButtonSpacing |
164 TextIndent | PaintControl | PaintWritable |
165 Borderless ///< All features.
166 };
167 };
168
169
170 /**
171 @class wxComboCtrl
172
173 A combo control is a generic combobox that allows totally custom popup. In
174 addition it has other customization features. For instance, position and
175 size of the dropdown button can be changed.
176
177 @section comboctrl_custompopup Setting Custom Popup for wxComboCtrl
178
179 wxComboCtrl needs to be told somehow which control to use and this is done
180 by SetPopupControl(). However, we need something more than just a wxControl
181 in this method as, for example, we need to call
182 SetStringValue("initial text value") and wxControl doesn't have such
183 method. So we also need a wxComboPopup which is an interface which must be
184 implemented by a control to be usable as a popup.
185
186 We couldn't derive wxComboPopup from wxControl as this would make it
187 impossible to have a class deriving from a wxWidgets control and from it,
188 so instead it is just a mix-in.
189
190 Here's a minimal sample of wxListView popup:
191
192 @code
193 #include <wx/combo.h>
194 #include <wx/listctrl.h>
195
196 class wxListViewComboPopup : public wxListView, public wxComboPopup
197 {
198 public:
199 // Initialize member variables
200 virtual void Init()
201 {
202 m_value = -1;
203 }
204
205 // Create popup control
206 virtual bool Create(wxWindow* parent)
207 {
208 return wxListView::Create(parent,1,wxPoint(0,0),wxDefaultSize);
209 }
210
211 // Return pointer to the created control
212 virtual wxWindow *GetControl() { return this; }
213
214 // Translate string into a list selection
215 virtual void SetStringValue(const wxString& s)
216 {
217 int n = wxListView::FindItem(-1,s);
218 if ( n >= 0 && n < wxListView::GetItemCount() )
219 wxListView::Select(n);
220 }
221
222 // Get list selection as a string
223 virtual wxString GetStringValue() const
224 {
225 if ( m_value >= 0 )
226 return wxListView::GetItemText(m_value);
227 return wxEmptyString;
228 }
229
230 // Do mouse hot-tracking (which is typical in list popups)
231 void OnMouseMove(wxMouseEvent& event)
232 {
233 // TODO: Move selection to cursor
234 }
235
236 // On mouse left up, set the value and close the popup
237 void OnMouseClick(wxMouseEvent& WXUNUSED(event))
238 {
239 m_value = wxListView::GetFirstSelected();
240
241 // TODO: Send event as well
242
243 Dismiss();
244 }
245
246 protected:
247
248 int m_value; // current item index
249
250 private:
251 DECLARE_EVENT_TABLE()
252 };
253
254 BEGIN_EVENT_TABLE(wxListViewComboPopup, wxListView)
255 EVT_MOTION(wxListViewComboPopup::OnMouseMove)
256 EVT_LEFT_UP(wxListViewComboPopup::OnMouseClick)
257 END_EVENT_TABLE()
258 @endcode
259
260 Here's how you would create and populate it in a dialog constructor:
261
262 @code
263 wxComboCtrl* comboCtrl = new wxComboCtrl(this, wxID_ANY, wxEmptyString);
264
265 wxListViewComboPopup* popupCtrl = new wxListViewComboPopup();
266
267 // It is important to call SetPopupControl() as soon as possible
268 comboCtrl->SetPopupControl(popupCtrl);
269
270 // Populate using wxListView methods
271 popupCtrl->InsertItem(popupCtrl->GetItemCount(), "First Item");
272 popupCtrl->InsertItem(popupCtrl->GetItemCount(), "Second Item");
273 popupCtrl->InsertItem(popupCtrl->GetItemCount(), "Third Item");
274 @endcode
275
276 @beginStyleTable
277 @style{wxCB_READONLY}
278 Text will not be editable.
279 @style{wxCB_SORT}
280 Sorts the entries in the list alphabetically.
281 @style{wxTE_PROCESS_ENTER}
282 The control will generate the event wxEVT_COMMAND_TEXT_ENTER
283 (otherwise pressing Enter key is either processed internally by the
284 control or used for navigation between dialog controls). Windows
285 only.
286 @style{wxCC_SPECIAL_DCLICK}
287 Double-clicking triggers a call to popup's OnComboDoubleClick.
288 Actual behaviour is defined by a derived class. For instance,
289 wxOwnerDrawnComboBox will cycle an item. This style only applies if
290 wxCB_READONLY is used as well.
