Document that images in buttons and menus might not be shown under GTK.
[wxWidgets.git] / interface / wx / button.h
1 /////////////////////////////////////////////////////////////////////////////
2 // Name: button.h
3 // Purpose: interface of wxButton
4 // Author: wxWidgets team
5 // RCS-ID: $Id$
6 // Licence: wxWindows license
7 /////////////////////////////////////////////////////////////////////////////
8
9 /**
10 @class wxButton
11
12 A button is a control that contains a text string, and is one of the most
13 common elements of a GUI.
14
15 It may be placed on a @ref wxDialog "dialog box" or on a @ref wxPanel panel,
16 or indeed on almost any other window.
17
18 @beginStyleTable
19 @style{wxBU_LEFT}
20 Left-justifies the label. Windows and GTK+ only.
21 @style{wxBU_TOP}
22 Aligns the label to the top of the button. Windows and GTK+ only.
23 @style{wxBU_RIGHT}
24 Right-justifies the bitmap label. Windows and GTK+ only.
25 @style{wxBU_BOTTOM}
26 Aligns the label to the bottom of the button. Windows and GTK+ only.
27 @style{wxBU_EXACTFIT}
28 Creates the button as small as possible instead of making it of the
29 standard size (which is the default behaviour ).
30 @style{wxBU_NOTEXT}
31 Disables the display of the text label in the button even if it has one
32 or its id is one of the standard stock ids with an associated label:
33 without using this style a button which is only supposed to show a
34 bitmap but uses a standard id would display a label too.
35 @style{wxBORDER_NONE}
36 Creates a button without border. This is currently implemented in MSW,
37 GTK2 and OSX/Carbon ports but in the latter only applies to buttons
38 with bitmaps and using bitmap of one of the standard sizes only, namely
39 128*128, 48*48, 24*24 or 16*16. In all the other cases wxBORDER_NONE is
40 ignored under OSX.
41 @endStyleTable
42
43 By default, i.e. if none of the alignment styles are specified, the label
44 is centered both horizontally and vertically. If the button has both a
45 label and a bitmap, the alignment styles above specify the location of the
46 rectangle combining both the label and the bitmap and the bitmap position
47 set with wxButton::SetBitmapPosition() defines the relative position of the
48 bitmap with respect to the label (however currently non-default alignment
49 combinations are not implemented on all platforms).
50
51 @beginEventEmissionTable{wxCommandEvent}
52 @event{EVT_BUTTON(id, func)}
53 Process a wxEVT_COMMAND_BUTTON_CLICKED event, when the button is clicked.
54 @endEventTable
55
56
57 Since version 2.9.1 wxButton supports showing both text and an image
58 (currently only when using wxMSW, wxGTK or wxOSX/Cocoa ports), see
59 SetBitmap() and SetBitmapLabel(), SetBitmapDisabled() &c methods. In the
60 previous wxWidgets versions this functionality was only available in (the
61 now trivial) wxBitmapButton class which was only capable of showing an
62 image without text.
63
64 A button may have either a single image for all states or different images
65 for the following states (different images are not currently supported
66 under OS X where the normal image is used for all states):
67 @li @b normal: the default state
68 @li @b disabled: bitmap shown when the button is disabled.
69 @li @b pressed: bitmap shown when the button is pushed (e.g. while the user
70 keeps the mouse button pressed on it)
71 @li @b focus: bitmap shown when the button has keyboard focus (but is not
72 pressed as in this case the button is in the pressed state)
73 @li @b current: bitmap shown when the mouse is over the button (but it is
74 not pressed although it may have focus). Notice that if current bitmap
75 is not specified but the current platform UI uses hover images for the
76 buttons (such as Windows XP or GTK+), then the focus bitmap is used for
77 hover state as well. This makes it possible to set focus bitmap only to
78 get reasonably good behaviour on all platforms.
79
80 All of the bitmaps must be of the same size and the normal bitmap must be
81 set first (to a valid bitmap), before setting any other ones.
82
83 The position of the image inside the button be configured using
84 SetBitmapPosition(). By default the image is on the left of the text.
85
86 Please also notice that GTK+ uses a global setting called @c
87 gtk-button-images to determine if the images should be shown in the buttons
88 at all. If it is off (which is the case in e.g. Gnome 2.28 by default), no
89 images will be shown, consistently with the native behaviour.
