Class AbstractTool

java.lang.Object
org.eclipse.gef.util.FlagSupport
org.eclipse.gef.tools.AbstractTool
All Implemented Interfaces:
RequestConstants, Tool
Direct Known Subclasses:
MarqueeSelectionTool, SimpleDragTracker, TargetingTool

public abstract class AbstractTool extends FlagSupport implements Tool, RequestConstants
The base implementation for Tools. The base implementation provides a framework for a state machine which processes mouse and keyboard input. The state machine consists of a series of states identified by ints. Each mouse or keyboard event results in a transition, sometimes to the same state in which the input was received. The interesting transitions have corresponding actions assigned to them, such as handleDragStarted().

The base implementation performs no state transitions by default, but does route events to different method handlers based on state. It is up to subclasses to set the appropriate states.

There are two broad "categories" of methods on AbstractTool. There are the methods defined on the Tool interface which handle the job of receiving raw user input. For example, mouseDrag(MouseEvent, EditPartViewer). Then, there are the methods which correspond to higher-level interpretation of these events, such as handleDragInProgress(), which is called from mouseMove(...), but only when the drag threshold has been passed. These methods are generally more subclass-friendly. Subclasses should not override the methods which receive raw input.

  • Field Details

    • PROPERTY_UNLOAD_WHEN_FINISHED

      public static final Object PROPERTY_UNLOAD_WHEN_FINISHED
      The property to be used in setProperties(Map) for setUnloadWhenFinished(boolean)
    • MAX_FLAG

      protected static final int MAX_FLAG
      The highest-bit flag being used.
      See Also:
    • MAX_STATE

      protected static final int MAX_STATE
      The maximum state flag defined by this class
      See Also:
    • MOUSE_BUTTON1

      protected static final int MOUSE_BUTTON1
      Deprecated.
      Use SWT.BUTTON1 instead.
      constant used for mouse button 1.
      See Also:
    • MOUSE_BUTTON2

      protected static final int MOUSE_BUTTON2
      Deprecated.
      Use SWT.BUTTON2 instead.
      constant used for mouse button 2.
      See Also:
    • MOUSE_BUTTON3

      protected static final int MOUSE_BUTTON3
      Deprecated.
      Use SWT.BUTTON3 instead.
      constant used for mouse button 3.
      See Also:
    • MOUSE_BUTTON_ANY

      protected static final int MOUSE_BUTTON_ANY
      Deprecated.
      Use SWT.BUTTON_MASK instead.
      constant used to indicate any of the mouse buttons.
    • STATE_ACCESSIBLE_DRAG

      protected static final int STATE_ACCESSIBLE_DRAG
      The state indicating that the keyboard is being used to perform a drag that is normally done using the mouse.
      See Also:
    • STATE_ACCESSIBLE_DRAG_IN_PROGRESS

      protected static final int STATE_ACCESSIBLE_DRAG_IN_PROGRESS
      The state indicating that a keyboard drag is in progress. The threshold for keyboard drags is non-existent, so this state would be entered very quickly.
      See Also:
    • STATE_DRAG

      protected static final int STATE_DRAG
      The state indicating that one or more buttons are pressed, but the user has not moved past the drag threshold. Many tools will do nothing during this state but wait until STATE_DRAG_IN_PROGRESS is entered.
      See Also:
    • STATE_DRAG_IN_PROGRESS

      protected static final int STATE_DRAG_IN_PROGRESS
      The state indicating that the drag detection theshold has been passed, and a drag is in progress.
      See Also:
    • STATE_INITIAL

      protected static final int STATE_INITIAL
      The first state that a tool is in. The tool will generally be in this state immediately following activate().
      See Also:
    • STATE_INVALID

      protected static final int STATE_INVALID
      The state indicating that an input event has invalidated the interaction. For example, during a mouse drag, pressing additional mouse button might invalidate the drag.
      See Also:
    • STATE_TERMINAL

      protected static final int STATE_TERMINAL
      The final state for a tool to be in. Once a tool reaches this state, it will not change states until it is activated() again.
      See Also:
  • Constructor Details

