Java java.awt.dnd Class DragSource（JDK8）

Field Detail

• DefaultCopyDrop

  public static final Cursor DefaultCopyDrop

  The default Cursor to use with a copy operation indicating that a drop is currently allowed. null if GraphicsEnvironment.isHeadless() returns true.

  See Also:

  GraphicsEnvironment.isHeadless()

• DefaultMoveDrop

  public static final Cursor DefaultMoveDrop

  The default Cursor to use with a move operation indicating that a drop is currently allowed. null if GraphicsEnvironment.isHeadless() returns true.

  See Also:

  GraphicsEnvironment.isHeadless()

• DefaultLinkDrop

  public static final Cursor DefaultLinkDrop

  The default Cursor to use with a link operation indicating that a drop is currently allowed. null if GraphicsEnvironment.isHeadless() returns true.

  See Also:

  GraphicsEnvironment.isHeadless()

• DefaultCopyNoDrop

  public static final Cursor DefaultCopyNoDrop

  The default Cursor to use with a copy operation indicating that a drop is currently not allowed. null if GraphicsEnvironment.isHeadless() returns true.

  See Also:

  GraphicsEnvironment.isHeadless()

• DefaultMoveNoDrop

  public static final Cursor DefaultMoveNoDrop

  The default Cursor to use with a move operation indicating that a drop is currently not allowed. null if GraphicsEnvironment.isHeadless() returns true.

  See Also:

  GraphicsEnvironment.isHeadless()

• DefaultLinkNoDrop

  public static final Cursor DefaultLinkNoDrop

  The default Cursor to use with a link operation indicating that a drop is currently not allowed. null if GraphicsEnvironment.isHeadless() returns true.

  See Also:

  GraphicsEnvironment.isHeadless()

Constructor Detail

• DragSource

  public DragSource()
             throws HeadlessException

  Creates a new DragSource.

  Throws:

  HeadlessException - if GraphicsEnvironment.isHeadless() returns true

  See Also:

  GraphicsEnvironment.isHeadless()

Method Detail

• getDefaultDragSource

  public static DragSource getDefaultDragSource()

  Gets the DragSource object associated with the underlying platform.

  Returns:

  the platform DragSource

  Throws:

  HeadlessException - if GraphicsEnvironment.isHeadless() returns true

  See Also:

  GraphicsEnvironment.isHeadless()

• isDragImageSupported

  public static boolean isDragImageSupported()

  Reports whether or not drag Image support is available on the underlying platform.

  Returns:

  if the Drag Image support is available on this platform

• startDrag

  public void startDrag(DragGestureEvent trigger,
                        Cursor dragCursor,
                        Image dragImage,
                        Point imageOffset,
                        Transferable transferable,
                        DragSourceListener dsl,
                        FlavorMap flavorMap)
                 throws InvalidDnDOperationException

  Start a drag, given the DragGestureEvent that initiated the drag, the initial Cursor to use, the Image to drag, the offset of the Image origin from the hotspot of the Cursor at the instant of the trigger, the Transferable subject data of the drag, the DragSourceListener, and the FlavorMap.

  Parameters:

  trigger - the DragGestureEvent that initiated the drag

  dragCursor - the initial Cursor for this drag operation or null for the default cursor handling; see DragSourceContext for more details on the cursor handling mechanism during drag and drop

  dragImage - the image to drag or null

  imageOffset - the offset of the Image origin from the hotspot of the Cursor at the instant of the trigger

  transferable - the subject data of the drag

  dsl - the DragSourceListener

  flavorMap - the FlavorMap to use, or null

  Throws:

  InvalidDnDOperationException - if the Drag and Drop system is unable to initiate a drag operation, or if the user attempts to start a drag while an existing drag operation is still executing

• startDrag

  public void startDrag(DragGestureEvent trigger,
                        Cursor dragCursor,
                        Transferable transferable,
                        DragSourceListener dsl,
                        FlavorMap flavorMap)
                 throws InvalidDnDOperationException

  Start a drag, given the DragGestureEvent that initiated the drag, the initial Cursor to use, the Transferable subject data of the drag, the DragSourceListener, and the FlavorMap.

  Parameters:

  trigger - the DragGestureEvent that initiated the drag

  dragCursor - the initial Cursor for this drag operation or null for the default cursor handling; see DragSourceContext for more details on the cursor handling mechanism during drag and drop

  transferable - the subject data of the drag

  dsl - the DragSourceListener

  flavorMap - the FlavorMap to use or null

  Throws:

  InvalidDnDOperationException - if the Drag and Drop system is unable to initiate a drag operation, or if the user attempts to start a drag while an existing drag operation is still executing

• startDrag

  public void startDrag(DragGestureEvent trigger,
                        Cursor dragCursor,
                        Image dragImage,
                        Point dragOffset,
                        Transferable transferable,
                        DragSourceListener dsl)
                 throws InvalidDnDOperationException

  Start a drag, given the DragGestureEvent that initiated the drag, the initial Cursor to use, the Image to drag, the offset of the Image origin from the hotspot of the Cursor at the instant of the trigger, the subject data of the drag, and the DragSourceListener.

