org.eclipse.gef.tools
Class SimpleDragTracker

java.lang.Object
  org.eclipse.gef.util.FlagSupport
      org.eclipse.gef.tools.AbstractTool
          org.eclipse.gef.tools.SimpleDragTracker

All Implemented Interfaces:

DragTracker, RequestConstants, Tool

Direct Known Subclasses:

ConnectionBendpointTracker, ResizeTracker

public abstract class SimpleDragTracker
extends AbstractTool
implements DragTracker

A simple drag tracker implementation that does not perform targeting. For example, resizing a shape or bendpoint does not involve any target editpart.

Nested Class Summary

Nested classes/interfaces inherited from class org.eclipse.gef.tools.AbstractTool

AbstractTool.Input

Field Summary

protected static int

MAX_FLAG The maximum bit-mask used as a flag constant.

Fields inherited from class org.eclipse.gef.tools.AbstractTool

MAX_STATE, MOUSE_BUTTON_ANY, MOUSE_BUTTON1, MOUSE_BUTTON2, MOUSE_BUTTON3, PROPERTY_UNLOAD_WHEN_FINISHED, STATE_ACCESSIBLE_DRAG, STATE_ACCESSIBLE_DRAG_IN_PROGRESS, STATE_DRAG, STATE_DRAG_IN_PROGRESS, STATE_INITIAL, STATE_INVALID, STATE_TERMINAL

Fields inherited from interface org.eclipse.gef.RequestConstants

REQ_ADD, REQ_ALIGN, REQ_ALIGN_CHILDREN, REQ_CLONE, REQ_CONNECTION_END, REQ_CONNECTION_START, REQ_CREATE, REQ_CREATE_BENDPOINT, REQ_DELETE, REQ_DELETE_DEPENDANT, REQ_DIRECT_EDIT, REQ_MOVE, REQ_MOVE_BENDPOINT, REQ_MOVE_CHILDREN, REQ_OPEN, REQ_ORPHAN, REQ_ORPHAN_CHILDREN, REQ_RECONNECT_SOURCE, REQ_RECONNECT_TARGET, REQ_RESIZE, REQ_RESIZE_CHILDREN, REQ_SELECTION, REQ_SELECTION_HOVER

Constructor Summary

protected

SimpleDragTracker() Null constructor.

Method Summary

protected Cursor	calculateCursor() Returns the appropriate cursor for the tools current state.
void	commitDrag() Added for compatibility.
protected Request	createSourceRequest() Creates and returns a new Request that is used during the drag.
void	deactivate() Deactivates the tool.
protected void	eraseSourceFeedback() Show the source drag feedback for the drag occurring within the viewer.
protected Request	getSourceRequest() Returns the request for the source of the drag, creating it if necessary.
protected boolean	handleButtonDown(int button) Looks for button 1, and goes into the drag state.
protected boolean	handleButtonUp(int button) If dragging is in progress, cleans up feedback and calls performDrag().
protected boolean	handleDragInProgress() Called whenever a mouse is being dragged and the drag threshold has been exceeded.
protected boolean	handleDragStarted() Transitions Drag to Drag in progress state.
protected boolean	handleInvalidInput() Called when the mouse and/or keyboard input is invalid.
protected boolean	handleKeyDown(KeyEvent e) Looks for keys which are used during accessible drags.
protected boolean	handleKeyUp(KeyEvent e) Handles high-level processing of a key up event.
protected boolean	isShowingFeedback() Returns true if feedback is being shown.
protected void	performDrag() Called once the drag has been interpreted.
protected void	showSourceFeedback() Show the source drag feedback for the drag occurring within the viewer.
protected void	updateSourceRequest() Updates the source request.

Methods inherited from class org.eclipse.gef.tools.AbstractTool

acceptArrowKey, activate, addFeedback, applyProperty, createOperationSet, debug, executeCommand, executeCurrentCommand, focusGained, focusLost, getCommand, getCommandName, getCurrentCommand, getCurrentInput, getCurrentViewer, getDebugName, getDebugNameForState, getDefaultCursor, getDisabledCursor, getDomain, getDragMoveDelta, getLocation, getOperationSet, getStartLocation, getState, handleCommandStackChanged, handleDoubleClick, handleDrag, handleFinished, handleFocusGained, handleFocusLost, handleHover, handleKeyTraversed, handleMove, handleNativeDragFinished, handleNativeDragStarted, handleViewerEntered, handleViewerExited, isActive, isHoverActive, isInState, isViewerImportant, keyDown, keyTraversed, keyUp, mouseDoubleClick, mouseDown, mouseDrag, mouseHover, mouseMove, mouseUp, mouseWheelScrolled, movedPastThreshold, nativeDragFinished, nativeDragStarted, performViewerMouseWheel, placeMouseInViewer, reactivate, refreshCursor, releaseToolCapture, removeFeedback, resetFlags, setCurrentCommand, setCursor, setDefaultCursor, setDisabledCursor, setEditDomain, setHoverActive, setProperties, setStartLocation, setState, setToolCapture, setUnloadWhenFinished, setViewer, stateTransition, unloadWhenFinished, viewerEntered, viewerExited