    • AbstractTool

      public AbstractTool()
  • Method Details

    • acceptArrowKey

      protected boolean acceptArrowKey(KeyEvent e)
      Returns true if the event corresponds to an arrow key with the appropriate modifiers and if the system is in a state where the arrow key should be accepted.
      Parameters:
      e - the key event
      Returns:
      true if the arrow key should be accepted by this tool
      Since:
      3.4
    • activate

      public void activate()
      Activates the tool. Any initialization should be performed here. This method is called when a tool is selected.
      Specified by:
      activate in interface Tool
      See Also:
    • addFeedback

      protected void addFeedback(org.eclipse.draw2d.IFigure figure)
      Convenience method to add the given figure to the feedback layer.
      Parameters:
      figure - the feedback being added
    • applyProperty

      protected void applyProperty(Object key, Object value)
      This method is invoked from setProperties(Map). Sub-classes can override to add support for more properties. This method should fail silently in case of any error.

      AbstractTool uses introspection to match any keys with properties. For instance, the key "defaultCursor" would lead to the invocation of setDefaultCursor(Cursor) with the provided value.

      Parameters:
      key - the key; may be null
      value - the new value
      Since:
      3.1
      See Also:
    • calculateCursor

      protected Cursor calculateCursor()
      Returns the appropriate cursor for the tools current state. If the tool is in its terminal state, null is returned. Otherwise, either the default or disabled cursor is returned, based on the existence of a current command, and whether that current command is executable.

      Subclasses may override or extend this method to calculate the appropriate cursor based on other conditions.

      Returns:
      null or a cursor to be displayed.
      See Also:
    • commitDrag

      public void commitDrag()
      Added for compatibility. DragTracker.commitDrag() was added for accessibility reasons. Since all tool implementations must inherit from this base class, then implementing this method here avoids breaking subclasses that implemented the DragTracker interface.
    • createOperationSet

      protected List createOperationSet()
      Returns a new List of editparts that this tool is operating on. This method is called once during getOperationSet(), and its result is cached.

      By default, the operations set is the current viewer's entire selection. Subclasses may override this method to filter or alter the operation set as necessary.

      Returns:
      a list of editparts being operated on
    • deactivate

      public void deactivate()
      Deactivates the tool. This method is called whenever the user switches to another tool. Use this method to do some clean-up when the tool is switched. The abstract tool allows cursors for viewers to be changed. When the tool is deactivated it must revert to normal the cursor of the last tool it changed.
      Specified by:
      deactivate in interface Tool
      See Also:
    • debug

      protected void debug(String message)
      Deprecated.
      Prints a string in the GEF Debug console if the Tools debug option is selected.
      Parameters:
      message - a message for the debug trace tool
    • executeCommand

      protected void executeCommand(Command command)
      Executes the given command on the command stack.
      Parameters:
      command - the command to execute
      Since:
      3.1
    • executeCurrentCommand

      protected void executeCurrentCommand()
      Execute the currently active command.
    • focusGained

      public void focusGained(FocusEvent event, EditPartViewer viewer)
      Called when a viewer that the editor controls gains focus.
      Specified by:
      focusGained in interface Tool
      Parameters:
      event - The SWT focus event
      viewer - The viewer that the focus event is over.
    • focusLost

      public void focusLost(FocusEvent event, EditPartViewer viewer)
      Called when a viewer that the editor controls loses focus.
      Specified by:
      focusLost in interface Tool
      Parameters:
      event - The SWT focus event
      viewer - The viewer that the focus event is over.
    • getCommand

      protected Command getCommand()
      Returns a new, updated command based on the tool's current properties. The default implementation returns an unexecutable command. Some tools do not work commands and the model, but simply change the viewer's state in some way.
      Returns:
      a newly obtained command
    • getCommandName

