Package org.opencms.gwt.client.dnd

Class CmsDNDHandler

java.lang.Object

org.opencms.gwt.client.dnd.CmsDNDHandler

All Implemented Interfaces:

com.google.gwt.event.dom.client.MouseDownHandler, com.google.gwt.event.shared.EventHandler

public class CmsDNDHandler
extends java.lang.Object
implements com.google.gwt.event.dom.client.MouseDownHandler

Drag and drop handler.

Since:

8.0.0

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	CmsDNDHandler.AnimationType	The animation types.
protected class	CmsDNDHandler.CmsScrollTimer	Timer to schedule automated scrolling.
protected static class	CmsDNDHandler.Direction	Scroll direction enumeration.
protected class	CmsDNDHandler.DNDEventPreviewHandler	Drag and drop event preview handler.
static class	CmsDNDHandler.Orientation	The allowed drag and drop orientation.

Constructor Summary

Constructors

Constructor	Description
CmsDNDHandler(I_CmsDNDController controller)	Constructor.

Method Summary

Modifier and Type	Method	Description
void	addTarget(I_CmsDropTarget target)	Adds a drop target.
protected void	animateCancel(I_CmsDraggable draggable, I_CmsDNDController controller)	Clears the drag process with a move animation of the drag element to it's original position.
protected void	animateDrop(I_CmsDraggable draggable, I_CmsDropTarget target, I_CmsDNDController controller)	Clears the drag process with a move animation of the drag element to the place-holder position.
void	cancel()	Cancels the dragging process.
protected void	clear()	Clears all references used within the current drag process.
protected void	clearScrollTimer()	Cancels the scroll timer and removes the timer reference.
void	clearTargets()	Clears the drop target register.
void	drop()	Drops the draggable.
I_CmsDNDController	getController()	Returns the drag and drop controller.
I_CmsDropTarget	getCurrentTarget()	Returns the current drop target.
int	getCursorOffsetX()	Returns the cursor offset x.
int	getCursorOffsetY()	Returns the cursor offset y.
I_CmsDraggable	getDraggable()	Returns the current draggable.
com.google.gwt.dom.client.Element	getDragHelper()	Returns the drag helper element.
CmsDNDHandler.Orientation	getOrientation()	Returns the allowed drag and drop orientation.
com.google.gwt.dom.client.Element	getPlaceholder()	Returns the place holder element.
boolean	hasModifierCTRL()	Returns whether the CTRL key was pressed when drag started.
boolean	isAnimationEnabled()	Returns if the animation is enabled.
boolean	isDragging()	Returns if a dragging process is taking place.
boolean	isScrollEnabled()	Returns if automated scrolling is enabled.
void	onMouseDown(com.google.gwt.event.dom.client.MouseDownEvent event)
protected void	onMouseWheelScroll(com.google.gwt.user.client.Event event)	Execute on mouse wheel event.
protected void	onMove(com.google.gwt.user.client.Event event)	Executed on mouse move while dragging.
protected void	onUp(com.google.gwt.user.client.Event event)	Executed on mouse up while dragging.
protected void	positionHelper()	Positions an element depending on the current events client position and the cursor offset.
void	removeTarget(I_CmsDropTarget target)	Removes a drop target from the register.
void	setAnimationType(CmsDNDHandler.AnimationType animationType)	Sets the animation type.
void	setController(I_CmsDNDController controller)	Sets the drag and drop controller.
void	setCursorOffsetX(int cursorOffsetX)	Sets the cursor offset x.
void	setCursorOffsetY(int cursorOffsetY)	Sets the cursor offset y.
void	setDraggable(I_CmsDraggable draggable)	Sets the draggable.
void	setDragHelper(com.google.gwt.dom.client.Element dragHelper)	Sets the drag helper element.
void	setOrientation(CmsDNDHandler.Orientation orientation)	Sets the allowed drag and drop orientation.
void	setPlaceholder(com.google.gwt.dom.client.Element placeholder)	Sets the placeholder element.
void	setScrollElement(com.google.gwt.dom.client.Element scrollElement)	Sets the scroll element in case not the window but another element needs scrolling.
void	setScrollEnabled(boolean scrollEnabled)	Sets the scrolling enabled.
void	setStartPosition(int left, int top)	Sets the start position.
protected void	stopDragging()	Sets dragging to false and removes the event preview handler.
void	updatePosition()	Updates the position of the helper within the the appropriate target.

Methods inherited from class java.lang.Object

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

Constructor Detail

CmsDNDHandler

public CmsDNDHandler(I_CmsDNDController controller)

Constructor.

Parameters:

controller - the drag and drop controller

Method Detail

addTarget

public void addTarget(I_CmsDropTarget target)

Adds a drop target.

Parameters:

target - the target to add

cancel

public void cancel()

Cancels the dragging process.

clearTargets

public void clearTargets()

Clears the drop target register.

drop

public void drop()

Drops the draggable.

getController

public I_CmsDNDController getController()

Returns the drag and drop controller.

Returns:

the drag and drop controller

getCurrentTarget

public I_CmsDropTarget getCurrentTarget()

Returns the current drop target.

Returns:

the current drop target

getCursorOffsetX

public int getCursorOffsetX()

Returns the cursor offset x.

