com.vaadin.shared.ui.dd.VerticalDropLocation Java Examples

/**
 * Removes any applies drag and drop style applied by emphasis()
 */
protected void deEmphasis() {
    if (currentlyEmphasised != null) {
        // Universal over style
        UIObject.setStyleName(currentlyEmphasised.getElement(), OVER,
                false);
        UIObject.setStyleName(currentlyEmphasised.getElement(), OVER_SPACED,
                false);

        // Vertical styles
        UIObject.setStyleName(currentlyEmphasised.getElement(),
                OVER + "-"
                        + VerticalDropLocation.TOP.toString().toLowerCase(),
                false);
        UIObject.setStyleName(currentlyEmphasised.getElement(), OVER + "-"
                + VerticalDropLocation.MIDDLE.toString().toLowerCase(),
                false);
        UIObject.setStyleName(currentlyEmphasised.getElement(), OVER + "-"
                + VerticalDropLocation.BOTTOM.toString().toLowerCase(),
                false);

        currentlyEmphasised = null;
    }
}
 

/**
 * Removes any applies drag and drop style applied by emphasis()
 */
protected void deEmphasis() {
    if (currentlyEmphasised != null) {
        // Universal over style
        setStyleName(currentlyEmphasised, OVER, false);
        setStyleName(currentlyEmphasised, OVER_SPACED, false);

        // Vertical styles
        setStyleName(currentlyEmphasised,
                OVER + "-"
                        + VerticalDropLocation.TOP.toString().toLowerCase(),
                false);
        setStyleName(currentlyEmphasised, OVER + "-"
                + VerticalDropLocation.MIDDLE.toString().toLowerCase(),
                false);
        setStyleName(currentlyEmphasised, OVER + "-"
                + VerticalDropLocation.BOTTOM.toString().toLowerCase(),
                false);

        currentlyEmphasised = null;
    }
}
 

/**
 * Returns the drop location of a tab
 * 
 * @param tab
 *            The tab that was dragged
 * @param event
 *            The drag event
 * @return
 */
protected VerticalDropLocation getDropLocation(StackItem tab,
        VDragEvent event) {
    VerticalDropLocation location;
    if (tab.isOpen()) {
        location = VDragDropUtil.getVerticalDropLocation(tab.getElement(),
                Util.getTouchOrMouseClientY(event.getCurrentGwtEvent()),
                tabTopBottomDropRatio);
    } else {
        location = VDragDropUtil
                .getVerticalDropLocation(tab.getWidget(0).getElement(),
                        Util.getTouchOrMouseClientY(
                                event.getCurrentGwtEvent()),
                tabTopBottomDropRatio);
    }
    return location;
}
 

/**
 * Updates the drop details while dragging. This is needed to ensure client
 * side criterias can validate the drop location.
 * 
 * @param event
 *            The drag event
 */
protected void updateDragDetails(VDragEvent event) {
    if (event.getElementOver() == null) {
        return;
    }

    StackItem tab = WidgetUtil.findWidget(event.getElementOver(),
            StackItem.class);

    if (tab != null && getElement().isOrHasChild(tab.getElement())) {
        Map<String, Object> dropDetails = event.getDropDetails();

        int index = getTabPosition(tab);
        dropDetails.put(Constants.DROP_DETAIL_TO, index);

        VerticalDropLocation location = getDropLocation(tab, event);
        dropDetails.put(Constants.DROP_DETAIL_VERTICAL_DROP_LOCATION,
                location);

        MouseEventDetails details = MouseEventDetailsBuilder
                .buildMouseEventDetails(event.getCurrentGwtEvent(),
                        getElement());
        dropDetails.put(Constants.DROP_DETAIL_MOUSE_EVENT,
                details.serialize());
    }
}
 

/**
 * Removes any applies drag and drop style applied by emphasis()
 */
protected void deEmphasis() {
    if (currentlyEmphasised != null) {
        // Universal over style
        setStyleName(currentlyEmphasised.getElement(), OVER,
                false);
        setStyleName(currentlyEmphasised.getElement(), OVER_SPACED,
                false);

        // Vertical styles
        setStyleName(currentlyEmphasised.getElement(),
                OVER + "-"
                        + VerticalDropLocation.TOP.toString().toLowerCase(),
                false);
        setStyleName(currentlyEmphasised.getElement(), OVER + "-"
                + VerticalDropLocation.MIDDLE.toString().toLowerCase(),
                false);
        setStyleName(currentlyEmphasised.getElement(), OVER + "-"
                + VerticalDropLocation.BOTTOM.toString().toLowerCase(),
                false);

        currentlyEmphasised = null;
    }
}
 

/**
 * Get the vertical drop location in a ordered layout
 * 
 * @param element
 *            The target element or cell
 * @param offsetHeight
 *            The height of the cell
 * @param clientY
 *            The width of the cell
 * @param topBottomRatio
 *            The ratio of the cell
 * @return The location of the drop
 */
public static VerticalDropLocation getVerticalDropLocation(Element element,
        int offsetHeight, int clientY, double topBottomRatio) {

    int absoluteTop = element.getAbsoluteTop();
    int fromTop = clientY - absoluteTop;

    float percentageFromTop = (fromTop / (float) offsetHeight);
    if (percentageFromTop < topBottomRatio) {
        return VerticalDropLocation.TOP;
    } else if (percentageFromTop > 1 - topBottomRatio) {
        return VerticalDropLocation.BOTTOM;
    } else {
        return VerticalDropLocation.MIDDLE;
    }
}
 