      protected abstract String getCommandName()
      Returns the identifier of the command that is being sought. This name is also the named that will be logged in the debug view.
      Returns:
      the identifier for the command
    • getCurrentCommand

      protected Command getCurrentCommand()
      Returns the currently cached command.
      Returns:
      the current command
      See Also:
    • getCurrentInput

      protected AbstractTool.Input getCurrentInput()
      Returns the input object encapsulating the current mouse and keyboard state.
      Returns:
      the current input
    • getCurrentViewer

      protected EditPartViewer getCurrentViewer()
      Return the viewer that the tool is currently receiving input from, or null. The last viewer to dispatch an event is defined as the current viewer. Current viewer is automatically updated as events are received, and is set to null on deactivate().
      Returns:
      the current viewer
    • getDebugName

      protected String getDebugName()
      Returns the debug name for this tool.
      Returns:
      the debug name
    • getDebugNameForState

      protected String getDebugNameForState(int state)
      Returns a String representation of the given state for debug purposes.
      Parameters:
      state - the state
      Returns:
      the string for the given state
    • getDefaultCursor

      protected Cursor getDefaultCursor()
      Returns the cursor used under normal conditions.
      Returns:
      the default cursor
      See Also:
    • getDisabledCursor

      protected Cursor getDisabledCursor()
      Returns the cursor used under abnormal conditions.
      Returns:
      the disabled cursor
      See Also:
    • getDomain

      protected EditDomain getDomain()
      Returns the EditDomain. A tool is told its EditDomain when it becomes active. A tool may need to know its edit domain prior to receiving any events from any of that domain's viewers.
      Returns:
      the editdomain
    • getDragMoveDelta

      protected org.eclipse.draw2d.geometry.Dimension getDragMoveDelta()
      Return the number of pixels that the mouse has been moved since that drag was started. The drag start is determined by where the mouse button was first pressed.
      Returns:
      the drag delta
      See Also:
    • getLocation

      protected org.eclipse.draw2d.geometry.Point getLocation()
      Returns the current x, y position of the mouse cursor.
      Returns:
      the mouse location
    • getOperationSet

      protected List getOperationSet()
      Lazily creates and returns the list of editparts on which the tool operates. The list is initially null, in which case createOperationSet() is called, and its results cached until the tool is deactivated.
      Returns:
      the operation set.
    • getStartLocation

      protected org.eclipse.draw2d.geometry.Point getStartLocation()
      Returns the starting mouse location for the current tool operation. This is typically the mouse location where the user first pressed a mouse button. This is important for tools that interpret mouse drags.
      Returns:
      the start location
    • getState

      protected int getState()
      Returns the tool's current state.
      Returns:
      the current state
    • handleButtonDown

      protected boolean handleButtonDown(int button)
      Called when the mouse button has been pressed. By default, nothing happens and false is returned. Subclasses may override this method to interpret the meaning of a mouse down. Returning true indicates that the button down was handled in some way.
      Parameters:
      button - which button went down
      Returns:
      true if the buttonDown was handled
    • handleButtonUp

      protected boolean handleButtonUp(int button)
      Called when the mouse button has been released. By default, nothing happens and false is returned. Subclasses may override this method to interpret the mouse up. Returning true indicates that the mouse up was handled in some way.
      Parameters:
      button - the button being released
      Returns:
      true if the button up was handled
      See Also:
    • handleCommandStackChanged

      protected boolean handleCommandStackChanged()
      Called when the command stack has changed, for instance, when a delete or undo command has been executed. By default, state is set to STATE_INVALID and handleInvalidInput is called. Subclasses may override this method to change what happens when the command stack changes. Returning true indicates that the change was handled in some way.
      Returns:
      true if the change was handled in some way
    • handleDoubleClick

      protected boolean handleDoubleClick(int button)
      Called when a mouse double-click occurs. By default, nothing happens and false is returned. Subclasses may override this method to interpret double-clicks. Returning true indicates that the event was handled in some way.
      Parameters:
      button - which button was double-clicked
      Returns:
      true if the event was handled
      See Also:
    • handleDrag

