docs/latex/wx/cursor.tex

   1 \section{\class{wxCursor}}\label{wxcursor}
   2
   3 A cursor is a small bitmap usually used for denoting where the mouse
   4 pointer is, with a picture that might indicate the interpretation of a
   5 mouse click. As with icons, cursors in X and MS Windows are created
   6 in a different manner. Therefore, separate cursors will be created for the
   7 different environments.  Platform-specific methods for creating a {\bf
   8 wxCursor} object are catered for, and this is an occasion where
   9 conditional compilation will probably be required (see \helpref{wxIcon}{wxicon} for
  10 an example).
  11
  12 A single cursor object may be used in many windows (any subwindow type).
  13 The wxWidgets convention is to set the cursor for a window, as in X,
  14 rather than to set it globally as in MS Windows, although a
  15 global \helpref{::wxSetCursor}{wxsetcursor} is also available for MS Windows use.
  16
  17 \wxheading{Derived from}
  18
  19 \helpref{wxBitmap}{wxbitmap}\\
  20 \helpref{wxGDIObject}{wxgdiobject}\\
  21 \helpref{wxObject}{wxobject}
  22
  23 \wxheading{Include files}
  24
  25 <wx/cursor.h>
  26
  27 \wxheading{Predefined objects}
  28
  29 Objects:
  30
  31 {\bf wxNullCursor}
  32
  33 Pointers:
  34
  35 {\bf wxSTANDARD\_CURSOR\\
  36 wxHOURGLASS\_CURSOR\\
  37 wxCROSS\_CURSOR}
  38
  39 \wxheading{See also}
  40
  41 \helpref{wxBitmap}{wxbitmap}, \helpref{wxIcon}{wxicon}, \helpref{wxWindow::SetCursor}{wxwindowsetcursor},\rtfsp
  42 \helpref{::wxSetCursor}{wxsetcursor}
  43
  44 \latexignore{\rtfignore{\wxheading{Members}}}
  45
  46 \membersection{wxCursor::wxCursor}\label{wxcursorctor}
  47
  48 \func{}{wxCursor}{\void}
  49
  50 Default constructor.
  51
  52 \func{}{wxCursor}{\param{const char}{ bits[]}, \param{int }{width},
  53  \param{int }{ height}, \param{int }{hotSpotX=-1}, \param{int }{hotSpotY=-1}, \param{const char }{maskBits[]=NULL},
  54  \param{wxColour*}{ fg=NULL}, \param{wxColour*}{ bg=NULL}}
  55
  56 Constructs a cursor by passing an array of bits (Motif and GTK+ only). {\it maskBits} is used only under
  57 Motif and GTK+. The parameters {\it fg} and {\it bg} are only present on GTK+, and force the
  58 cursor to use particular background and foreground colours.
  59
  60 If either {\it hotSpotX} or {\it hotSpotY} is -1, the hotspot will be the centre of the cursor image (Motif only).
  61
  62 \func{}{wxCursor}{\param{const wxString\& }{cursorName}, \param{long }{type}, \param{int }{hotSpotX=0}, \param{int }{hotSpotY=0}}
  63
  64 Constructs a cursor by passing a string resource name or filename.
  65
  66 On MacOS when specifying a string resource name, first the color cursors 'crsr' and then the black/white cursors 'CURS' in the resource chain are scanned through.
  67
  68 {\it hotSpotX} and {\it hotSpotY} are currently only used under Windows when loading from an
  69 icon file, to specify the cursor hotspot relative to the top left of the image.
  70
  71 \func{}{wxCursor}{\param{int}{ cursorId}}
  72
  73 Constructs a cursor using a cursor identifier.
  74
  75 \func{}{wxCursor}{\param{const wxImage\&}{ image}}
  76
  77 Constructs a cursor from a wxImage. The cursor is monochrome, colors with the RGB elements all greater
  78 than 127 will be foreground, colors less than this background. The mask (if any) will be used as transparent.
  79
  80 In MSW the foreground will be white and the background black. If the cursor is larger than 32x32 it is resized.
  81 In GTK, the two most frequent colors will be used for foreground and background. The cursor will be displayed
  82 at the size of the image.
  83 On MacOS if the cursor is larger than 16x16 it is resized and currently only shown as black/white (mask respected).
  84
  85 \func{}{wxCursor}{\param{const wxCursor\&}{ cursor}}
  86
  87 Copy constructor. This uses reference counting so is a cheap operation.
  88
  89 \wxheading{Parameters}
  90
  91 \docparam{bits}{An array of bits.}
  92
  93 \docparam{maskBits}{Bits for a mask bitmap.}
  94
  95 \docparam{width}{Cursor width.}
  96
  97 \docparam{height}{Cursor height.}
  98
  99 \docparam{hotSpotX}{Hotspot x coordinate.}
 100
 101 \docparam{hotSpotY}{Hotspot y coordinate.}
 102
 103 \docparam{type}{Icon type to load. Under Motif, {\it type} defaults to {\bf wxBITMAP\_TYPE\_XBM}. Under Windows,
 104 it defaults to {\bf wxBITMAP\_TYPE\_CUR\_RESOURCE}. Under MacOS, it defaults to {\bf wxBITMAP\_TYPE\_MACCURSOR\_RESOURCE}.
