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. If cursor are monochrome on the current
  78 platform, colors with the RGB elements all greater than 127 will be foreground,
  79 colors less than this background. The mask (if any) will be used to specify the
  80 transparent area.
  81
  82 In wxMSW the foreground will be white and the background black. If the cursor
  83 is larger than 32x32 it is resized.
  84
  85 In wxGTK, colour cursors and alpha channel are supported (starting from GTK+
  86 2.2). Otherwise the two most frequent colors will be used for foreground and
  87 background. In any case, the cursor will be displayed at the size of the image.
  88
  89 In wxMac, if the cursor is larger than 16x16 it is resized and currently only
  90 shown as black/white (mask respected).
  91
  92 \func{}{wxCursor}{\param{const wxCursor\&}{ cursor}}
  93
  94 Copy constructor, uses \helpref{reference counting}{trefcount}.
  95
  96 \wxheading{Parameters}
  97
  98 \docparam{bits}{An array of bits.}
  99
 100 \docparam{maskBits}{Bits for a mask bitmap.}
 101
 102 \docparam{width}{Cursor width.}
 103
 104 \docparam{height}{Cursor height.}
 105
 106 \docparam{hotSpotX}{Hotspot x coordinate.}
 107
 108 \docparam{hotSpotY}{Hotspot y coordinate.}
 109
 110 \docparam{type}{Icon type to load. Under Motif, {\it type} defaults to {\bf wxBITMAP\_TYPE\_XBM}. Under Windows,
 111 it defaults to {\bf wxBITMAP\_TYPE\_CUR\_RESOURCE}. Under MacOS, it defaults to {\bf wxBITMAP\_TYPE\_MACCURSOR\_RESOURCE}.
 112
 113 Under X, the permitted cursor types are:
 114
 115 \twocolwidtha{6cm}
 116 \begin{twocollist}\itemsep=0pt
 117 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_XBM}}{Load an X bitmap file.}
 118 \end{twocollist}
 119
 120 Under Windows, the permitted types are:
 121
 122 \twocolwidtha{6cm}
 123 \begin{twocollist}\itemsep=0pt
 124 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_CUR}}{Load a cursor from a .cur cursor file (only if USE\_RESOURCE\_LOADING\_IN\_MSW
 125 is enabled in setup.h).}
 126 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_CUR\_RESOURCE}}{Load a Windows resource (as specified in the .rc file).}
 127 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_ICO}}{Load a cursor from a .ico icon file (only if USE\_RESOURCE\_LOADING\_IN\_MSW
 128 is enabled in setup.h). Specify {\it hotSpotX} and {\it hotSpotY}.}
 129 \end{twocollist}}
 130
 131 \docparam{cursorId}{A stock cursor identifier. May be one of:
 132
 133 \twocolwidtha{6cm}
 134 \begin{twocollist}\itemsep=0pt
 135 \twocolitem{{\bf wxCURSOR\_ARROW}}{A standard arrow cursor.}
 136 \twocolitem{{\bf wxCURSOR\_RIGHT\_ARROW}}{A standard arrow cursor
 137 pointing to the right.}
 138 \twocolitem{{\bf wxCURSOR\_BLANK}}{Transparent cursor.}
 139 \twocolitem{{\bf wxCURSOR\_BULLSEYE}}{Bullseye cursor.}
 140 \twocolitem{{\bf wxCURSOR\_CHAR}}{Rectangular character cursor.}
 141 \twocolitem{{\bf wxCURSOR\_CROSS}}{A cross cursor.}
 142 \twocolitem{{\bf wxCURSOR\_HAND}}{A hand cursor.}
 143 \twocolitem{{\bf wxCURSOR\_IBEAM}}{An I-beam cursor (vertical line).}
 144 \twocolitem{{\bf wxCURSOR\_LEFT\_BUTTON}}{Represents a mouse with the left button depressed.}
 145 \twocolitem{{\bf wxCURSOR\_MAGNIFIER}}{A magnifier icon.}
 146 \twocolitem{{\bf wxCURSOR\_MIDDLE\_BUTTON}}{Represents a mouse with the middle button depressed.}
 147 \twocolitem{{\bf wxCURSOR\_NO\_ENTRY}}{A no-entry sign cursor.}
 148 \twocolitem{{\bf wxCURSOR\_PAINT\_BRUSH}}{A paintbrush cursor.}
 149 \twocolitem{{\bf wxCURSOR\_PENCIL}}{A pencil cursor.}
 150 \twocolitem{{\bf wxCURSOR\_POINT\_LEFT}}{A cursor that points left.}
 151 \twocolitem{{\bf wxCURSOR\_POINT\_RIGHT}}{A cursor that points right.}
 152 \twocolitem{{\bf wxCURSOR\_QUESTION\_ARROW}}{An arrow and question mark.}
 153 \twocolitem{{\bf wxCURSOR\_RIGHT\_BUTTON}}{Represents a mouse with the right button depressed.}
 154 \twocolitem{{\bf wxCURSOR\_SIZENESW}}{A sizing cursor pointing NE-SW.}
 155 \twocolitem{{\bf wxCURSOR\_SIZENS}}{A sizing cursor pointing N-S.}
 156 \twocolitem{{\bf wxCURSOR\_SIZENWSE}}{A sizing cursor pointing NW-SE.}
 157 \twocolitem{{\bf wxCURSOR\_SIZEWE}}{A sizing cursor pointing W-E.}
 158 \twocolitem{{\bf wxCURSOR\_SIZING}}{A general sizing cursor.}