      protected boolean handleDrag()
      Called whenever the mouse is being dragged. This method continues to be called even once handleDragInProgress() starts getting called. By default, nothing happens, and false is returned. Subclasses may override this method to interpret a drag. Returning true indicates that the drag was handled in some way.
      Returns:
      true if the drag is handled
      See Also:
    • handleDragInProgress

      protected boolean handleDragInProgress()
      Called whenever a mouse is being dragged and the drag threshold has been exceeded. Prior to the drag threshold being exceeded, only handleDrag() is called. This method gets called repeatedly for every mouse move during the drag. By default, nothing happens and false is returned. Subclasses may override this method to interpret the drag. Returning true indicates that the drag was handled.
      Returns:
      true if the drag was handled
      See Also:
    • handleDragStarted

      protected boolean handleDragStarted()
      Called only one time during a drag when the drag threshold has been exceeded. By default, nothing happens and false is returned. Subclasses may override to interpret the drag starting. Returning true indicates that the event was handled.
      Returns:
      true if the drag starting was handled
      See Also:
    • handleFinished

      protected void handleFinished()
      Called when the current tool operation is to be completed. In other words, the "state machine" and has accepted the sequence of input (i.e. the mouse gesture). By default, the tool will either reactivate itself, or ask the edit domain to load the default tool.

      Subclasses should extend this method to first do whatever it is that the tool does, and then call super.

      See Also:
    • handleFocusGained

      protected boolean handleFocusGained()
      Handles high-level processing of a focus gained event. By default, nothing happens and false is returned. Subclasses may override this method to interpret the focus gained event. Return true to indicate that the event was processed.
      Returns:
      true if the event was handled
      See Also:
    • handleFocusLost

      protected boolean handleFocusLost()
      Handles high-level processing of a focus lost event. By default, nothing happens and false is returned. Subclasses may override this method to interpret the focus lost event. Return true to indicate that the event was processed.
      Returns:
      true if the event was handled
      See Also:
    • handleHover

      protected boolean handleHover()
      Handles high-level processing of a mouse hover event. By default, nothing happens and false is returned. Subclasses may override this method to interpret the hover. Return true to indicate that the hover was handled.
      Returns:
      true if the hover was handled
      See Also:
    • handleInvalidInput

      protected boolean handleInvalidInput()
      Called when invalid input is encountered. The state does not change, so the caller must set the state to STATE_INVALID.
      Returns:
      true
    • handleKeyDown

      protected boolean handleKeyDown(KeyEvent e)
      Handles high-level processing of a key down event. By default, the KeyEvent is checked to see if it is the ESCAPE key. If so, the domain's default tool is reloaded, and true is returned. Subclasses may extend this method to interpret additional key down events. Returns true if the given key down was handled.
      Parameters:
      e - the key event
      Returns:
      true if the key down was handled.
      See Also:
    • handleKeyTraversed

      protected void handleKeyTraversed(TraverseEvent event)
      Override to process a traverse event. If the event's doit field is set to false, the traversal will be prevented from occurring. Otherwise, a traverse will occur.
      Parameters:
      event - the SWT traverse event
      Since:
      3.1
    • handleKeyUp

      protected boolean handleKeyUp(KeyEvent e)
      Handles high-level processing of a key up event. By default, does nothing and returns false. Subclasses may extend this method to process key up events. Returns true if the key up was processed in some way.
      Parameters:
      e - the key event
      Returns:
      true if the event was handled
      See Also:
    • handleMove

      protected boolean handleMove()
      Handles high-level processing of a mouse move. By default, does nothing and returns false. Subclasses may extend this method to process mouse moves. Returns true if the mouse move was processed.
      Returns:
      true if the mouse move was handled
      See Also:
    • handleNativeDragFinished

      protected boolean handleNativeDragFinished(DragSourceEvent event)
      Handles when a native drag has ended. By default, does nothing and returns false. Subclasses may extend this method to process native drags ending.
      Parameters:
      event - the drag event
      Returns:
      true if the native drag finished was handled
    • handleNativeDragStarted

      protected boolean handleNativeDragStarted(DragSourceEvent event)
      Handles when a native drag has started. By default, does nothing and returns false. Subclasses may extend this method to process native drag starts.