291 @style{wxCC_STD_BUTTON}
292 Drop button will behave more like a standard push button.
293 @endStyleTable
294
295 @beginEventTable{wxCommandEvent}
296 @event{EVT_TEXT(id, func)}
297 Process a wxEVT_COMMAND_TEXT_UPDATED event, when the text changes.
298 @event{EVT_TEXT_ENTER(id, func)}
299 Process a wxEVT_COMMAND_TEXT_ENTER event, when RETURN is pressed in
300 the combo control.
301 @endEventTable
302
303 @library{wxbase}
304 @category{ctrl}
305 @appearance{comboctrl.png}
306
307 @see wxComboBox, wxChoice, wxOwnerDrawnComboBox, wxComboPopup,
308 wxCommandEvent
309 */
310 class wxComboCtrl : public wxControl
311 {
312 public:
313 /**
314 Default constructor.
315 */
316 wxComboCtrl();
317
318 /**
319 Constructor, creating and showing a combo control.
320
321 @param parent
322 Parent window. Must not be @NULL.
323 @param id
324 Window identifier. The value wxID_ANY indicates a default value.
325 @param value
326 Initial selection string. An empty string indicates no selection.
327 @param pos
328 Window position.
329 @param size
330 Window size. If wxDefaultSize is specified then the window is sized
331 appropriately.
332 @param style
333 Window style. See wxComboCtrl.
334 @param validator
335 Window validator.
336 @param name
337 Window name.
338
339 @see Create(), wxValidator
340 */
341 wxComboCtrl(wxWindow* parent, wxWindowID id = wxID_ANY,
342 const wxString& value = wxEmptyString,
343 const wxPoint& pos = wxDefaultPosition,
344 const wxSize& size = wxDefaultSize,
345 long style = 0,
346 const wxValidator& validator = wxDefaultValidator,
347 const wxString& name = wxComboBoxNameStr);
348
349 /**
350 Destructor, destroying the combo control.
351 */
352 virtual ~wxComboCtrl();
353
354 /**
355 Copies the selected text to the clipboard.
356 */
357 virtual void Copy();
358
359 /**
360 Creates the combo control for two-step construction. Derived classes
361 should call or replace this function. See wxComboCtrl() for further
362 details.
363 */
364 bool Create(wxWindow* parent, wxWindowID id = wxID_ANY,
365 const wxString& value = wxEmptyString,
366 const wxPoint& pos = wxDefaultPosition,
367 const wxSize& size = wxDefaultSize,
368 long style = 0,
369 const wxValidator& validator = wxDefaultValidator,
370 const wxString& name = wxComboBoxNameStr);
371
372 /**
373 Copies the selected text to the clipboard and removes the selection.
374 */
375 virtual void Cut();
376
377 /**
378 Enables or disables popup animation, if any, depending on the value of
379 the argument.
380 */
381 void EnablePopupAnimation(bool enable = true);
382
383 /**
384 Returns disabled button bitmap that has been set with
385 SetButtonBitmaps().
386
387 @return A reference to the disabled state bitmap.
388 */
389 const wxBitmap& GetBitmapDisabled() const;
390
391 /**
392 Returns button mouse hover bitmap that has been set with
393 SetButtonBitmaps().
394
395 @return A reference to the mouse hover state bitmap.
396 */
397 const wxBitmap& GetBitmapHover() const;
398
399 /**
400 Returns default button bitmap that has been set with
401 SetButtonBitmaps().
402
403 @return A reference to the normal state bitmap.
404 */
405 const wxBitmap& GetBitmapNormal() const;
406
407 /**
408 Returns depressed button bitmap that has been set with
409 SetButtonBitmaps().
410
411 @return A reference to the depressed state bitmap.
412 */
413 const wxBitmap& GetBitmapPressed() const;
414
415 /**
416 Returns current size of the dropdown button.
417 */
418 wxSize GetButtonSize();
419
420 /**
421 Returns custom painted area in control.
422
423 @see SetCustomPaintWidth().
424 */
425 int GetCustomPaintWidth() const;
426
427 /**
428 Returns features supported by wxComboCtrl. If needed feature is
429 missing, you need to instead use wxGenericComboCtrl, which however may
430 lack a native look and feel (but otherwise sports identical API).
431
432 @return Value returned is a combination of the flags defined in
433 wxComboCtrlFeatures.
434 */
435 static int GetFeatures();
436
437 /**
438 Returns the insertion point for the combo control's text field.
439
440 @note Under Windows, this function always returns 0 if the combo
441 control doesn't have the focus.
