QCursor Class

The QCursor class provides a mouse cursor with an arbitrary shape. More...

Header: #include <QCursor>
qmake: QT += gui

Public Functions

QCursor(const QCursor &c)
QCursor(const QPixmap &pixmap, int hotX = -1, int hotY = -1)
QCursor(const QBitmap &bitmap, const QBitmap &mask, int hotX = -1, int hotY = -1)
QCursor(Qt::CursorShape shape)
QCursor()
QCursor &operator=(const QCursor &c)
~QCursor()
const QBitmap *bitmap() const
QPoint hotSpot() const
const QBitmap *mask() const
QPixmap pixmap() const
void setShape(Qt::CursorShape shape)
Qt::CursorShape shape() const
QVariant operator QVariant() const

Detailed Description

This class is mainly used to create mouse cursors that are associated with particular widgets and to get and set the position of the mouse cursor.

Qt has a number of standard cursor shapes, but you can also make custom cursor shapes based on a QBitmap, a mask and a hotspot.

To associate a cursor with a widget, use QWidget::setCursor(). To associate a cursor with all widgets (normally for a short period of time), use QGuiApplication::setOverrideCursor().

To set a cursor shape use QCursor::setShape() or use the QCursor constructor which takes the shape as argument, or you can use one of the predefined cursors defined in the Qt::CursorShape enum.

If you want to create a cursor with your own bitmap, either use the QCursor constructor which takes a bitmap and a mask or the constructor which takes a pixmap as arguments.

To set or get the position of the mouse cursor use the static methods QCursor::pos() and QCursor::setPos().

Note: It is possible to create a QCursor before QGuiApplication, but it is not useful except as a place-holder for a real QCursor created after QGuiApplication. Attempting to use a QCursor that was created before QGuiApplication will result in a crash.

A Note for X11 Users

On X11, Qt supports the Xcursor library, which allows for full color icon themes. The table below shows the cursor name used for each Qt::CursorShape value. If a cursor cannot be found using the name shown below, a standard X11 cursor will be used instead. Note: X11 does not provide appropriate cursors for all possible Qt::CursorShape values. It is possible that some cursors will be taken from the Xcursor theme, while others will use an internal bitmap cursor.

See also QWidget and GUI Design Handbook: Cursors.

Member Function Documentation

QCursor::QCursor(const QCursor &c)

Constructs a copy of the cursor c.

QCursor::QCursor(const QPixmap &pixmap, int hotX = -1, int hotY = -1)

Constructs a custom pixmap cursor.

pixmap is the image. It is usual to give it a mask (set using QPixmap::setMask()). hotX and hotY define the cursor's hot spot.

If hotX is negative, it is set to the pixmap().width()/2. If hotY is negative, it is set to the pixmap().height()/2.

Valid cursor sizes depend on the display hardware (or the underlying window system). We recommend using 32 x 32 cursors, because this size is supported on all platforms. Some platforms also support 16 x 16, 48 x 48, and 64 x 64 cursors.

See also QPixmap::QPixmap() and QPixmap::setMask().

QCursor::QCursor(const QBitmap &bitmap, const QBitmap &mask, int hotX = -1, int hotY = -1)

Constructs a custom bitmap cursor.

bitmap and mask make up the bitmap. hotX and hotY define the cursor's hot spot.

If hotX is negative, it is set to the bitmap().width()/2. If hotY is negative, it is set to the bitmap().height()/2.

The cursor bitmap (B) and mask (M) bits are combined like this:

  • B=1 and M=1 gives black.
  • B=0 and M=1 gives white.
  • B=0 and M=0 gives transparent.
  • B=1 and M=0 gives an XOR'd result under Windows, undefined results on all other platforms.

Use the global Qt color Qt::color0 to draw 0-pixels and Qt::color1 to draw 1-pixels in the bitmaps.

Valid cursor sizes depend on the display hardware (or the underlying window system). We recommend using 32 x 32 cursors, because this size is supported on all platforms. Some platforms also support 16 x 16, 48 x 48, and 64 x 64 cursors.

See also QBitmap::QBitmap() and QBitmap::setMask().

QCursor::QCursor(Qt::CursorShape shape)

Constructs a cursor with the specified shape.

See Qt::CursorShape for a list of shapes.

See also setShape().

QCursor::QCursor()

Constructs a cursor with the default arrow shape.

QCursor &QCursor::operator=(const QCursor &c)

Assigns c to this cursor and returns a reference to this cursor.

QCursor::~QCursor()

Destroys the cursor.

const QBitmap *QCursor::bitmap() const

Returns the cursor bitmap, or nullptr if it is one of the standard cursors.

QPoint QCursor::hotSpot() const

Returns the cursor hot spot, or (0, 0) if it is one of the standard cursors.

const QBitmap *QCursor::mask() const

Returns the cursor bitmap mask, or nullptr if it is one of the standard cursors.

QPixmap QCursor::pixmap() const

Returns the cursor pixmap. This is only valid if the cursor is a pixmap cursor.

void QCursor::setShape(Qt::CursorShape shape)

Sets the cursor to the shape identified by shape.

See Qt::CursorShape for the list of cursor shapes.

See also shape().

Qt::CursorShape QCursor::shape() const

Returns the cursor shape identifier. The return value is one of the Qt::CursorShape enum values (cast to an int).

See also setShape().

QVariant QCursor::operator QVariant() const

Returns the cursor as a QVariant.