      When a native drag starts, all subsequent mouse events will not be received, including the mouseUp event. The only event that will be received is the drag finished event.

      Parameters:
      event - the drag event
      Returns:
      true if the native drag start was handled
    • handleViewerEntered

      protected boolean handleViewerEntered()
      Called when the mouse enters an EditPartViewer. By default, does nothing and returns false. Subclasses may extend this method to process the viewer enter. Returns true to indicate if the viewer entered was process in some way.
      Returns:
      true if the viewer entered was handled
    • handleViewerExited

      protected boolean handleViewerExited()
      Called when the mouse exits an EditPartViewer. By default, does nothing and returns false. Subclasses may extend this method to process viewer exits. Returns true to indicate if the viewer exited was process in some way.
      Returns:
      true if the viewer exited was handled
    • isActive

      protected boolean isActive()
      Returns true if the tool is active.
      Returns:
      true if active
    • isHoverActive

      protected boolean isHoverActive()
      Returns true if the tool is hovering.
      Returns:
      true if hovering
    • isInState

      protected boolean isInState(int state)
      Returns true if the tool is in the given state.
      Parameters:
      state - the state being queried
      Returns:
      true if the tool is in the given state
    • isViewerImportant

      protected boolean isViewerImportant(EditPartViewer viewer)
      Default implementation always returns true. Sub-classes may override.
      Parameters:
      viewer - the viewer where the event occured
      Returns:
      true if this tool is interested in events occuring in the given viewer; false otherwise
      Since:
      3.1
    • keyDown

      public void keyDown(KeyEvent evt, EditPartViewer viewer)
      Receives a KeyDown event for the given viewer. Subclasses wanting to handle this event should override handleKeyDown(KeyEvent).
      Specified by:
      keyDown in interface Tool
      Parameters:
      evt - the key event
      viewer - the originating viewer
    • keyTraversed

      public void keyTraversed(TraverseEvent event, EditPartViewer viewer)
      Receives a traversal event for the given viewer. Subclasses wanting to handle this event should override handleKeyTraversed(TraverseEvent).
      Specified by:
      keyTraversed in interface Tool
      Parameters:
      event - the traverse event
      viewer - the originating viewer
    • keyUp

      public void keyUp(KeyEvent evt, EditPartViewer viewer)
      Receives a KeyUp event for the given viewer. Subclasses wanting to handle this event should override handleKeyUp(KeyEvent).
      Specified by:
      keyUp in interface Tool
      Parameters:
      evt - the key event
      viewer - the originating viewer
    • mouseDoubleClick

      public void mouseDoubleClick(MouseEvent me, EditPartViewer viewer)
      Handles mouse double click events within a viewer. Subclasses wanting to handle this event should override handleDoubleClick(int).
      Specified by:
      mouseDoubleClick in interface Tool
      Parameters:
      me - the mouse event
      viewer - the originating viewer
    • mouseDown

      public void mouseDown(MouseEvent me, EditPartViewer viewer)
      Handles mouse down events within a viewer. Subclasses wanting to handle this event should override handleButtonDown(int).
      Specified by:
      mouseDown in interface Tool
      Parameters:
      me - the mouse event
      viewer - the originating viewer
    • mouseDrag

      public void mouseDrag(MouseEvent me, EditPartViewer viewer)
      Handles mouse drag events within a viewer. Subclasses wanting to handle this event should override handleDrag() and/or handleDragInProgress().
      Specified by:
      mouseDrag in interface Tool
      Parameters:
      me - the mouse event
      viewer - the originating viewer
    • mouseHover

