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{Library}
  28
  29 \helpref{wxCore}{librarieslist}
  30
  31 \wxheading{Predefined objects}
  32
  33 Objects:
  34
  35 {\bf wxNullCursor}
  36
  37 Pointers:
  38
  39 {\bf wxSTANDARD\_CURSOR\\
  40 wxHOURGLASS\_CURSOR\\
  41 wxCROSS\_CURSOR}
  42
  43 \wxheading{See also}
  44
  45 \helpref{wxBitmap}{wxbitmap}, \helpref{wxIcon}{wxicon}, \helpref{wxWindow::SetCursor}{wxwindowsetcursor},\rtfsp
  46 \helpref{::wxSetCursor}{wxsetcursor}
  47
  48 \latexignore{\rtfignore{\wxheading{Members}}}
  49
  50 \membersection{wxCursor::wxCursor}\label{wxcursorctor}
  51
  52 \func{}{wxCursor}{\void}
  53
  54 Default constructor.
  55
  56 \func{}{wxCursor}{\param{const char}{ bits[]}, \param{int }{width},
  57  \param{int }{ height}, \param{int }{hotSpotX=-1}, \param{int }{hotSpotY=-1}, \param{const char }{maskBits[]=NULL},
  58  \param{wxColour*}{ fg=NULL}, \param{wxColour*}{ bg=NULL}}
  59
  60 Constructs a cursor by passing an array of bits (Motif and GTK+ only). {\it maskBits} is used only under
  61 Motif and GTK+. The parameters {\it fg} and {\it bg} are only present on GTK+, and force the
  62 cursor to use particular background and foreground colours.
  63
  64 If either {\it hotSpotX} or {\it hotSpotY} is -1, the hotspot will be the centre of the cursor image (Motif only).
  65
  66 \func{}{wxCursor}{\param{const wxString\& }{cursorName}, \param{long }{type}, \param{int }{hotSpotX=0}, \param{int }{hotSpotY=0}}
  67
  68 Constructs a cursor by passing a string resource name or filename.
  69
  70 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.
  71
  72 {\it hotSpotX} and {\it hotSpotY} are currently only used under Windows when loading from an
  73 icon file, to specify the cursor hotspot relative to the top left of the image.
  74
  75 \func{}{wxCursor}{\param{int}{ cursorId}}
  76
  77 Constructs a cursor using a cursor identifier.
  78
  79 \func{}{wxCursor}{\param{const wxImage\&}{ image}}
  80
  81 Constructs a cursor from a wxImage. If cursor are monochrome on the current
  82 platform, colors with the RGB elements all greater than 127 will be foreground,
  83 colors less than this background. The mask (if any) will be used to specify the
  84 transparent area.
  85
  86 In wxMSW the foreground will be white and the background black. If the cursor
  87 is larger than 32x32 it is resized.
  88
  89 In wxGTK, colour cursors and alpha channel are supported (starting from GTK+
  90 2.2). Otherwise the two most frequent colors will be used for foreground and
  91 background. In any case, the cursor will be displayed at the size of the image.
  92
  93 In wxMac, if the cursor is larger than 16x16 it is resized and currently only
  94 shown as black/white (mask respected).
  95
  96 \func{}{wxCursor}{\param{const wxCursor\&}{ cursor}}
  97
  98 Copy constructor, uses \helpref{reference counting}{trefcount}.
  99
 100 \wxheading{Parameters}
 101
 102 \docparam{bits}{An array of bits.}
 103
 104 \docparam{maskBits}{Bits for a mask bitmap.}
 105
 106 \docparam{width}{Cursor width.}
 107
 108 \docparam{height}{Cursor height.}
 109
 110 \docparam{hotSpotX}{Hotspot x coordinate.}
 111
 112 \docparam{hotSpotY}{Hotspot y coordinate.}
 113
 114 \docparam{type}{Icon type to load. Under Motif, {\it type} defaults to {\bf wxBITMAP\_TYPE\_XBM}. Under Windows,
 115 it defaults to {\bf wxBITMAP\_TYPE\_CUR\_RESOURCE}. Under MacOS, it defaults to {\bf wxBITMAP\_TYPE\_MACCURSOR\_RESOURCE}.
