edu.umd.cs.jazz.event
Class ZSelectionModifyHandler

java.lang.Object
  |
  +--edu.umd.cs.jazz.event.ZFilteredEventHandler
        |
        +--edu.umd.cs.jazz.event.ZDragSequenceEventHandler
              |
              +--edu.umd.cs.jazz.event.ZSelectionModifyHandler

All Implemented Interfaces:

ZEventHandler

public class ZSelectionModifyHandler

extends ZDragSequenceEventHandler

ZSelectionModifyHandler is a ZEventHandler that allows items to be selected with the mouse, and maintains the current selection. As an event handler, ZSelectionManager directly supports the following actions:

• Click to select/unselect an item.
• Click-and-drag on the background to marquee select.

Author:

Antony Courtney, Yale University

, Lance Good, University of Maryland , Benjamin Bederson, University of Maryland , Jesse Grosjean, University of Maryland

See Also:

ZSelectionManager, ZCompositeSelectionHandler, ZSelectionDeleteHandler, ZSelectionMoveHandler, ZSelectionScaleHandler

ZSelectionModifyHandler

public ZSelectionModifyHandler(ZSceneGraphObject aFilteredMouseEventSource,
                               ZGroup aMarqueeLayer)

Construct a new ZSelectionModifyHandler.

Parameters:

aFilteredMouseEventSource - the source for filtered ZMouseEvents and ZMouseMotionEvents. See the class comment to customize this behavior.

ZSelectionModifyHandler

public ZSelectionModifyHandler(ZSceneGraphObject aFilteredMouseEventSource,
                               ZCanvas aIgnoredCanvas,
                               ZGroup aMarqueeLayer)

Deprecated. As of Jazz version 1.2, use ZSelectionModifyHandler(ZSceneGraphObject aFilteredMouseEventSource, ZGroup aMarqueeLayer) instead.

getMouseFilter

public ZMouseFilter getMouseFilter()

Modifying the selection works with BUTTON1 by default.

Overrides:

getMouseFilter in class ZFilteredEventHandler

Returns:

the filter that is currently in effect.

filteredMousePressed

protected void filteredMousePressed(ZMouseEvent e)

On mouse pressed try to select the node under the cursor.

Overrides:

filteredMousePressed in class ZDragSequenceEventHandler

Parameters:

e - the filtered mouse pressed event.

startDrag

protected void startDrag(ZMouseEvent e)

Forward the message to startMarqueeSelection if shouldStartMarqueeSelection returns true. Otherwise make the mouse filter reject all events until the next mouse pressed that it sees.

Overrides:

startDrag in class ZDragSequenceEventHandler

Parameters:

e - the event starting the drag sequence.

dragInScreenCoords

protected void dragInScreenCoords(ZMouseEvent e,
                                  java.awt.geom.Dimension2D aScreenDelta)

Forward the message to modifyMarqueeSelection.

Overrides:

dragInScreenCoords in class ZDragSequenceEventHandler

Parameters:

e - the event causing the drag.

aScreenDelta - the change in mouse position between the current and last filtered mouse events.

endDrag

protected void endDrag(ZMouseEvent e)

Forward the message to endMarqueeSelection.

Overrides:

endDrag in class ZDragSequenceEventHandler

Parameters:

e - the event causing the end of the drag sequence.

makeSelection

protected void makeSelection(ZNode aNode,
                             ZMouseEvent e)

Select aNode. If the event isOptionSelection then option select the node, otherwise unselect all nodes and then select aNode.

getNodeToSelect

protected ZNode getNodeToSelect(ZMouseEvent e)

Return the node that should be selected for the given event, null if no node should be selected.

unselectAll

protected void unselectAll()

Unselect all selected nodes seen from the current interaction camera.

startMarqueeSelection

protected void startMarqueeSelection(ZMouseEvent e)

Start a new marquee selection. This creates a new marquee visual component and adds it to the marquee layer.

modifyMarqueeSelection

protected void modifyMarqueeSelection(ZMouseEvent e,
                                      java.awt.geom.Dimension2D aScreenDelta)

Modify the current marquee selection by aScreenDelta. This will update the current nodes that are selected and the current shape of the marquee.

endMarqueeSelection

protected void endMarqueeSelection(ZMouseEvent e)

Remove the marquee visual leaf and set the last marquee selection to null.

shouldStartMarqueeSelection

protected boolean shouldStartMarqueeSelection(ZMouseEvent e)

Return true if no node is currently under the cursor that should be selected.

getResizedMarqueeBounds

protected ZBounds getResizedMarqueeBounds(ZMouseEvent e,
                                          java.awt.geom.Dimension2D aScreenDelta)

Resize the marquee by aScreenDelta and return the resulting bounds.

getNewMarqueeSelection

protected java.util.Collection getNewMarqueeSelection(ZBounds aBounds)

Return the collection of nodes that intersect aBounds from the interaction cameras perspective.

getLastMarqueeSelection

protected java.util.Collection getLastMarqueeSelection()

Get the collection of nodes that were in the last marquee selection.

setLastMarqueeSelection

protected void setLastMarqueeSelection(java.util.Collection aCollection)

Set the collection of nodes that were in the last marquee selection.

getMarqueeLayer

public ZGroup getMarqueeLayer()

Get the layer that the marquee upon which the marquee should be drawn.

setMarqueeLayer

public void setMarqueeLayer(ZGroup aGroup)

Set the layer tha the marquee upon which the marquee should be drawn.

getMarqueeLeaf

public ZVisualLeaf getMarqueeLeaf()

Return the leaf from which the marquee visual component should hang.

setMarqueeLeaf

public void setMarqueeLeaf(ZVisualLeaf aMarquee)

Set the leaf from which the marquee visual component should hang.

getMarqueeVisualComponent

public ZVisualComponent getMarqueeVisualComponent()

Return the visual component used to draw the marquee.

setMarqueeVisualComponent

public void setMarqueeVisualComponent(ZVisualComponent aMarquee)

Set the visual component used to draw the marquee.

setMarqueeBounds

public void setMarqueeBounds(ZBounds aBounds)

Set the bounds of the marquee visual component to the new bounds.

isOptionSelection

protected boolean isOptionSelection(ZMouseEvent e)

Return true if the event is an option selection. Option selection events select unselected nodes, and deselect selected nodes.

setActive

public void setActive(boolean active)

Specifies whether this event handler is active or not. An active event handler is registered with its event sources for events. An inactive event handler is not registered with its event sources and so will not receive events.

Specified by:

setActive in interface ZEventHandler

Overrides:

setActive in class ZFilteredEventHandler

Parameters:

active - true to make this event handler active.