      public void mouseHover(MouseEvent me, EditPartViewer viewer)
      Handles mouse hover event. within a viewer. Subclasses wanting to handle this event should override handleHover().
      Specified by:
      mouseHover in interface Tool
      Parameters:
      me - the mouse event
      viewer - the originating viewer
      See Also:
    • mouseMove

      public void mouseMove(MouseEvent me, EditPartViewer viewer)
      Handles mouse moves (if the mouse button is up) within a viewer. Subclasses wanting to handle this event should override handleMove().
      Specified by:
      mouseMove in interface Tool
      Parameters:
      me - the mouse event
      viewer - the originating viewer
      See Also:
    • mouseUp

      public void mouseUp(MouseEvent me, EditPartViewer viewer)
      Handles mouse up within a viewer. Subclasses wanting to handle this event should override handleButtonUp(int).
      Specified by:
      mouseUp in interface Tool
      Parameters:
      me - the mouse event
      viewer - the originating viewer
    • mouseWheelScrolled

      public void mouseWheelScrolled(Event event, EditPartViewer viewer)
      Handles mouse-wheel scrolling for a viewer. Sub-classes may override as needed. The default implementation delegates to performViewerMouseWheel(Event, EditPartViewer) IFF the tool is in the initial state. Mouse-wheel events generated at other times are ignored.
      Specified by:
      mouseWheelScrolled in interface Tool
      Parameters:
      event - the SWT scroll event
      viewer - the originating viewer
      See Also:
    • movedPastThreshold

      protected boolean movedPastThreshold()
      Returns true if the threshold has been exceeded during a mouse drag.
      Returns:
      true if the threshold has been exceeded
    • nativeDragFinished

      public void nativeDragFinished(DragSourceEvent event, EditPartViewer viewer)
      Description copied from interface: Tool
      Called when a native drag ends on a Viewer. This event is important to Tools because mouseUp(..) will not occur once a native drag has started. The Tool should correct its state to handle this lost Event.
      Specified by:
      nativeDragFinished in interface Tool
      Parameters:
      event - the SWT DragSourceEvent
      viewer - the Viewer on which a native drag started
      See Also:
    • nativeDragStarted

      public void nativeDragStarted(DragSourceEvent event, EditPartViewer viewer)
      Description copied from interface: Tool
      Called when a native drag begins on a Viewer. This event is important to Tools because mouseUp(..) will not occur once a native drag has started. The Tool should correct its state to handle this lost Event.
      Specified by:
      nativeDragStarted in interface Tool
      Parameters:
      event - the SWT DragSourceEvent
      viewer - the Viewer on which a native drag started
      See Also:
    • performViewerMouseWheel

      protected void performViewerMouseWheel(Event event, EditPartViewer viewer)
      Delegates mouse-wheel event handling to registered MouseWheelHandlers based on the given Event's statemask. Does nothing if there are no matching handlers found.
      Parameters:
      event - the SWT scroll event
      viewer - the originating viewer
      Since:
      3.1
    • placeMouseInViewer

      protected void placeMouseInViewer(org.eclipse.draw2d.geometry.Point p)
      Places the mouse in the viewer based on the point given. If the point given is outside the viewer, then the mouse is placed in the location nearest the given point but within the viewer.
      Parameters:
      p - the point
      Since:
      3.4
    • reactivate

      protected void reactivate()
      Calls deactivate() and then activate().
    • refreshCursor

      protected void refreshCursor()
      Sets the cursor being displayed to the appropriate cursor. If the tool is active, the current cursor being displayed is updated by calling calculateCursor().
    • releaseToolCapture

      protected void releaseToolCapture()
      Releases tool capture.
      See Also:
    • removeFeedback

      protected void removeFeedback(org.eclipse.draw2d.IFigure figure)
      Convenience method to removes a figure from the feedback layer.
      Parameters:
      figure - the figure being removed
    • resetFlags

      protected void resetFlags()
      Resets all stateful flags to their initial values. Subclasses should extend this method to reset their own custom flags.
    • setCurrentCommand

