Version: 3.1.0
wxCursor Class Reference

#include <wx/cursor.h>

+ Inheritance diagram for wxCursor:

Detailed Description

A cursor is a small bitmap usually used for denoting where the mouse pointer is, with a picture that might indicate the interpretation of a mouse click.

As with icons, cursors in X and MS Windows are created in a different manner. Therefore, separate cursors will be created for the different environments. Platform-specific methods for creating a wxCursor object are catered for, and this is an occasion where conditional compilation will probably be required (see wxIcon for an example).

A single cursor object may be used in many windows (any subwindow type). The wxWidgets convention is to set the cursor for a window, as in X, rather than to set it globally as in MS Windows, although a global wxSetCursor() function is also available for MS Windows use.

Creating a Custom Cursor

The following is an example of creating a cursor from 32x32 bitmap data (down_bits) and a mask (down_mask) where 1 is black and 0 is white for the bits, and 1 is opaque and 0 is transparent for the mask. It works on Windows and GTK+.

static char down_bits[] = { 255, 255, 255, 255, 31,
255, 255, 255, 31, 255, 255, 255, 31, 255, 255, 255,
31, 255, 255, 255, 31, 255, 255, 255, 31, 255, 255,
255, 31, 255, 255, 255, 31, 255, 255, 255, 25, 243,
255, 255, 19, 249, 255, 255, 7, 252, 255, 255, 15, 254,
255, 255, 31, 255, 255, 255, 191, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255 };
static char down_mask[] = { 240, 1, 0, 0, 240, 1,
0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 240, 1,
0, 0, 240, 1, 0, 0, 240, 1, 0, 0, 255, 31, 0, 0, 255,
31, 0, 0, 254, 15, 0, 0, 252, 7, 0, 0, 248, 3, 0, 0,
240, 1, 0, 0, 224, 0, 0, 0, 64, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0 };
#ifdef __WXMSW__
wxBitmap down_bitmap(down_bits, 32, 32);
wxBitmap down_mask_bitmap(down_mask, 32, 32);
down_bitmap.SetMask(new wxMask(down_mask_bitmap));
wxImage down_image = down_bitmap.ConvertToImage();
wxCursor down_cursor = wxCursor(down_image);
#elif defined(__WXGTK__) or defined(__WXMOTIF__)
wxCursor down_cursor = wxCursor(down_bits, 32, 32, 6, 14,
down_mask, wxWHITE, wxBLACK);
#endif

Library:  wxCore
Category:  Graphics Device Interface (GDI)

Predefined objects/pointers:

See Also
wxBitmap, wxIcon, wxWindow::SetCursor(), wxSetCursor(), wxStockCursor

Public Member Functions

 wxCursor ()
 Default constructor.
 
 wxCursor (const char bits[], int width, int height, int hotSpotX=-1, int hotSpotY=-1, const char maskBits[]=NULL)
 Constructs a cursor by passing an array of bits (XBM data).
 
 wxCursor (const wxString &cursorName, wxBitmapType type=wxCURSOR_DEFAULT_TYPE, int hotSpotX=0, int hotSpotY=0)
 Constructs a cursor by passing a string resource name or filename.
 
 wxCursor (wxStockCursor cursorId)
 Constructs a cursor using a cursor identifier.
 
 wxCursor (const wxImage &image)
 Constructs a cursor from a wxImage.
 
 wxCursor (const wxCursor &cursor)
 Copy constructor, uses reference counting.
 
virtual ~wxCursor ()
 Destroys the cursor.
 
virtual bool IsOk () const
 Returns true if cursor data is present.
 
wxCursoroperator= (const wxCursor &cursor)
 Assignment operator, using reference counting.
 
- Public Member Functions inherited from wxGDIObject
 wxGDIObject ()
 Default constructor.
 
- Public Member Functions inherited from wxObject
 wxObject ()
 Default ctor; initializes to NULL the internal reference data.
 
 wxObject (const wxObject &other)
 Copy ctor.
 
virtual ~wxObject ()
 Destructor.
 
virtual wxClassInfoGetClassInfo () const
 This virtual function is redefined for every class that requires run-time type information, when using the wxDECLARE_CLASS macro (or similar).
 
wxObjectRefDataGetRefData () const
 Returns the wxObject::m_refData pointer, i.e. the data referenced by this object.
 
bool IsKindOf (const wxClassInfo *info) const
 Determines whether this class is a subclass of (or the same class as) the given class.
 
bool IsSameAs (const wxObject &obj) const
 Returns true if this object has the same data pointer as obj.
 
void Ref (const wxObject &clone)
 Makes this object refer to the data in clone.
 
void SetRefData (wxObjectRefData *data)
 Sets the wxObject::m_refData pointer.
 
void UnRef ()
 Decrements the reference count in the associated data, and if it is zero, deletes the data.
 
void UnShare ()
 This is the same of AllocExclusive() but this method is public.
 
void operator delete (void *buf)
 The delete operator is defined for debugging versions of the library only, when the identifier WXDEBUG is defined.
 
void * operator new (size_t size, const wxString &filename=NULL, int lineNum=0)
 The new operator is defined for debugging versions of the library only, when the identifier WXDEBUG is defined.
 