442 */
443 virtual long GetInsertionPoint() const;
444
445 /**
446 Returns the last position in the combo control text field.
447 */
448 virtual long GetLastPosition() const;
449
450 /**
451 Returns current popup interface that has been set with
452 SetPopupControl().
453 */
454 wxComboPopup* GetPopupControl();
455
456 /**
457 Returns popup window containing the popup control.
458 */
459 wxWindow* GetPopupWindow() const;
460
461 /**
462 Get the text control which is part of the combo control.
463 */
464 wxTextCtrl* GetTextCtrl() const;
465
466 /**
467 Returns actual indentation in pixels.
468 */
469 wxCoord GetTextIndent() const;
470
471 /**
472 Returns area covered by the text field (includes everything except
473 borders and the dropdown button).
474 */
475 const wxRect& GetTextRect() const;
476
477 /**
478 Returns text representation of the current value. For writable combo
479 control it always returns the value in the text field.
480 */
481 virtual wxString GetValue() const;
482
483 /**
484 Dismisses the popup window.
485 */
486 virtual void HidePopup();
487
488 /**
489 Returns @true if the popup is currently shown
490 */
491 bool IsPopupShown() const;
492
493 /**
494 Returns @true if the popup window is in the given state. Possible
495 values are:
496
497 @beginTable
498 @row2col{wxComboCtrl::Hidden, Popup window is hidden.}
499 @row2col{wxComboCtrl::Animating, Popup window is being shown, but the
500 popup animation has not yet finished.}
501 @row2col{wxComboCtrl::Visible, Popup window is fully visible.}
502 @endTable
503 */
504 bool IsPopupWindowState(int state) const;
505
506 /**
507 Implement in a derived class to define what happens on dropdown button
508 click. Default action is to show the popup.
509
510 @note If you implement this to do something else than show the popup,
511 you must then also implement DoSetPopupControl() to always return
512 @NULL.
513 */
514 virtual void OnButtonClick();
515
516 /**
517 Pastes text from the clipboard to the text field.
518 */
519 virtual void Paste();
520
521 /**
522 Removes the text between the two positions in the combo control text
523 field.
524
525 @param from
526 The first position.
527 @param to
528 The last position.
529 */
530 virtual void Remove(long from, long to);
531
532 /**
533 Replaces the text between two positions with the given text, in the
534 combo control text field.
535
536 @param from
537 The first position.
538 @param to
539 The second position.
540 @param text
541 The text to insert.
542 */
543 virtual void Replace(long from, long to, const wxString& text);
544
545 /**
546 Sets custom dropdown button graphics.
547
548 @param bmpNormal
549 Default button image.
550 @param pushButtonBg
551 If @true, blank push button background is painted below the image.
552 @param bmpPressed
553 Depressed button image.
554 @param bmpHover
555 Button image when mouse hovers above it. This should be ignored on
556 platforms and themes that do not generally draw different kind of
557 button on mouse hover.
558 @param bmpDisabled
559 Disabled button image.
560 */
561 void SetButtonBitmaps(const wxBitmap& bmpNormal,
562 bool pushButtonBg = false,
563 const wxBitmap& bmpPressed = wxNullBitmap,
564 const wxBitmap& bmpHover = wxNullBitmap,
565 const wxBitmap& bmpDisabled = wxNullBitmap);
566
567 /**
568 Sets size and position of dropdown button.
569
570 @param width
571 Button width. Value = 0 specifies default.
572 @param height
573 Button height. Value = 0 specifies default.
574 @param side
575 Indicates which side the button will be placed. Value can be wxLEFT
576 or wxRIGHT.
577 @param spacingX
578 Horizontal spacing around the button. Default is 0.
579 */
580 void SetButtonPosition(int width = -1, int height = -1,
581 int side = wxRIGHT, int spacingX = 0);
582
583 /**
584 Set width, in pixels, of custom painted area in control without
585 @c wxCB_READONLY style. In read-only wxOwnerDrawnComboBox, this is used
586 to indicate area that is not covered by the focus rectangle.
587 */
588 void SetCustomPaintWidth(int width);
589
590 /**
591 Sets the insertion point in the text field.
592
593 @param pos
594 The new insertion point.
595 */
596 virtual void SetInsertionPoint(long pos);
597
598 /**
599 Sets the insertion point at the end of the combo control text field.
600 */
601 virtual void SetInsertionPointEnd();
602
603 /**
604 Set side of the control to which the popup will align itself. Valid
605 values are @c wxLEFT, @c wxRIGHT and 0. The default value 0 means that
606 the most appropriate side is used (which, currently, is always
607 @c wxLEFT).