      protected void setCurrentCommand(Command c)
      Used to cache a command obtained from getCommand().
      Parameters:
      c - the command
      See Also:
    • setCursor

      protected void setCursor(Cursor cursor)
      Shows the given cursor on the current viewer.
      Parameters:
      cursor - the cursor to display
    • setDefaultCursor

      public void setDefaultCursor(Cursor cursor)
      Sets the default cursor.
      Parameters:
      cursor - the cursor
      See Also:
    • setDisabledCursor

      public void setDisabledCursor(Cursor cursor)
      Sets the disabled cursor.
      Parameters:
      cursor - the cursor
      See Also:
    • setEditDomain

      public void setEditDomain(EditDomain domain)
      Sets the EditDomain.
      Specified by:
      setEditDomain in interface Tool
      Parameters:
      domain - the edit domain
      See Also:
    • setHoverActive

      protected void setHoverActive(boolean value)
      Sets whether the hover flag is true or false. Subclasses which do something on hover can use this flag to track whether they have received a hover or not.
      Parameters:
      value - whether hover is active
    • setProperties

      public void setProperties(Map properties)
      An example is PROPERTY_UNLOAD_WHEN_FINISHED -> Boolean. AbstractTool uses introspection to set properties that are not explicitly specified. For instance, the key "defaultCursor" will cause setDefaultCursor(Cursor) to be invoked with the given value.
      Specified by:
      setProperties in interface Tool
      Parameters:
      properties - a mapping of the properties to be set and their new values; can be null
      See Also:
    • setStartLocation

      protected void setStartLocation(org.eclipse.draw2d.geometry.Point p)
      Sets the start mouse location, typically for a drag operation.
      Parameters:
      p - the start location
    • setState

      protected void setState(int state)
      Sets the tools state.
      Parameters:
      state - the new state
    • setToolCapture

      protected void setToolCapture()
      Sets tool capture. When a tool has capture, viewers will make every effort to send events through the editdomain to the tool. Therefore, the default handling of some events is bypassed.
    • setUnloadWhenFinished

      public void setUnloadWhenFinished(boolean value)
      Setting this to true will cause the tool to be unloaded after one operation has completed. The default value is true . The tool is unloaded, and the edit domains default tool will be activated.
      Parameters:
      value - whether the tool should be unloaded on completion
    • setViewer

      public void setViewer(EditPartViewer viewer)
      Sets the active EditPartViewer. The active viewer is the viewer from which the last event was received.
      Specified by:
      setViewer in interface Tool
      Parameters:
      viewer - the viewer
    • stateTransition

      protected boolean stateTransition(int start, int end)
      Returns true if the give state transition succeeds. This is a "test and set" operation, where the tool is tested to be in the specified start state, and if so, is set to the given end state. The method returns the result of the first test.
      Parameters:
      start - the start state being tested
      end - the end state
      Returns:
      true if the state transition is successful
    • unloadWhenFinished

      protected final boolean unloadWhenFinished()
      Returns true if the tool is set to unload when its current operation is complete.
      Returns:
      true if the tool should be unloaded when finished
    • viewerEntered

      public void viewerEntered(MouseEvent me, EditPartViewer viewer)
      Receives the mouse entered event. Subclasses wanting to handle this event should override handleViewerEntered().

      FEATURE in SWT: mouseExit comes after mouseEntered on the new control. Therefore, if the current viewer is not null, it means the exit has not been sent yet by SWT. To maintain proper ordering, GEF fakes the exit and calls handleViewerExited(). The real exit will then be ignored.

      Specified by:
      viewerEntered in interface Tool
      Parameters:
      me - the mouse event
      viewer - the originating viewer
    • viewerExited

      public void viewerExited(MouseEvent me, EditPartViewer viewer)
      Handles the mouse exited event. Subclasses wanting to handle this event should override handleViewerExited().
      Specified by:
      viewerExited in interface Tool
      Parameters:
      me - the mouse event
      viewer - the originating viewer