90
91 @library{wxcore}
92 @category{ctrl}
93 @appearance{button.png}
94
95 @see wxBitmapButton
96 */
97 class wxButton : public wxControl
98 {
99 public:
100 /**
101 Default ctor.
102 */
103 wxButton();
104
105 /**
106 Constructor, creating and showing a button.
107
108 The preferred way to create standard buttons is to use default value of
109 @a label. If no label is supplied and @a id is one of standard IDs from
110 @ref page_stockitems "this list", a standard label will be used.
111
112 In addition to that, the button will be decorated with stock icons under GTK+ 2.
113
114 @param parent
115 Parent window. Must not be @NULL.
116 @param id
117 Button identifier. A value of wxID_ANY indicates a default value.
118 @param label
119 Text to be displayed on the button.
120 @param pos
121 Button position.
122 @param size
123 Button size. If the default size is specified then the button is sized
124 appropriately for the text.
125 @param style
126 Window style. See wxButton class description.
127 @param validator
128 Window validator.
129 @param name
130 Window name.
131
132 @see Create(), wxValidator
133 */
134 wxButton(wxWindow* parent, wxWindowID id,
135 const wxString& label = wxEmptyString,
136 const wxPoint& pos = wxDefaultPosition,
137 const wxSize& size = wxDefaultSize,
138 long style = 0,
139 const wxValidator& validator = wxDefaultValidator,
140 const wxString& name = wxButtonNameStr);
141
142 /**
143 Button creation function for two-step creation.
144 For more details, see wxButton().
145 */
146 bool Create(wxWindow* parent, wxWindowID id,
147 const wxString& label = wxEmptyString,
148 const wxPoint& pos = wxDefaultPosition,
149 const wxSize& size = wxDefaultSize,
150 long style = 0,
151 const wxValidator& validator = wxDefaultValidator,
152 const wxString& name = wxButtonNameStr);
153
154 /**
155 Returns @true if an authentication needed symbol is displayed on the
156 button.
157
158 @remarks This method always returns @false if the platform is not
159 Windows Vista or newer.
160
161 @see SetAuthNeeded()
162
163 @since 2.9.1
164 */
165 bool GetAuthNeeded() const;
166
167 /**
168 Return the bitmap shown by the button.
169
170 The returned bitmap may be invalid only if the button doesn't show any
171 images.
172
173 @see SetBitmap()
174
175 @since 2.9.1
176 */
177 wxBitmap GetBitmap() const;
178
179 /**
180 Returns the bitmap used when the mouse is over the button, which may be
181 invalid.
182
183 @see SetBitmapCurrent()
184
185 @since 2.9.1 (available as wxBitmapButton::GetBitmapHover() in previous
186 versions)
187 */
188 wxBitmap GetBitmapCurrent() const;
189
190 /**
191 Returns the bitmap for the disabled state, which may be invalid.
192
193 @see SetBitmapDisabled()
194
195 @since 2.9.1 (available in wxBitmapButton only in previous versions)
196 */
197 wxBitmap GetBitmapDisabled() const;
198
199 /**
200 Returns the bitmap for the focused state, which may be invalid.
201
202 @see SetBitmapFocus()
203
204 @since 2.9.1 (available in wxBitmapButton only in previous versions)
205 */
206 wxBitmap GetBitmapFocus() const;
207
208 /**
209 Returns the bitmap for the normal state.
210
211 This is exactly the same as GetBitmap() but uses a name
212 backwards-compatible with wxBitmapButton.
213
214 @see SetBitmap(), SetBitmapLabel()
215
216 @since 2.9.1 (available in wxBitmapButton only in previous versions)
217 */
218 wxBitmap GetBitmapLabel() const;
219
220 /**
221 Returns the bitmap for the pressed state, which may be invalid.
222
223 @see SetBitmapPressed()
224
225 @since 2.9.1 (available as wxBitmapButton::GetBitmapSelected() in
226 previous versions)
227 */
228 wxBitmap GetBitmapPressed() const;
229
230 /**
231 Get the margins between the bitmap and the text of the button.
232
233 @see SetBitmapMargins()
234
235 @since 2.9.1
236 */
237 wxSize GetBitmapMargins();
238
239 /**
240 Returns the default size for the buttons. It is advised to make all the dialog
241 buttons of the same size and this function allows to retrieve the (platform and
242 current font dependent size) which should be the best suited for this.
243 */
244 static wxSize GetDefaultSize();
245
246 /**
247 Returns the string label for the button.
248
249 @see SetLabel()
250 */
251 wxString GetLabel() const;
252
253 /**
254 Sets whether an authentication needed symbol should be displayed on the
255 button.