 105
 106 Under X, the permitted cursor types are:
 107
 108 \twocolwidtha{6cm}
 109 \begin{twocollist}\itemsep=0pt
 110 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_XBM}}{Load an X bitmap file.}
 111 \end{twocollist}
 112
 113 Under Windows, the permitted types are:
 114
 115 \twocolwidtha{6cm}
 116 \begin{twocollist}\itemsep=0pt
 117 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_CUR}}{Load a cursor from a .cur cursor file (only if USE\_RESOURCE\_LOADING\_IN\_MSW
 118 is enabled in setup.h).}
 119 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_CUR\_RESOURCE}}{Load a Windows resource (as specified in the .rc file).}
 120 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_ICO}}{Load a cursor from a .ico icon file (only if USE\_RESOURCE\_LOADING\_IN\_MSW
 121 is enabled in setup.h). Specify {\it hotSpotX} and {\it hotSpotY}.}
 122 \end{twocollist}}
 123
 124 \docparam{cursorId}{A stock cursor identifier. May be one of:
 125
 126 \twocolwidtha{6cm}
 127 \begin{twocollist}\itemsep=0pt
 128 \twocolitem{{\bf wxCURSOR\_ARROW}}{A standard arrow cursor.}
 129 \twocolitem{{\bf wxCURSOR\_RIGHT\_ARROW}}{A standard arrow cursor
 130 pointing to the right.}
 131 \twocolitem{{\bf wxCURSOR\_BLANK}}{Transparent cursor.}
 132 \twocolitem{{\bf wxCURSOR\_BULLSEYE}}{Bullseye cursor.}
 133 \twocolitem{{\bf wxCURSOR\_CHAR}}{Rectangular character cursor.}
 134 \twocolitem{{\bf wxCURSOR\_CROSS}}{A cross cursor.}
 135 \twocolitem{{\bf wxCURSOR\_HAND}}{A hand cursor.}
 136 \twocolitem{{\bf wxCURSOR\_IBEAM}}{An I-beam cursor (vertical line).}
 137 \twocolitem{{\bf wxCURSOR\_LEFT\_BUTTON}}{Represents a mouse with the left button depressed.}
 138 \twocolitem{{\bf wxCURSOR\_MAGNIFIER}}{A magnifier icon.}
 139 \twocolitem{{\bf wxCURSOR\_MIDDLE\_BUTTON}}{Represents a mouse with the middle button depressed.}
 140 \twocolitem{{\bf wxCURSOR\_NO\_ENTRY}}{A no-entry sign cursor.}
 141 \twocolitem{{\bf wxCURSOR\_PAINT\_BRUSH}}{A paintbrush cursor.}
 142 \twocolitem{{\bf wxCURSOR\_PENCIL}}{A pencil cursor.}
 143 \twocolitem{{\bf wxCURSOR\_POINT\_LEFT}}{A cursor that points left.}
 144 \twocolitem{{\bf wxCURSOR\_POINT\_RIGHT}}{A cursor that points right.}
 145 \twocolitem{{\bf wxCURSOR\_QUESTION\_ARROW}}{An arrow and question mark.}
 146 \twocolitem{{\bf wxCURSOR\_RIGHT\_BUTTON}}{Represents a mouse with the right button depressed.}
 147 \twocolitem{{\bf wxCURSOR\_SIZENESW}}{A sizing cursor pointing NE-SW.}
 148 \twocolitem{{\bf wxCURSOR\_SIZENS}}{A sizing cursor pointing N-S.}
 149 \twocolitem{{\bf wxCURSOR\_SIZENWSE}}{A sizing cursor pointing NW-SE.}
 150 \twocolitem{{\bf wxCURSOR\_SIZEWE}}{A sizing cursor pointing W-E.}
 151 \twocolitem{{\bf wxCURSOR\_SIZING}}{A general sizing cursor.}
 152 \twocolitem{{\bf wxCURSOR\_SPRAYCAN}}{A spraycan cursor.}
 153 \twocolitem{{\bf wxCURSOR\_WAIT}}{A wait cursor.}
 154 \twocolitem{{\bf wxCURSOR\_WATCH}}{A watch cursor.}
 155 \twocolitem{{\bf wxCURSOR\_ARROWWAIT}}{A cursor with both an arrow and
 156 an hourglass, (windows.)}
 157 \end{twocollist}\twocolwidtha{5cm}
 158
 159 Note that not all cursors are available on all platforms.}
 160
 161 \docparam{cursor}{Pointer or reference to a cursor to copy.}
 162
 163 \pythonnote{Constructors supported by wxPython are:\par
 164 \indented{2cm}{\begin{twocollist}
 165 \twocolitem{{\bf wxCursor(name, flags, hotSpotX=0,
 166 hotSpotY=0)}}{Constructs a cursor from a filename}
 167 \twocolitem{{\bf wxStockCursor(id)}}{Constructs a stock cursor }
 168 \end{twocollist}}
 169 }
 170
 171 \perlnote{Constructors supported by wxPerl are:\par
 172 \begin{itemize}
 173 \item{Wx::Cursor->new( name, type, hotSpotX = 0, hotSpotY = 0 )}
 174 \item{Wx::Cursor->new( id )}
 175 \item{Wx::Cursor->new( image )}
 176 \item{Wx::Cursor->newData( bits, width, height, hotSpotX = -1, hotSpotY = -1, maskBits = 0 )}
 177 \end{itemize}
 178 }
 179
 180 \wxheading{Example}
 181
 182 The following is an example of creating a
 183 cursor from 32x32 bitmap data ({\tt down\_bits}) and a mask
 184 ({\tt down\_mask}) where 1 is black and 0 is white for
 185 the bits, and 1 is opaque and 0 is transparent for
 186 the mask. It works on Windows and GTK+.