Additional Inherited Members

- Protected Member Functions inherited from wxObject
void AllocExclusive ()
 Ensure that this object's data is not shared with any other object.
 
virtual wxObjectRefDataCreateRefData () const
 Creates a new instance of the wxObjectRefData-derived class specific to this object and returns it.
 
virtual wxObjectRefDataCloneRefData (const wxObjectRefData *data) const
 Creates a new instance of the wxObjectRefData-derived class specific to this object and initializes it copying data.
 
- Protected Attributes inherited from wxObject
wxObjectRefDatam_refData
 Pointer to an object which is the object's reference-counted data.
 

Constructor & Destructor Documentation

wxCursor::wxCursor ( )

Default constructor.

wxCursor::wxCursor ( const char  bits[],
int  width,
int  height,
int  hotSpotX = -1,
int  hotSpotY = -1,
const char  maskBits[] = NULL 
)

Constructs a cursor by passing an array of bits (XBM data).

The parameters fg and bg have an effect only on GTK+, and force the cursor to use particular background and foreground colours.

If either hotSpotX or hotSpotY is -1, the hotspot will be the centre of the cursor image (Motif only).

Parameters
bitsAn array of XBM data bits.
widthCursor width.
heightCursor height.
hotSpotXHotspot x coordinate (relative to the top left of the image).
hotSpotYHotspot y coordinate (relative to the top left of the image).
maskBitsBits for a mask bitmap.
Availability:  only available for the wxGTK, wxMotif ports.

wxPerl Note: In wxPerl use Wx::Cursor->newData(bits, width, height, hotSpotX = -1, hotSpotY = -1, maskBits = 0).

wxCursor::wxCursor ( const wxString cursorName,
wxBitmapType  type = wxCURSOR_DEFAULT_TYPE,
int  hotSpotX = 0,
int  hotSpotY = 0 
)

Constructs a cursor by passing a string resource name or filename.

The arguments hotSpotX and hotSpotY are only used when there's no hotspot info in the resource/image-file to load (e.g. when using wxBITMAP_TYPE_ICO under wxMSW or wxBITMAP_TYPE_XPM under wxGTK).

Parameters
cursorNameThe name of the resource or the image file to load.
typeIcon type to load. It defaults to wxCURSOR_DEFAULT_TYPE, which is a #define associated to different values on different platforms:
  • under Windows, it defaults to wxBITMAP_TYPE_CUR_RESOURCE. Other permitted types under Windows are wxBITMAP_TYPE_CUR (to load a cursor from a .cur cursor file), wxBITMAP_TYPE_ICO (to load a cursor from a .ico icon file) and wxBITMAP_TYPE_ANI (to load a cursor from a .ani icon file).
  • under MacOS, it defaults to wxBITMAP_TYPE_MACCURSOR_RESOURCE; 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. Note that resource forks are deprecated on OS X so this is only available for legacy reasons and should not be used in new code.
  • under GTK, it defaults to wxBITMAP_TYPE_XPM. See the wxCursor(const wxImage& image) ctor for more info.
  • under X11, it defaults to wxBITMAP_TYPE_XPM.
  • under Motif, it defaults to wxBITMAP_TYPE_XBM.
hotSpotXHotspot x coordinate (relative to the top left of the image).
hotSpotYHotspot y coordinate (relative to the top left of the image).
wxCursor::wxCursor ( wxStockCursor  cursorId)

Constructs a cursor using a cursor identifier.

Parameters
cursorIdA stock cursor identifier. See wxStockCursor.
wxCursor::wxCursor ( const wxImage image)

Constructs a cursor from a wxImage.

If cursor are monochrome on the current platform, colors with the RGB elements all greater than 127 will be foreground, colors less than this background. The mask (if any) will be used to specify the transparent area.

In wxMSW the foreground will be white and the background black. If the cursor is larger than 32x32 it is resized.

In wxGTK, colour cursors and alpha channel are supported (starting from GTK+ 2.2). Otherwise the two most frequent colors will be used for foreground and background. In any case, the cursor will be displayed at the size of the image.

Under wxMac (Cocoa), large cursors are supported.

Notice that the image can define the cursor hot spot. To set it you need to use wxImage::SetOption() with wxIMAGE_OPTION_CUR_HOTSPOT_X or wxIMAGE_OPTION_CUR_HOTSPOT_Y, e.g.

image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, hotSpotX);
image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, hotSpotY);
wxCursor::wxCursor ( const wxCursor cursor)

Copy constructor, uses reference counting.

Parameters
cursorPointer or reference to a cursor to copy.
virtual wxCursor::~wxCursor ( )
virtual

Destroys the cursor.

See reference-counted object destruction for more info.

A cursor can be reused for more than one window, and does not get destroyed when the window is destroyed. wxWidgets destroys all cursors on application exit, although it is best to clean them up explicitly.

Member Function Documentation

virtual bool wxCursor::IsOk ( ) const
virtual

Returns true if cursor data is present.

wxCursor& wxCursor::operator= ( const wxCursor cursor)

Assignment operator, using reference counting.