Expand wxString overview and document some problems due to its dual nature.
[wxWidgets.git] / interface / wx / cursor.h
1 /////////////////////////////////////////////////////////////////////////////
2 // Name: cursor.h
3 // Purpose: interface of wxCursor
4 // Author: wxWidgets team
5 // RCS-ID: $Id$
6 // Licence: wxWindows licence
7 /////////////////////////////////////////////////////////////////////////////
8
9 /**
10 @class wxCursor
11
12 A cursor is a small bitmap usually used for denoting where the mouse
13 pointer is, with a picture that might indicate the interpretation of a
14 mouse click. As with icons, cursors in X and MS Windows are created in a
15 different manner. Therefore, separate cursors will be created for the
16 different environments. Platform-specific methods for creating a wxCursor
17 object are catered for, and this is an occasion where conditional
18 compilation will probably be required (see wxIcon for an example).
19
20 A single cursor object may be used in many windows (any subwindow type).
21 The wxWidgets convention is to set the cursor for a window, as in X, rather
22 than to set it globally as in MS Windows, although a global wxSetCursor()
23 function is also available for MS Windows use.
24
25 @section cursor_custom Creating a Custom Cursor
26
27 The following is an example of creating a cursor from 32x32 bitmap data
28 (down_bits) and a mask (down_mask) where 1 is black and 0 is white for the
29 bits, and 1 is opaque and 0 is transparent for the mask.
30 It works on Windows and GTK+.
31
32 @code
33 static char down_bits[] = { 255, 255, 255, 255, 31,
34 255, 255, 255, 31, 255, 255, 255, 31, 255, 255, 255,
35 31, 255, 255, 255, 31, 255, 255, 255, 31, 255, 255,
36 255, 31, 255, 255, 255, 31, 255, 255, 255, 25, 243,
37 255, 255, 19, 249, 255, 255, 7, 252, 255, 255, 15, 254,
38 255, 255, 31, 255, 255, 255, 191, 255, 255, 255, 255,
39 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
40 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
41 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
42 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
43 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
44 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
45 255 };
46
47 static char down_mask[] = { 240, 1, 0, 0, 240, 1,
48 0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 240, 1,
49 0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 255, 31, 0, 0, 255,
50 31, 0, 0, 254, 15, 0, 0, 252, 7, 0, 0, 248, 3, 0, 0,
51 240, 1, 0, 0, 224, 0, 0, 0, 64, 0, 0, 0, 0, 0, 0, 0, 0,
52 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
53 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
54 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
55 0, 0, 0, 0, 0 };
56
57 #ifdef __WXMSW__
58 wxBitmap down_bitmap(down_bits, 32, 32);
59 wxBitmap down_mask_bitmap(down_mask, 32, 32);
60
61 down_bitmap.SetMask(new wxMask(down_mask_bitmap));
62 wxImage down_image = down_bitmap.ConvertToImage();
63 down_image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, 6);
64 down_image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y, 14);
65 wxCursor down_cursor = wxCursor(down_image);
66 #elif defined(__WXGTK__) or defined(__WXMOTIF__)
67 wxCursor down_cursor = wxCursor(down_bits, 32, 32, 6, 14,
68 down_mask, wxWHITE, wxBLACK);
69 #endif
70 @endcode
71
72 @library{wxcore}
73 @category{gdi}
74
75 @stdobjects
76 - ::wxNullCursor
77 - ::wxSTANDARD_CURSOR
78 - ::wxHOURGLASS_CURSOR
79 - ::wxCROSS_CURSOR
80
81 @see wxBitmap, wxIcon, wxWindow::SetCursor(), wxSetCursor(), ::wxStockCursor
82 */
83 class wxCursor : public wxGDIObject
84 {
85 public:
86 /**
87 Default constructor.
88 */
89 wxCursor();
90
91 /**
92 Constructs a cursor by passing an array of bits (XBM data).
93
94 The parameters @a fg and @a bg have an effect only on GTK+, and force
95 the cursor to use particular background and foreground colours.
96
97 If either @a hotSpotX or @a hotSpotY is -1, the hotspot will be the
98 centre of the cursor image (Motif only).
99
100 @param bits
101 An array of XBM data bits.
102 @param width
103 Cursor width.
104 @param height
105 Cursor height.
106 @param hotSpotX
107 Hotspot x coordinate (relative to the top left of the image).
108 @param hotSpotY
109 Hotspot y coordinate (relative to the top left of the image).
110 @param maskBits
111 Bits for a mask bitmap.
112
113 @onlyfor{wxgtk,wxmotif}
114
115 @beginWxPerlOnly
116 In wxPerl use Wx::Cursor->newData(bits, width, height, hotSpotX = -1, hotSpotY = -1, maskBits = 0).
117 @endWxPerlOnly
118 */
119 wxCursor(const char bits[], int width, int height,
120 int hotSpotX = -1, int hotSpotY = -1,
121 const char maskBits[] = NULL);
122
123 /**
124 Constructs a cursor by passing a string resource name or filename.
125
126 The arguments @a hotSpotX and @a hotSpotY are only used when there's no
127 hotspot info in the resource/image-file to load (e.g. when using
128 @c wxBITMAP_TYPE_ICO under wxMSW or @c wxBITMAP_TYPE_XPM under wxGTK).