 187
 188 \begin{verbatim}
 189 static char down_bits[] = { 255, 255, 255, 255, 31,
 190   255, 255, 255, 31, 255, 255, 255, 31, 255, 255, 255,
 191   31, 255, 255, 255, 31, 255, 255, 255, 31, 255, 255,
 192   255, 31, 255, 255, 255, 31, 255, 255, 255, 25, 243,
 193   255, 255, 19, 249, 255, 255, 7, 252, 255, 255, 15, 254,
 194   255, 255, 31, 255, 255, 255, 191, 255, 255, 255, 255,
 195   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 196   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 197   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 198   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 199   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 200   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 201   255 };
 202
 203 static char down_mask[] = { 240, 1, 0, 0, 240, 1,
 204   0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 240, 1,
 205   0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 255, 31, 0, 0, 255,
 206   31, 0, 0, 254, 15, 0, 0, 252, 7, 0, 0, 248, 3, 0, 0,
 207   240, 1, 0, 0, 224, 0, 0, 0, 64, 0, 0, 0, 0, 0, 0, 0, 0,
 208   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 209   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 210   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 211   0, 0, 0, 0, 0 };
 212
 213 #ifdef __WXMSW__
 214 wxBitmap down_bitmap(down_bits, 32, 32);
 215 wxBitmap down_mask_bitmap(down_mask, 32, 32);
 216
 217 down_bitmap.SetMask(new wxMask(down_mask_bitmap));
 218 wxImage down_image = down_bitmap.ConvertToImage();
 219 down_image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, 6);
 220 down_image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y, 14);
 221 wxCursor down_cursor = wxCursor(down_image);
 222 #else
 223 wxCursor down_cursor = wxCursor(down_bits, 32, 32,
 224   6, 14, down_mask, wxWHITE, wxBLACK);
 225 #endif
 226 \end{verbatim}
 227
 228 \membersection{wxCursor::\destruct{wxCursor}}\label{wxcursordtor}
 229
 230 \func{}{\destruct{wxCursor}}{\void}
 231
 232 Destroys the cursor. A cursor can be reused for more
 233 than one window, and does not get destroyed when the window is
 234 destroyed. wxWidgets destroys all cursors on application exit, although
 235 it is best to clean them up explicitly.
 236
 237 \membersection{wxCursor::Ok}\label{wxcursorok}
 238
 239 \constfunc{bool}{Ok}{\void}
 240
 241 Returns true if cursor data is present.
 242
 243 \membersection{wxCursor::operator $=$}\label{wxcursorassignment}
 244
 245 \func{wxCursor\&}{operator $=$}{\param{const wxCursor\& }{cursor}}
 246
 247 Assignment operator, using reference counting. Returns a reference
 248 to `this'.
 249
 250 \membersection{wxCursor::operator $==$}\label{wxcursorequals}
 251
 252 \func{bool}{operator $==$}{\param{const wxCursor\& }{cursor}}
 253
 254 Equality operator. Two cursors are equal if they contain pointers
 255 to the same underlying cursor data. It does not compare each attribute,
 256 so two independently-created cursors using the same parameters will
 257 fail the test.
 258
 259 \membersection{wxCursor::operator $!=$}\label{wxcursornotequals}
 260
 261 \func{bool}{operator $!=$}{\param{const wxCursor\& }{cursor}}
 262
 263 Inequality operator. Two cursors are not equal if they contain pointers
 264 to different underlying cursor data. It does not compare each attribute.
 265
 266