Methods inherited from class org.eclipse.gef.util.FlagSupport

getFlag, setFlag

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.eclipse.gef.Tool

activate, focusGained, focusLost, keyDown, keyTraversed, keyUp, mouseDoubleClick, mouseDown, mouseDrag, mouseHover, mouseMove, mouseUp, mouseWheelScrolled, nativeDragFinished, nativeDragStarted, setEditDomain, setProperties, setViewer, viewerEntered, viewerExited

Field Detail

MAX_FLAG

protected static final int MAX_FLAG

The maximum bit-mask used as a flag constant. Subclasses should start using the next highest bitmask.

See Also:

Constant Field Values

Constructor Detail

SimpleDragTracker

protected SimpleDragTracker()

Null constructor.

Method Detail

calculateCursor

protected Cursor calculateCursor()

Description copied from class: AbstractTool

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.

Overrides:

calculateCursor in class AbstractTool

Returns:

null or a cursor to be displayed.

See Also:

AbstractTool.calculateCursor()

commitDrag

public void commitDrag()

Description copied from class: AbstractTool

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.

Specified by:

commitDrag in interface DragTracker

Overrides:

commitDrag in class AbstractTool

See Also:

DragTracker.commitDrag()

createSourceRequest

protected Request createSourceRequest()

Creates and returns a new Request that is used during the drag.

Returns:

a new source request

deactivate

public void deactivate()

Description copied from class: AbstractTool

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

Overrides:

deactivate in class AbstractTool

See Also:

Tool.deactivate()

eraseSourceFeedback

protected void eraseSourceFeedback()

Show the source drag feedback for the drag occurring within the viewer.

getSourceRequest

protected Request getSourceRequest()

Returns the request for the source of the drag, creating it if necessary.

Returns:

the source request

handleButtonDown

protected boolean handleButtonDown(int button)

Looks for button 1, and goes into the drag state. Any other button is invalid input.

Overrides:

handleButtonDown in class AbstractTool

Parameters:

button - which button went down

Returns:

true if the buttonDown was handled

See Also:

AbstractTool.handleButtonDown(int)

handleButtonUp

protected boolean handleButtonUp(int button)

If dragging is in progress, cleans up feedback and calls performDrag().

Overrides:

handleButtonUp in class AbstractTool

Parameters:

button - the button being released

Returns:

true if the button up was handled

See Also:

AbstractTool.handleButtonUp(int)

handleDragInProgress

protected boolean handleDragInProgress()

Description copied from class: AbstractTool

Called whenever a mouse is being dragged and the drag threshold has been exceeded. Prior to the drag threshold being exceeded, only AbstractTool.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.

Overrides:

handleDragInProgress in class AbstractTool

Returns:

true if the drag was handled

See Also:

AbstractTool.handleDragInProgress()

handleDragStarted

protected boolean handleDragStarted()

Transitions Drag to Drag in progress state.

Overrides:

handleDragStarted in class AbstractTool

Returns:

true if the drag starting was handled

See Also:

AbstractTool.handleDragStarted()

handleInvalidInput

protected boolean handleInvalidInput()

Called when the mouse and/or keyboard input is invalid.

Overrides:

handleInvalidInput in class AbstractTool

Returns:

true

handleKeyDown

protected boolean handleKeyDown(KeyEvent e)

Looks for keys which are used during accessible drags.

Overrides:

handleKeyDown in class AbstractTool

Parameters:

e - the key event

Returns:

true if the key down was handled.

See Also:

AbstractTool.handleKeyDown(org.eclipse.swt.events.KeyEvent)

handleKeyUp

protected boolean handleKeyUp(KeyEvent e)

Description copied from class: AbstractTool

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.

Overrides:

handleKeyUp in class AbstractTool

Parameters:

e - the key event

Returns:

true if the event was handled

See Also:

AbstractTool.handleKeyUp(org.eclipse.swt.events.KeyEvent)

isShowingFeedback

protected boolean isShowingFeedback()

Returns true if feedback is being shown.

Returns:

true if feedback is showing

performDrag

protected void performDrag()

Called once the drag has been interpreted. This is where the real work of the drag is carried out. By default, the current command is executed.

showSourceFeedback

protected void showSourceFeedback()

Show the source drag feedback for the drag occurring within the viewer.

updateSourceRequest

protected void updateSourceRequest()

Updates the source request.