Class Cursor


  • public final class Cursor
    extends Resource
    Instances of this class manage operating system resources that specify the appearance of the on-screen pointer. To create a cursor you specify the device and either a simple cursor style describing one of the standard operating system provided cursors or the image and mask data for the desired appearance.

    Application code must explicitly invoke the Cursor.dispose() method to release the operating system resources managed by each instance when those instances are no longer required.

    Styles:
    CURSOR_ARROW, CURSOR_WAIT, CURSOR_CROSS, CURSOR_APPSTARTING, CURSOR_HELP, CURSOR_SIZEALL, CURSOR_SIZENESW, CURSOR_SIZENS, CURSOR_SIZENWSE, CURSOR_SIZEWE, CURSOR_SIZEN, CURSOR_SIZES, CURSOR_SIZEE, CURSOR_SIZEW, CURSOR_SIZENE, CURSOR_SIZESE, CURSOR_SIZESW, CURSOR_SIZENW, CURSOR_UPARROW, CURSOR_IBEAM, CURSOR_NO, CURSOR_HAND

    Note: Only one of the above styles may be specified.

    See Also:
    Cursor snippets, Sample code and further information
    • Field Summary

      Fields 
      Modifier and Type Field Description
      long handle
      the handle to the OS cursor resource (Warning: This field is platform dependent)
    • Constructor Summary

      Constructors 
      Constructor Description
      Cursor​(Device device, int style)
      Constructs a new cursor given a device and a style constant describing the desired cursor appearance.
      Cursor​(Device device, ImageData source, int hotspotX, int hotspotY)
      Constructs a new cursor given a device, image data describing the desired cursor appearance, and the x and y coordinates of the hotspot (that is, the point within the area covered by the cursor which is considered to be where the on-screen pointer is "pointing").
      Cursor​(Device device, ImageData source, ImageData mask, int hotspotX, int hotspotY)
      Constructs a new cursor given a device, image and mask data describing the desired cursor appearance, and the x and y coordinates of the hotspot (that is, the point within the area covered by the cursor which is considered to be where the on-screen pointer is "pointing").
    • Field Detail

      • handle

        public long handle
        the handle to the OS cursor resource (Warning: This field is platform dependent)

        IMPORTANT: This field is not part of the SWT public API. It is marked public only so that it can be shared within the packages provided by SWT. It is not available on all platforms and should never be accessed from application code.

        Restriction:
        This field is not intended to be referenced by clients.
    • Constructor Detail

      • Cursor

        public Cursor​(Device device,
                      ImageData source,
                      ImageData mask,
                      int hotspotX,
                      int hotspotY)
        Constructs a new cursor given a device, image and mask data describing the desired cursor appearance, and the x and y coordinates of the hotspot (that is, the point within the area covered by the cursor which is considered to be where the on-screen pointer is "pointing").

        The mask data is allowed to be null, but in this case the source must be an ImageData representing an icon that specifies both color data and mask data.

        You must dispose the cursor when it is no longer required.

        Parameters:
        device - the device on which to allocate the cursor
        source - the color data for the cursor
        mask - the mask data for the cursor (or null)
        hotspotX - the x coordinate of the cursor's hotspot
        hotspotY - the y coordinate of the cursor's hotspot
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if device is null and there is no current device
        • ERROR_NULL_ARGUMENT - if the source is null
        • ERROR_NULL_ARGUMENT - if the mask is null and the source does not have a mask
        • ERROR_INVALID_ARGUMENT - if the source and the mask are not the same size, or if the hotspot is outside the bounds of the image
        SWTError -
        • ERROR_NO_HANDLES - if a handle could not be obtained for cursor creation
        See Also:
        Resource.dispose()
      • Cursor

        public Cursor​(Device device,
                      ImageData source,
                      int hotspotX,
                      int hotspotY)
        Constructs a new cursor given a device, image data describing the desired cursor appearance, and the x and y coordinates of the hotspot (that is, the point within the area covered by the cursor which is considered to be where the on-screen pointer is "pointing").

        You must dispose the cursor when it is no longer required.

        Parameters:
        device - the device on which to allocate the cursor
        source - the image data for the cursor
        hotspotX - the x coordinate of the cursor's hotspot
        hotspotY - the y coordinate of the cursor's hotspot
        Throws:
        IllegalArgumentException -
        • ERROR_NULL_ARGUMENT - if device is null and there is no current device
        • ERROR_NULL_ARGUMENT - if the image is null
        • ERROR_INVALID_ARGUMENT - if the hotspot is outside the bounds of the image
        SWTError -
        • ERROR_NO_HANDLES - if a handle could not be obtained for cursor creation
        Since:
        3.0
        See Also:
        Resource.dispose()
    • Method Detail

      • equals

        public boolean equals​(Object object)
        Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
        Overrides:
        equals in class Object
        Parameters:
        object - the object to compare with this object
        Returns:
        true if the object is the same as this object and false otherwise
        See Also:
        hashCode()
      • hashCode

        public int hashCode()
        Returns an integer hash code for the receiver. Any two objects that return true when passed to equals must return the same value for this method.
        Overrides:
        hashCode in class Object
        Returns:
        the receiver's hash
        See Also:
        equals(java.lang.Object)
      • isDisposed

        public boolean isDisposed()
        Returns true if the cursor has been disposed, and false otherwise.

        This method gets the dispose state for the cursor. When a cursor has been disposed, it is an error to invoke any other method (except Resource.dispose()) using the cursor.

        Specified by:
        isDisposed in class Resource
        Returns:
        true when the cursor is disposed and false otherwise
      • toString

        public String toString()
        Returns a string containing a concise, human-readable description of the receiver.
        Overrides:
        toString in class Object
        Returns:
        a string representation of the receiver
      • win32_new

        public static Cursor win32_new​(Device device,
                                       int handle)
        Invokes platform specific functionality to allocate a new cursor.

        IMPORTANT: This method is not part of the public API for Cursor. It is marked public only so that it can be shared within the packages provided by SWT. It is not available on all platforms, and should never be called from application code.

        Parameters:
        device - the device on which to allocate the color
        handle - the handle for the cursor
        Returns:
        a new cursor object containing the specified device and handle
        Restriction:
        This method is not intended to be referenced by clients.