 159 \twocolitem{{\bf wxCURSOR\_SPRAYCAN}}{A spraycan cursor.}
 160 \twocolitem{{\bf wxCURSOR\_WAIT}}{A wait cursor.}
 161 \twocolitem{{\bf wxCURSOR\_WATCH}}{A watch cursor.}
 162 \twocolitem{{\bf wxCURSOR\_ARROWWAIT}}{A cursor with both an arrow and
 163 an hourglass, (windows.)}
 164 \end{twocollist}\twocolwidtha{5cm}
 165
 166 Note that not all cursors are available on all platforms.}
 167
 168 \docparam{cursor}{Pointer or reference to a cursor to copy.}
 169
 170 \pythonnote{Constructors supported by wxPython are:\par
 171 \indented{2cm}{\begin{twocollist}
 172 \twocolitem{{\bf wxCursor(name, flags, hotSpotX=0,
 173 hotSpotY=0)}}{Constructs a cursor from a filename}
 174 \twocolitem{{\bf wxStockCursor(id)}}{Constructs a stock cursor }
 175 \end{twocollist}}
 176 }
 177
 178 \perlnote{Constructors supported by wxPerl are:\par
 179 \begin{itemize}
 180 \item{Wx::Cursor->new( name, type, hotSpotX = 0, hotSpotY = 0 )}
 181 \item{Wx::Cursor->new( id )}
 182 \item{Wx::Cursor->new( image )}
 183 \item{Wx::Cursor->newData( bits, width, height, hotSpotX = -1, hotSpotY = -1, maskBits = 0 )}
 184 \end{itemize}
 185 }
 186
 187 \wxheading{Example}
 188
 189 The following is an example of creating a
 190 cursor from 32x32 bitmap data ({\tt down\_bits}) and a mask
 191 ({\tt down\_mask}) where 1 is black and 0 is white for
 192 the bits, and 1 is opaque and 0 is transparent for
 193 the mask. It works on Windows and GTK+.
 194
 195 \begin{verbatim}
 196 static char down_bits[] = { 255, 255, 255, 255, 31,
 197   255, 255, 255, 31, 255, 255, 255, 31, 255, 255, 255,
 198   31, 255, 255, 255, 31, 255, 255, 255, 31, 255, 255,
 199   255, 31, 255, 255, 255, 31, 255, 255, 255, 25, 243,
 200   255, 255, 19, 249, 255, 255, 7, 252, 255, 255, 15, 254,
 201   255, 255, 31, 255, 255, 255, 191, 255, 255, 255, 255,
 202   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 203   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 204   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 205   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 206   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 207   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 208   255 };
 209
 210 static char down_mask[] = { 240, 1, 0, 0, 240, 1,
 211   0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 240, 1,
 212   0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 255, 31, 0, 0, 255,
 213   31, 0, 0, 254, 15, 0, 0, 252, 7, 0, 0, 248, 3, 0, 0,
 214   240, 1, 0, 0, 224, 0, 0, 0, 64, 0, 0, 0, 0, 0, 0, 0, 0,
 215   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 216   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 217   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 218   0, 0, 0, 0, 0 };
 219
 220 #ifdef __WXMSW__
 221 wxBitmap down_bitmap(down_bits, 32, 32);
 222 wxBitmap down_mask_bitmap(down_mask, 32, 32);
 223
 224 down_bitmap.SetMask(new wxMask(down_mask_bitmap));
 225 wxImage down_image = down_bitmap.ConvertToImage();
 226 down_image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, 6);
 227 down_image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y, 14);
 228 wxCursor down_cursor = wxCursor(down_image);
 229 #else
 230 wxCursor down_cursor = wxCursor(down_bits, 32, 32,
 231   6, 14, down_mask, wxWHITE, wxBLACK);
 232 #endif
 233 \end{verbatim}
 234
 235 \membersection{wxCursor::\destruct{wxCursor}}\label{wxcursordtor}
 236
 237 \func{}{\destruct{wxCursor}}{\void}
 238
 239 Destroys the cursor.
 240 See \helpref{reference-counted object destruction}{refcountdestruct} for more info.
 241
 242 A cursor can be reused for more
 243 than one window, and does not get destroyed when the window is
 244 destroyed. wxWidgets destroys all cursors on application exit, although
 245 it is best to clean them up explicitly.
 246
 247 \membersection{wxCursor::IsOk}\label{wxcursorisok}
 248
 249 \constfunc{bool}{IsOk}{\void}
 250
 251 Returns true if cursor data is present.
 252
 253 \membersection{wxCursor::operator $=$}\label{wxcursorassignment}
 254
 255 \func{wxCursor\&}{operator $=$}{\param{const wxCursor\& }{cursor}}
 256
 257 Assignment operator, using \helpref{reference counting}{trefcount}.
 258