org.openquark.gems.client.utilities
Class MouseClickDragListener

java.lang.Object
  org.openquark.gems.client.utilities.MouseClickDragListener

All Implemented Interfaces:

MouseListener, MouseMotionListener, EventListener

Direct Known Subclasses:

MouseClickDragAdapter

public abstract class MouseClickDragListener
extends Object
implements MouseListener, MouseMotionListener

MouseListener and MouseMotionListener that use reasonable models for click and drag Creation date: (12/13/01 4:28:24 PM)

Author:

Edward Lam

Nested Class Summary

static class

MouseClickDragListener.DragMode Drag action enum pattern.

Field Summary

protected static int	DOUBLE_CLICK_OFFSET_LIMIT Max distance between clicks to count as a double click
protected static long	DOUBLE_CLICK_THRESHOLD_TIME The number of milliseconds that should bound a double click.
protected boolean	dragInitiatedWithCTRL The current drag was initiated with the CTRL modifier.
protected boolean	dragInitiatedWithSHIFT The current drag was initiated with the SHIFT modifier.
protected MouseClickDragListener.DragMode	dragMode What type of dragging action we are performing.
protected static int	INITIAL_DRAG_OFFSET Naggle size the mouse can move before a button press becomes a drag
protected Point	pressedAt Where we pressed.

Constructor Summary

MouseClickDragListener()
Constructor for a MouseClickDragListener Creation date: (12/13/01 4:41:24 PM)

Method Summary

protected void	abortDrag() Move the drag mode into the aborted state.
void	enterDragState(MouseEvent e) Carry out setup appropriate to enter the drag state.
void	exitDragState(MouseEvent e) Carry out setup appropriate to exit the drag state.
static int	getNumMouseButtons(MouseEvent e) Return the number of mouse buttons associated with a mouse event.
protected boolean	isUsefulDragMode(MouseClickDragListener.DragMode mode) Whether this drag mode actually enables accomplishing anything.
void	mouseClicked(MouseEvent e) Invoked when the mouse has been clicked on a component.
void	mouseDragged(MouseEvent e) Creation date: (12/13/01 4:28:24 PM)
void	mousePressed(MouseEvent e) Invoked when a mouse button has been pressed on a component.
boolean	mouseReallyClicked(MouseEvent e) Surrogate method for mouseClicked.
abstract void	mouseReallyDragged(MouseEvent e, Point where, boolean wasDragging) Surrogate method for mouseDragged.
void	mouseReleased(MouseEvent e) Invoked when a mouse button has been released on a component.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.awt.event.MouseListener

mouseEntered, mouseExited

Methods inherited from interface java.awt.event.MouseMotionListener

mouseMoved

Field Detail

INITIAL_DRAG_OFFSET

protected static final int INITIAL_DRAG_OFFSET

Naggle size the mouse can move before a button press becomes a drag

See Also:

Constant Field Values

DOUBLE_CLICK_OFFSET_LIMIT

protected static final int DOUBLE_CLICK_OFFSET_LIMIT

Max distance between clicks to count as a double click

See Also:

Constant Field Values

DOUBLE_CLICK_THRESHOLD_TIME

protected static final long DOUBLE_CLICK_THRESHOLD_TIME

The number of milliseconds that should bound a double click.

See Also:

Constant Field Values

pressedAt

protected Point pressedAt

Where we pressed. Null if we're not in the pressed state.

dragMode

protected MouseClickDragListener.DragMode dragMode

What type of dragging action we are performing.

dragInitiatedWithCTRL

protected boolean dragInitiatedWithCTRL

The current drag was initiated with the CTRL modifier. This allows us to tell when a drag was started with the CTRL modifier but didn't end with it.

dragInitiatedWithSHIFT

protected boolean dragInitiatedWithSHIFT

The current drag was initiated with the SHIFT modifier. This allows us to tell when a drag was started with the SHIFT modifier but didn't end with it.

Constructor Detail

MouseClickDragListener

public MouseClickDragListener()

Constructor for a MouseClickDragListener Creation date: (12/13/01 4:41:24 PM)

Method Detail

abortDrag

protected void abortDrag()

Move the drag mode into the aborted state. Creation date: (12/06/01 12:22:15 PM)

getNumMouseButtons

public static final int getNumMouseButtons(MouseEvent e)

Return the number of mouse buttons associated with a mouse event. Creation date: (03/08/2001 10:32:13 AM)

Parameters:

e - MouseEvent the mouse event

Returns:

int the number of buttons

isUsefulDragMode

protected boolean isUsefulDragMode(MouseClickDragListener.DragMode mode)

Whether this drag mode actually enables accomplishing anything. Gem dragging, connecting, disconnecting, and selecting are useful. Aborted, useless, and not-dragging states are not useful. Creation date: (12/06/01 3:31:30 PM)

Parameters:

mode - DragMode the DragMode to check

Returns:

boolean true if accomplishing anything with this drag.

mouseClicked

public final void mouseClicked(MouseEvent e)

Invoked when the mouse has been clicked on a component. Note: DO NOT USE unless you really want annoying UI behaviour. Use mouseReallyClicked() instead. You don't want to use this method (unless you're a masochist!) Mouse clicked events are not generated unless the pointer doesn't move even one pixel between press and release! Creation date: (12/13/01 4:28:24 PM)

Specified by:

mouseClicked in interface MouseListener

See Also:

MouseListener.mouseClicked(MouseEvent)

mouseDragged

public void mouseDragged(MouseEvent e)

Creation date: (12/13/01 4:28:24 PM)

Specified by:

mouseDragged in interface MouseMotionListener

See Also:

MouseMotionListener.mouseDragged(MouseEvent)

mousePressed

public void mousePressed(MouseEvent e)

Invoked when a mouse button has been pressed on a component. Creation date: (12/13/01 4:28:24 PM)

Specified by:

mousePressed in interface MouseListener

See Also:

MouseListener.mousePressed(MouseEvent)

mouseReleased

public void mouseReleased(MouseEvent e)

Invoked when a mouse button has been released on a component. Creation date: (12/13/01 4:28:24 PM)

Specified by:

mouseReleased in interface MouseListener

See Also:

MouseListener.mouseReleased(MouseEvent)

mouseReallyClicked

public boolean mouseReallyClicked(MouseEvent e)

Surrogate method for mouseClicked. Called only when our definition of click occurs. Creation date: (12/13/01 5:23:24 PM)

Parameters:

e - MouseEvent the relevant event

Returns:

boolean true if the click was a double click

mouseReallyDragged

public abstract void mouseReallyDragged(MouseEvent e,
                                        Point where,
                                        boolean wasDragging)

Surrogate method for mouseDragged. Called only when our definition of drag occurs. Creation date: (12/13/01 5:23:24 PM)

Parameters:

e - MouseEvent the relevant event

where - java.awt.Point the (possibly adjusted from e) coordinates of the drag

wasDragging - boolean True: this is a continuation of a drag. False: first call upon transition from pressed to drag.

enterDragState

public void enterDragState(MouseEvent e)

Carry out setup appropriate to enter the drag state. Principal effect is to change dragMode as appropriate. Creation date: (12/13/01 5:23:24 PM)

Parameters:

e - MouseEvent the mouse event which triggered entry into the drag state.

exitDragState

public void exitDragState(MouseEvent e)

Carry out setup appropriate to exit the drag state. Principal effect is to change dragMode as appropriate. Creation date: (12/06/01 6:14:42 PM)

Parameters:

e - MouseEvent the mouse event which caused an exit from the drag state