 116
 117 Under X, the permitted cursor types are:
 118
 119 \twocolwidtha{6cm}
 120 \begin{twocollist}\itemsep=0pt
 121 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_XBM}}{Load an X bitmap file.}
 122 \end{twocollist}
 123
 124 Under Windows, the permitted types are:
 125
 126 \twocolwidtha{6cm}
 127 \begin{twocollist}\itemsep=0pt
 128 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_CUR}}{Load a cursor from a .cur cursor file (only if USE\_RESOURCE\_LOADING\_IN\_MSW
 129 is enabled in setup.h).}
 130 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_CUR\_RESOURCE}}{Load a Windows resource (as specified in the .rc file).}
 131 \twocolitem{\windowstyle{wxBITMAP\_TYPE\_ICO}}{Load a cursor from a .ico icon file (only if USE\_RESOURCE\_LOADING\_IN\_MSW
 132 is enabled in setup.h). Specify {\it hotSpotX} and {\it hotSpotY}.}
 133 \end{twocollist}}
 134
 135 \docparam{cursorId}{A stock cursor identifier. May be one of:
 136
 137 \twocolwidtha{6cm}
 138 \begin{twocollist}\itemsep=0pt
 139 \twocolitem{{\bf wxCURSOR\_ARROW}}{A standard arrow cursor.}
 140 \twocolitem{{\bf wxCURSOR\_RIGHT\_ARROW}}{A standard arrow cursor
 141 pointing to the right.}
 142 \twocolitem{{\bf wxCURSOR\_BLANK}}{Transparent cursor.}
 143 \twocolitem{{\bf wxCURSOR\_BULLSEYE}}{Bullseye cursor.}
 144 \twocolitem{{\bf wxCURSOR\_CHAR}}{Rectangular character cursor.}
 145 \twocolitem{{\bf wxCURSOR\_CROSS}}{A cross cursor.}
 146 \twocolitem{{\bf wxCURSOR\_HAND}}{A hand cursor.}
 147 \twocolitem{{\bf wxCURSOR\_IBEAM}}{An I-beam cursor (vertical line).}
 148 \twocolitem{{\bf wxCURSOR\_LEFT\_BUTTON}}{Represents a mouse with the left button depressed.}
 149 \twocolitem{{\bf wxCURSOR\_MAGNIFIER}}{A magnifier icon.}
 150 \twocolitem{{\bf wxCURSOR\_MIDDLE\_BUTTON}}{Represents a mouse with the middle button depressed.}
 151 \twocolitem{{\bf wxCURSOR\_NO\_ENTRY}}{A no-entry sign cursor.}
 152 \twocolitem{{\bf wxCURSOR\_PAINT\_BRUSH}}{A paintbrush cursor.}
 153 \twocolitem{{\bf wxCURSOR\_PENCIL}}{A pencil cursor.}
 154 \twocolitem{{\bf wxCURSOR\_POINT\_LEFT}}{A cursor that points left.}
 155 \twocolitem{{\bf wxCURSOR\_POINT\_RIGHT}}{A cursor that points right.}
 156 \twocolitem{{\bf wxCURSOR\_QUESTION\_ARROW}}{An arrow and question mark.}
 157 \twocolitem{{\bf wxCURSOR\_RIGHT\_BUTTON}}{Represents a mouse with the right button depressed.}
 158 \twocolitem{{\bf wxCURSOR\_SIZENESW}}{A sizing cursor pointing NE-SW.}
 159 \twocolitem{{\bf wxCURSOR\_SIZENS}}{A sizing cursor pointing N-S.}
 160 \twocolitem{{\bf wxCURSOR\_SIZENWSE}}{A sizing cursor pointing NW-SE.}
 161 \twocolitem{{\bf wxCURSOR\_SIZEWE}}{A sizing cursor pointing W-E.}
 162 \twocolitem{{\bf wxCURSOR\_SIZING}}{A general sizing cursor.}
 163 \twocolitem{{\bf wxCURSOR\_SPRAYCAN}}{A spraycan cursor.}
 164 \twocolitem{{\bf wxCURSOR\_WAIT}}{A wait cursor.}
 165 \twocolitem{{\bf wxCURSOR\_WATCH}}{A watch cursor.}
 166 \twocolitem{{\bf wxCURSOR\_ARROWWAIT}}{A cursor with both an arrow and
 167 an hourglass, (windows.)}
 168 \end{twocollist}\twocolwidtha{5cm}
 169
 170 Note that not all cursors are available on all platforms.}
 171
 172 \docparam{cursor}{Pointer or reference to a cursor to copy.}
 173
 174 \pythonnote{Constructors supported by wxPython are:\par
 175 \indented{2cm}{\begin{twocollist}
 176 \twocolitem{{\bf wxCursor(name, flags, hotSpotX=0,
 177 hotSpotY=0)}}{Constructs a cursor from a filename}