608 */
609 void SetPopupAnchor(int anchorSide);
610
611 /**
612 Set popup interface class derived from wxComboPopup. This method should
613 be called as soon as possible after the control has been created,
614 unless OnButtonClick() has been overridden.
615 */
616 void SetPopupControl(wxComboPopup* popup);
617
618 /**
619 Extends popup size horizontally, relative to the edges of the combo
620 control.
621
622 @param extLeft
623 How many pixel to extend beyond the left edge of the control.
624 Default is 0.
625 @param extRight
626 How many pixel to extend beyond the right edge of the control.
627 Default is 0.
628
629 @remarks Popup minimum width may override arguments. It is up to the
630 popup to fully take this into account.
631 */
632 void SetPopupExtents(int extLeft, int extRight);
633
634 /**
635 Sets preferred maximum height of the popup.
636
637 @remarks Value -1 indicates the default.
638 */
639 void SetPopupMaxHeight(int height);
640
641 /**
642 Sets minimum width of the popup. If wider than combo control, it will
643 extend to the left.
644
645 @remarks Value -1 indicates the default. Also, popup implementation may
646 choose to ignore this.
647 */
648 void SetPopupMinWidth(int width);
649
650 /**
651 Selects the text between the two positions, in the combo control text
652 field.
653
654 @param from
655 The first position.
656 @param to
657 The second position.
658 */
659 virtual void SetSelection(long from, long to);
660
661 /**
662 Sets the text for the text field without affecting the popup. Thus,
663 unlike SetValue(), it works equally well with combo control using
664 @c wxCB_READONLY style.
665 */
666 void SetText(const wxString& value);
667
668 /**
669 This will set the space in pixels between left edge of the control and
670 the text, regardless whether control is read-only or not. Value -1 can
671 be given to indicate platform default.
672 */
673 void SetTextIndent(int indent);
674
675 /**
676 Sets the text for the combo control text field.
677
678 @note For a combo control with @c wxCB_READONLY style the string must
679 be accepted by the popup (for instance, exist in the dropdown
680 list), otherwise the call to SetValue() is ignored.
681 */
682 virtual void SetValue(const wxString& value);
683
684 /**
685 Same as SetValue(), but also sends wxCommandEvent of type
686 wxEVT_COMMAND_TEXT_UPDATED if @a withEvent is @true.
687 */
688 void SetValueWithEvent(const wxString& value, bool withEvent = true);
689
690 /**
691 Show the popup.
692 */
693 virtual void ShowPopup();
694
695 /**
696 Undoes the last edit in the text field. Windows only.
697 */
698 virtual void Undo();
699
700 /**
701 Enable or disable usage of an alternative popup window, which
702 guarantees ability to focus the popup control, and allows common native
703 controls to function normally. This alternative popup window is usually
704 a wxDialog, and as such, when it is shown, its parent top-level window
705 will appear as if the focus has been lost from it.
706 */
707 void UseAltPopupWindow(bool enable = true);
708
709 protected:
710
711 /**
712 This member function is not normally called in application code.
713 Instead, it can be implemented in a derived class to create a custom
714 popup animation.
715
716 The parameters are the same as those for DoShowPopup().
717
718 @return @true if animation finishes before the function returns,
719 @false otherwise. In the latter case you need to manually call
720 DoShowPopup() after the animation ends.
721 */
722 virtual bool AnimateShow(const wxRect& rect, int flags);
723
724 /**
725 This member function is not normally called in application code.
726 Instead, it can be implemented in a derived class to return default
727 wxComboPopup, incase @a popup is @NULL.
728
729 @note If you have implemented OnButtonClick() to do something else than
730 show the popup, then DoSetPopupControl() must always set @a popup
731 to @NULL.
732 */
733 virtual void DoSetPopupControl(wxComboPopup* popup);
734
735 /**
736 This member function is not normally called in application code.
737 Instead, it must be called in a derived class to make sure popup is
738 properly shown after a popup animation has finished (but only if
739 AnimateShow() did not finish the animation within its function scope).
740
741 @param rect
742 Position to show the popup window at, in screen coordinates.
743 @param flags
744 Combination of any of the following:
745 @beginTable
746 @row2col{wxComboCtrl::ShowAbove,
747 Popup is shown above the control instead of below.}
748 @row2col{wxComboCtrl::CanDeferShow,
749 Showing the popup can be deferred to happen sometime after
750 ShowPopup() has finished. In this case, AnimateShow() must
751 return false.}
752 @endTable
753 */
754 virtual void DoShowPopup(const wxRect& rect, int flags);
755 };
756