  Parameters:

  trigger - the DragGestureEvent that initiated the drag

  dragCursor - the initial Cursor for this drag operation or null for the default cursor handling; see DragSourceContext for more details on the cursor handling mechanism during drag and drop

  dragImage - the Image to drag or null

  dragOffset - the offset of the Image origin from the hotspot of the Cursor at the instant of the trigger

  transferable - the subject data of the drag

  dsl - the DragSourceListener

  Throws:

  InvalidDnDOperationException - if the Drag and Drop system is unable to initiate a drag operation, or if the user attempts to start a drag while an existing drag operation is still executing

• startDrag

  public void startDrag(DragGestureEvent trigger,
                        Cursor dragCursor,
                        Transferable transferable,
                        DragSourceListener dsl)
                 throws InvalidDnDOperationException

  Start a drag, given the DragGestureEvent that initiated the drag, the initial Cursor to use, the Transferable subject data of the drag, and the DragSourceListener.

  Parameters:

  trigger - the DragGestureEvent that initiated the drag

  dragCursor - the initial Cursor for this drag operation or null for the default cursor handling; see DragSourceContext class for more details on the cursor handling mechanism during drag and drop

  transferable - the subject data of the drag

  dsl - the DragSourceListener

  Throws:

  InvalidDnDOperationException - if the Drag and Drop system is unable to initiate a drag operation, or if the user attempts to start a drag while an existing drag operation is still executing

• createDragSourceContext

  protected DragSourceContext createDragSourceContext(java.awt.dnd.peer.DragSourceContextPeer dscp,
                                                      DragGestureEvent dgl,
                                                      Cursor dragCursor,
                                                      Image dragImage,
                                                      Point imageOffset,
                                                      Transferable t,
                                                      DragSourceListener dsl)

  Creates the DragSourceContext to handle the current drag operation.

  To incorporate a new DragSourceContext subclass, subclass DragSource and override this method.

  If dragImage is null, no image is used to represent the drag over feedback for this drag operation, but NullPointerException is not thrown.

  If dsl is null, no drag source listener is registered with the created DragSourceContext, but NullPointerException is not thrown.

  Parameters:

  dscp - The DragSourceContextPeer for this drag

  dgl - The DragGestureEvent that triggered the drag

  dragCursor - The initial Cursor for this drag operation or null for the default cursor handling; see DragSourceContext class for more details on the cursor handling mechanism during drag and drop

  dragImage - The Image to drag or null

  imageOffset - The offset of the Image origin from the hotspot of the cursor at the instant of the trigger

  t - The subject data of the drag

  dsl - The DragSourceListener

  Returns:

  the DragSourceContext

  Throws:

  NullPointerException - if dscp is null

  NullPointerException - if dgl is null

  NullPointerException - if dragImage is not null and imageOffset is null

  NullPointerException - if t is null

  IllegalArgumentException - if the Component associated with the trigger event is null.

  IllegalArgumentException - if the DragSource for the trigger event is null.

  IllegalArgumentException - if the drag action for the trigger event is DnDConstants.ACTION_NONE.

  IllegalArgumentException - if the source actions for the DragGestureRecognizer associated with the trigger event are equal to DnDConstants.ACTION_NONE.

• getFlavorMap

  public FlavorMap getFlavorMap()

  This method returns the FlavorMap for this DragSource.

  Returns:

  the FlavorMap for this DragSource

• createDragGestureRecognizer

  public <T extends DragGestureRecognizer> T createDragGestureRecognizer(Class<T> recognizerAbstractClass,
                                                                         Component c,
                                                                         int actions,
                                                                         DragGestureListener dgl)

  Creates a new DragGestureRecognizer that implements the specified abstract subclass of DragGestureRecognizer, and sets the specified Component and DragGestureListener on the newly created object.

  Parameters:

  recognizerAbstractClass - the requested abstract type

  actions - the permitted source drag actions

  c - the Component target

  dgl - the DragGestureListener to notify

  Returns:

  the new DragGestureRecognizer or null if the Toolkit.createDragGestureRecognizer method has no implementation available for the requested DragGestureRecognizer subclass and returns null

• createDefaultDragGestureRecognizer

  public DragGestureRecognizer createDefaultDragGestureRecognizer(Component c,
                                                                  int actions,
                                                                  DragGestureListener dgl)

  Creates a new DragGestureRecognizer that implements the default abstract subclass of DragGestureRecognizer for this DragSource, and sets the specified Component and DragGestureListener on the newly created object. For this DragSource the default is MouseDragGestureRecognizer.