 178 \twocolitem{{\bf wxStockCursor(id)}}{Constructs a stock cursor }
 179 \end{twocollist}}
 180 }
 181
 182 \perlnote{Constructors supported by wxPerl are:\par
 183 \begin{itemize}
 184 \item{Wx::Cursor->new( name, type, hotSpotX = 0, hotSpotY = 0 )}
 185 \item{Wx::Cursor->new( id )}
 186 \item{Wx::Cursor->new( image )}
 187 \item{Wx::Cursor->newData( bits, width, height, hotSpotX = -1, hotSpotY = -1, maskBits = 0 )}
 188 \end{itemize}
 189 }
 190
 191 \wxheading{Example}
 192
 193 The following is an example of creating a
 194 cursor from 32x32 bitmap data ({\tt down\_bits}) and a mask
 195 ({\tt down\_mask}) where 1 is black and 0 is white for
 196 the bits, and 1 is opaque and 0 is transparent for
 197 the mask. It works on Windows and GTK+.
 198
 199 \begin{verbatim}
 200 static char down_bits[] = { 255, 255, 255, 255, 31,
 201   255, 255, 255, 31, 255, 255, 255, 31, 255, 255, 255,
 202   31, 255, 255, 255, 31, 255, 255, 255, 31, 255, 255,
 203   255, 31, 255, 255, 255, 31, 255, 255, 255, 25, 243,
 204   255, 255, 19, 249, 255, 255, 7, 252, 255, 255, 15, 254,
 205   255, 255, 31, 255, 255, 255, 191, 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, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 209   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 210   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 211   255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
 212   255 };
 213
 214 static char down_mask[] = { 240, 1, 0, 0, 240, 1,
 215   0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 240, 1,
 216   0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 255, 31, 0, 0, 255,
 217   31, 0, 0, 254, 15, 0, 0, 252, 7, 0, 0, 248, 3, 0, 0,
 218   240, 1, 0, 0, 224, 0, 0, 0, 64, 0, 0, 0, 0, 0, 0, 0, 0,
 219   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 220   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 221   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 222   0, 0, 0, 0, 0 };
 223
 224 #ifdef __WXMSW__
 225 wxBitmap down_bitmap(down_bits, 32, 32);
 226 wxBitmap down_mask_bitmap(down_mask, 32, 32);
 227
 228 down_bitmap.SetMask(new wxMask(down_mask_bitmap));
 229 wxImage down_image = down_bitmap.ConvertToImage();
 230 down_image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, 6);
 231 down_image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y, 14);
 232 wxCursor down_cursor = wxCursor(down_image);
 233 #else
 234 wxCursor down_cursor = wxCursor(down_bits, 32, 32,
 235   6, 14, down_mask, wxWHITE, wxBLACK);
 236 #endif
 237 \end{verbatim}
 238
 239 \membersection{wxCursor::\destruct{wxCursor}}\label{wxcursordtor}
 240
 241 \func{}{\destruct{wxCursor}}{\void}
 242
 243 Destroys the cursor.
 244 See \helpref{reference-counted object destruction}{refcountdestruct} for more info.
 245
 246 A cursor can be reused for more
 247 than one window, and does not get destroyed when the window is
 248 destroyed. wxWidgets destroys all cursors on application exit, although
 249 it is best to clean them up explicitly.
 250
 251 \membersection{wxCursor::IsOk}\label{wxcursorisok}
 252
 253 \constfunc{bool}{IsOk}{\void}
 254
 255 Returns true if cursor data is present.
 256
 257 \membersection{wxCursor::operator $=$}\label{wxcursorassignment}
 258
 259 \func{wxCursor\&}{operator $=$}{\param{const wxCursor\& }{cursor}}
 260
 261 Assignment operator, using \helpref{reference counting}{trefcount}.
 262