256
257 @remarks This method doesn't do anything if the platform is not Windows
258 Vista or newer.
259
260 @see GetAuthNeeded()
261
262 @since 2.9.1
263 */
264 void SetAuthNeeded(bool needed = true);
265
266 /**
267 Sets the bitmap to display in the button.
268
269 The bitmap is displayed together with the button label. This method
270 sets up a single bitmap which is used in all button states, use
271 SetBitmapDisabled(), SetBitmapPressed(), SetBitmapCurrent() or
272 SetBitmapFocus() to change the individual images used in different
273 states.
274
275 @param bitmap
276 The bitmap to display in the button. May be invalid to remove any
277 currently displayed bitmap.
278 @param dir
279 The position of the bitmap inside the button. By default it is
280 positioned to the left of the text, near to the left button border.
281 Other possible values include wxRIGHT, wxTOP and wxBOTTOM.
282
283 @see SetBitmapPosition(), SetBitmapMargins()
284
285 @since 2.9.1
286 */
287 void SetBitmap(const wxBitmap& bitmap, wxDirection dir = wxLEFT);
288
289 /**
290 Sets the bitmap to be shown when the mouse is over the button.
291
292 @see GetBitmapCurrent()
293
294 @since 2.9.1 (available as wxBitmapButton::SetBitmapHover() in previous
295 versions)
296 */
297 void SetBitmapCurrent(const wxBitmap& bitmap);
298
299 /**
300 Sets the bitmap for the disabled button appearance.
301
302 @see GetBitmapDisabled(), SetBitmapLabel(),
303 SetBitmapPressed(), SetBitmapFocus()
304
305 @since 2.9.1 (available in wxBitmapButton only in previous versions)
306 */
307 void SetBitmapDisabled(const wxBitmap& bitmap);
308
309 /**
310 Sets the bitmap for the button appearance when it has the keyboard
311 focus.
312
313 @see GetBitmapFocus(), SetBitmapLabel(),
314 SetBitmapPressed(), SetBitmapDisabled()
315
316 @since 2.9.1 (available in wxBitmapButton only in previous versions)
317 */
318 void SetBitmapFocus(const wxBitmap& bitmap);
319
320 /**
321 Sets the bitmap label for the button.
322
323 @remarks This is the bitmap used for the unselected state, and for all
324 other states if no other bitmaps are provided.
325
326 @see SetBitmap(), GetBitmapLabel()
327
328 @since 2.9.1 (available in wxBitmapButton only in previous versions)
329 */
330 void SetBitmapLabel(const wxBitmap& bitmap);
331
332 /**
333 Sets the bitmap for the selected (depressed) button appearance.
334
335 @since 2.9.1 (available as wxBitmapButton::SetBitmapSelected() in
336 previous versions)
337 */
338 void SetBitmapPressed(const wxBitmap& bitmap);
339
340 /**
341 Set the margins between the bitmap and the text of the button.
342
343 This method is currently only implemented under MSW. If it is not
344 called, default margin is used around the bitmap.
345
346 @see SetBitmap(), SetBitmapPosition()
347
348 @since 2.9.1
349 */
350 //@{
351 void SetBitmapMargins(wxCoord x, wxCoord y);
352 void SetBitmapMargins(const wxSize& sz);
353 //@}
354
355 /**
356 Set the position at which the bitmap is displayed.
357
358 This method should only be called if the button does have an associated
359 bitmap.
360
361 @since 2.9.1
362
363 @param dir
364 Direction in which the bitmap should be positioned, one of wxLEFT,
365 wxRIGHT, wxTOP or wxBOTTOM.
366 */
367 void SetBitmapPosition(wxDirection dir);
368
369 /**
370 This sets the button to be the default item in its top-level window
371 (e.g. the panel or the dialog box containing it).
372
373 As normal, pressing return causes the default button to be depressed when
374 the return key is pressed.
375
376 See also wxWindow::SetFocus() which sets the keyboard focus for windows
377 and text panel items, and wxTopLevelWindow::SetDefaultItem().
378
379 @remarks Under Windows, only dialog box buttons respond to this function.
380
381 @return the old default item (possibly NULL)
382 */
383 virtual wxWindow* SetDefault();
384
385 /**
386 Sets the string label for the button.
387
388 @param label
389 The label to set.
390 */
391 void SetLabel(const wxString& label);
392 };
393