  Parameters:

  c - the Component target for the recognizer

  actions - the permitted source actions

  dgl - the DragGestureListener to notify

  Returns:

  the new DragGestureRecognizer or null if the Toolkit.createDragGestureRecognizer method has no implementation available for the requested DragGestureRecognizer subclass and returns null

• addDragSourceListener

  public void addDragSourceListener(DragSourceListener dsl)

  Adds the specified DragSourceListener to this DragSource to receive drag source events during drag operations intiated with this DragSource. If a null listener is specified, no action is taken and no exception is thrown.

  Parameters:

  dsl - the DragSourceListener to add

  Since:

  1.4

  See Also:

  removeDragSourceListener(java.awt.dnd.DragSourceListener), getDragSourceListeners()

• removeDragSourceListener

  public void removeDragSourceListener(DragSourceListener dsl)

  Removes the specified DragSourceListener from this DragSource. If a null listener is specified, no action is taken and no exception is thrown. If the listener specified by the argument was not previously added to this DragSource, no action is taken and no exception is thrown.

  Parameters:

  dsl - the DragSourceListener to remove

  Since:

  1.4

  See Also:

  addDragSourceListener(java.awt.dnd.DragSourceListener), getDragSourceListeners()

• getDragSourceListeners

  public DragSourceListener[] getDragSourceListeners()

  Gets all the DragSourceListeners registered with this DragSource.

  Returns:

  all of this DragSource's DragSourceListeners or an empty array if no such listeners are currently registered

  Since:

  1.4

  See Also:

  addDragSourceListener(java.awt.dnd.DragSourceListener), removeDragSourceListener(java.awt.dnd.DragSourceListener)

• addDragSourceMotionListener

  public void addDragSourceMotionListener(DragSourceMotionListener dsml)

  Adds the specified DragSourceMotionListener to this DragSource to receive drag motion events during drag operations intiated with this DragSource. If a null listener is specified, no action is taken and no exception is thrown.

  Parameters:

  dsml - the DragSourceMotionListener to add

  Since:

  1.4

  See Also:

  removeDragSourceMotionListener(java.awt.dnd.DragSourceMotionListener), getDragSourceMotionListeners()

• removeDragSourceMotionListener

  public void removeDragSourceMotionListener(DragSourceMotionListener dsml)

  Removes the specified DragSourceMotionListener from this DragSource. If a null listener is specified, no action is taken and no exception is thrown. If the listener specified by the argument was not previously added to this DragSource, no action is taken and no exception is thrown.

  Parameters:

  dsml - the DragSourceMotionListener to remove

  Since:

  1.4

  See Also:

  addDragSourceMotionListener(java.awt.dnd.DragSourceMotionListener), getDragSourceMotionListeners()

• getDragSourceMotionListeners

  public DragSourceMotionListener[] getDragSourceMotionListeners()

  Gets all of the DragSourceMotionListeners registered with this DragSource.

  Returns:

  all of this DragSource's DragSourceMotionListeners or an empty array if no such listeners are currently registered

  Since:

  1.4

  See Also:

  addDragSourceMotionListener(java.awt.dnd.DragSourceMotionListener), removeDragSourceMotionListener(java.awt.dnd.DragSourceMotionListener)

• getListeners

  public <T extends EventListener> T[] getListeners(Class<T> listenerType)

  Gets all the objects currently registered as FooListeners upon this DragSource. FooListeners are registered using the addFooListener method.

  Parameters:

  listenerType - the type of listeners requested; this parameter should specify an interface that descends from java.util.EventListener

  Returns:

  an array of all objects registered as FooListeners on this DragSource, or an empty array if no such listeners have been added

  Throws:

  ClassCastException - if listenerType doesn't specify a class or interface that implements java.util.EventListener

  Since:

  1.4

  See Also:

  getDragSourceListeners(), getDragSourceMotionListeners()

• getDragThreshold

  public static int getDragThreshold()

  Returns the drag gesture motion threshold. The drag gesture motion threshold defines the recommended behavior for MouseDragGestureRecognizers.

  If the system property awt.dnd.drag.threshold is set to a positive integer, this method returns the value of the system property; otherwise if a pertinent desktop property is available and supported by the implementation of the Java platform, this method returns the value of that property; otherwise this method returns some default value. The pertinent desktop property can be queried using java.awt.Toolkit.getDesktopProperty("DnD.gestureMotionThreshold").

  Returns:

  the drag gesture motion threshold

  Since:

  1.5

  See Also:

  MouseDragGestureRecognizer