129
130 @param cursorName
131 The name of the resource or the image file to load.
132 @param type
133 Icon type to load. It defaults to @c wxCURSOR_DEFAULT_TYPE,
134 which is a @#define associated to different values on different
135 platforms:
136 - under Windows, it defaults to @c wxBITMAP_TYPE_CUR_RESOURCE.
137 Other permitted types under Windows are @c wxBITMAP_TYPE_CUR
138 (to load a cursor from a .cur cursor file), @c wxBITMAP_TYPE_ICO
139 (to load a cursor from a .ico icon file) and @c wxBITMAP_TYPE_ANI
140 (to load a cursor from a .ani icon file).
141 - under MacOS, it defaults to @c wxBITMAP_TYPE_MACCURSOR_RESOURCE;
142 when specifying a string resource name, first the color cursors 'crsr'
143 and then the black/white cursors 'CURS' in the resource chain are scanned
144 through. Note that resource forks are deprecated on OS X so this
145 is only available for legacy reasons and should not be used in
146 new code.
147 - under GTK, it defaults to @c wxBITMAP_TYPE_XPM.
148 See the wxCursor(const wxImage& image) ctor for more info.
149 - under X11, it defaults to @c wxBITMAP_TYPE_XPM.
150 - under Motif, it defaults to @c wxBITMAP_TYPE_XBM.
151 @param hotSpotX
152 Hotspot x coordinate (relative to the top left of the image).
153 @param hotSpotY
154 Hotspot y coordinate (relative to the top left of the image).
155 */
156 wxCursor(const wxString& cursorName,
157 wxBitmapType type = wxCURSOR_DEFAULT_TYPE,
158 int hotSpotX = 0, int hotSpotY = 0);
159
160 /**
161 Constructs a cursor using a cursor identifier.
162
163 @param cursorId
164 A stock cursor identifier. See ::wxStockCursor.
165 */
166 wxCursor(wxStockCursor cursorId);
167
168 /**
169 Constructs a cursor from a wxImage. If cursor are monochrome on the
170 current platform, colors with the RGB elements all greater than 127
171 will be foreground, colors less than this background. The mask (if any)
172 will be used to specify the transparent area.
173
174 In wxMSW the foreground will be white and the background black.
175 If the cursor is larger than 32x32 it is resized.
176
177 In wxGTK, colour cursors and alpha channel are supported (starting from
178 GTK+ 2.2). Otherwise the two most frequent colors will be used for
179 foreground and background. In any case, the cursor will be displayed
180 at the size of the image.
181
182 Under wxMac (Cocoa), large cursors are supported.
183
184 Notice that the @a image can define the cursor hot spot. To set it you
185 need to use wxImage::SetOption() with @c wxIMAGE_OPTION_CUR_HOTSPOT_X
186 or @c wxIMAGE_OPTION_CUR_HOTSPOT_Y, e.g.
187 @code
188 image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, hotSpotX);
189 image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, hotSpotY);
190 @endcode
191 */
192 wxCursor(const wxImage& image);
193
194 /**
195 Copy constructor, uses @ref overview_refcount "reference counting".
196
197 @param cursor
198 Pointer or reference to a cursor to copy.
199 */
200 wxCursor(const wxCursor& cursor);
201
202 /**
203 Destroys the cursor. See
204 @ref overview_refcount_destruct "reference-counted object destruction"
205 for more info.
206
207 A cursor can be reused for more than one window, and does not get
208 destroyed when the window is destroyed. wxWidgets destroys all cursors
209 on application exit, although it is best to clean them up explicitly.
210 */
211 virtual ~wxCursor();
212
213 /**
214 Returns @true if cursor data is present.
215 */
216 virtual bool IsOk() const;
217
218 /**
219 Assignment operator, using @ref overview_refcount "reference counting".
220 */
221 wxCursor& operator =(const wxCursor& cursor);
222 };
223
224
225 /**
226 @name Predefined cursors.
227
228 @see wxStockCursor
229 */
230 //@{
231 wxCursor wxNullCursor;
232 wxCursor* wxSTANDARD_CURSOR;
233 wxCursor* wxHOURGLASS_CURSOR;
234 wxCursor* wxCROSS_CURSOR;
235 //@}
236