Returns:

the cursor offset x

getCursorOffsetY

public int getCursorOffsetY()

Returns the cursor offset y.

Returns:

the cursor offset y

getDraggable

public I_CmsDraggable getDraggable()

Returns the current draggable.

Returns:

the draggable

getDragHelper

public com.google.gwt.dom.client.Element getDragHelper()

Returns the drag helper element.

Returns:

the drag helper

getOrientation

public CmsDNDHandler.Orientation getOrientation()

Returns the allowed drag and drop orientation.

Returns:

the drag and drop orientation

getPlaceholder

public com.google.gwt.dom.client.Element getPlaceholder()

Returns the place holder element.

Returns:

the place holder element

hasModifierCTRL

public boolean hasModifierCTRL()

Returns whether the CTRL key was pressed when drag started.

Returns:

true if CTRL key was pressed when drag started

isAnimationEnabled

public boolean isAnimationEnabled()

Returns if the animation is enabled.

Returns:

true if the animation is enabled

isDragging

public boolean isDragging()

Returns if a dragging process is taking place.

Returns:

true if the handler is currently dragging

isScrollEnabled

public boolean isScrollEnabled()

Returns if automated scrolling is enabled.

Returns:

if automated scrolling is enabled

onMouseDown

public void onMouseDown(com.google.gwt.event.dom.client.MouseDownEvent event)

Specified by:

onMouseDown in interface com.google.gwt.event.dom.client.MouseDownHandler

See Also:

MouseDownHandler.onMouseDown(com.google.gwt.event.dom.client.MouseDownEvent)

removeTarget

public void removeTarget(I_CmsDropTarget target)

Removes a drop target from the register.

Parameters:

target - the target to remove

setAnimationType

public void setAnimationType(CmsDNDHandler.AnimationType animationType)

Sets the animation type.

Parameters:

animationType - the animation type

setController

public void setController(I_CmsDNDController controller)

Sets the drag and drop controller.

Parameters:

controller - the drag and drop controller to set

setCursorOffsetX

public void setCursorOffsetX(int cursorOffsetX)

Sets the cursor offset x.

Parameters:

cursorOffsetX - the cursor offset x to set

setCursorOffsetY

public void setCursorOffsetY(int cursorOffsetY)

Sets the cursor offset y.

Parameters:

cursorOffsetY - the cursor offset y to set

setDraggable

public void setDraggable(I_CmsDraggable draggable)

Sets the draggable.

Parameters:

draggable - the draggable

setDragHelper

public void setDragHelper(com.google.gwt.dom.client.Element dragHelper)

Sets the drag helper element.

Parameters:

dragHelper - the drag helper element

setOrientation

public void setOrientation(CmsDNDHandler.Orientation orientation)

Sets the allowed drag and drop orientation.

Parameters:

orientation - the drag and drop orientation to set

setPlaceholder

public void setPlaceholder(com.google.gwt.dom.client.Element placeholder)

Sets the placeholder element.

Parameters:

placeholder - the placeholder element

setScrollElement

public void setScrollElement(com.google.gwt.dom.client.Element scrollElement)

Sets the scroll element in case not the window but another element needs scrolling.

Parameters:

scrollElement - the scroll element

setScrollEnabled

public void setScrollEnabled(boolean scrollEnabled)

Sets the scrolling enabled.

Parameters:

scrollEnabled - true to enable scrolling

setStartPosition

public void setStartPosition(int left,
                             int top)

Sets the start position.

In case of a canceled drag and drop and enabled animation, the draggable helper element will be reverted to the start position.

Values <0 will be ignored.

Parameters:

left - the left position

top - the top position

updatePosition

public void updatePosition()

Updates the position of the helper within the the appropriate target.

Needs to be executed on mouse move or when the list of allowed targets changes.

Uses the currently stored cursor position.

animateCancel

protected void animateCancel(I_CmsDraggable draggable,
                             I_CmsDNDController controller)

Clears the drag process with a move animation of the drag element to it's original position.

Parameters:

draggable - the draggable

controller - the drag and drop controller

animateDrop

protected void animateDrop(I_CmsDraggable draggable,
                           I_CmsDropTarget target,
                           I_CmsDNDController controller)

Clears the drag process with a move animation of the drag element to the place-holder position.

Parameters:

draggable - the draggable

target - the drop target

controller - the drag and drop controller

clear

protected void clear()

Clears all references used within the current drag process.

clearScrollTimer

protected void clearScrollTimer()

Cancels the scroll timer and removes the timer reference.

onMouseWheelScroll

protected void onMouseWheelScroll(com.google.gwt.user.client.Event event)

Execute on mouse wheel event.

Parameters:

event - the native event

onMove

protected void onMove(com.google.gwt.user.client.Event event)

Executed on mouse move while dragging.

Parameters:

event - the event

onUp

protected void onUp(com.google.gwt.user.client.Event event)

Executed on mouse up while dragging.

Parameters:

event - the event

positionHelper

protected void positionHelper()

Positions an element depending on the current events client position and the cursor offset. This method assumes that the element parent is positioned relative.

stopDragging

protected void stopDragging()

Sets dragging to false and removes the event preview handler.