@Override
protected void handleHTML5Drop(DragAndDropEvent event) {
    AccordionTargetDetails details = (AccordionTargetDetails) event
            .getTargetDetails();
    VerticalDropLocation location = details.getDropLocation();
    DDAccordion acc = (DDAccordion) details.getTarget();
    int idx = details.getOverIndex();

    Component c = resolveComponentFromHTML5Drop(event);
    c.setCaption(resolveCaptionFromHTML5Drop(event));

    if (location == VerticalDropLocation.TOP) {
        acc.addTab(c, idx);
    } else if (location == VerticalDropLocation.BOTTOM) {
        acc.addTab(c, idx + 1);
    } else {
        acc.addTab(c);
    }
}
 

/**
 * Returns the vertical drop location
 * 
 * @param cell
 *            The cell details
 * @param event
 *            The drag event
 * @return
 */
protected VerticalDropLocation getVerticalDropLocation(CellDetails cell,
        VDragEvent event) {

    // Get the vertical location
    VerticalDropLocation vdetail;
    int y = Util.getTouchOrMouseClientY(event.getCurrentGwtEvent())
            - getAbsoluteTop() - cell.y;

    assert(y >= 0 && y <= cell.height);

    if (y < cell.height * cellTopBottomDropRatio) {
        vdetail = VerticalDropLocation.TOP;
    } else if (y < cell.height * (1.0 - cellTopBottomDropRatio)) {
        vdetail = VerticalDropLocation.MIDDLE;
    } else {
        vdetail = VerticalDropLocation.BOTTOM;
    }
    return vdetail;
}
 

/**
 * Updates the drop details while dragging. This is needed to ensure client
 * side criterias can validate the drop location.
 * 
 * @param event
 *            The drag event
 */
protected void updateDragDetails(VDragEvent event) {
    Element over = event.getElementOver();

    // Resolve where the drop was made
    VerticalDropLocation location = null;
    Widget content = null;
    if (firstContainer.isOrHasChild(over)) {
        location = VerticalDropLocation.TOP;
        content = Util.findWidget(firstContainer, null);
    } else if (splitter.isOrHasChild(over)) {
        location = VerticalDropLocation.MIDDLE;
        content = this;
    } else if (secondContainer.isOrHasChild(over)) {
        location = VerticalDropLocation.BOTTOM;
        content = Util.findWidget(secondContainer, null);
    }

    event.getDropDetails().put(Constants.DROP_DETAIL_VERTICAL_DROP_LOCATION,
            location);

    if (content != null) {
        event.getDropDetails().put(Constants.DROP_DETAIL_OVER_CLASS,
                content.getClass().getName());
    } else {
        event.getDropDetails().put(Constants.DROP_DETAIL_OVER_CLASS,
                this.getClass().getName());
    }

    // Add mouse event details
    MouseEventDetails details = MouseEventDetailsBuilder
            .buildMouseEventDetails(event.getCurrentGwtEvent(),
                    getElement());
    event.getDropDetails().put(Constants.DROP_DETAIL_MOUSE_EVENT,
            details.serialize());
}
 

@Override
protected void handleHTML5Drop(DragAndDropEvent event) {
    VerticalLayoutTargetDetails details = (VerticalLayoutTargetDetails) event
            .getTargetDetails();
    AbstractOrderedLayout layout = (AbstractOrderedLayout) details
            .getTarget();
    int idx = (details).getOverIndex();

    // Increase index if component is dropped after or above a
    // previous
    // component
    VerticalDropLocation loc = (details).getDropLocation();
    if (loc == VerticalDropLocation.MIDDLE
            || loc == VerticalDropLocation.BOTTOM) {
        idx++;
    }

    Component comp = resolveComponentFromHTML5Drop(event);

    // Add component
    if (idx >= 0) {
        layout.addComponent(comp, idx);
    } else {
        layout.addComponent(comp);
    }

    // Add component alignment if given
    if (dropAlignment != null) {
        layout.setComponentAlignment(comp, dropAlignment);
    }

}
 

protected VerticalSplitPanelTargetDetails(
        Map<String, Object> rawDropData) {
    super(rawDropData, DDVerticalSplitPanel.this);

    if (getDropLocation() == VerticalDropLocation.TOP) {
        over = getFirstComponent();
    } else if (getDropLocation() == VerticalDropLocation.BOTTOM) {
        over = getSecondComponent();
    } else {
        over = DDVerticalSplitPanel.this;
    }
}
 

@Override
protected void handleHTML5Drop(DragAndDropEvent event) {
    CssLayoutTargetDetails details = (CssLayoutTargetDetails) event
            .getTargetDetails();
    Component over = details.getOverComponent();
    DDCssLayout layout = (DDCssLayout) details.getTarget();
    int idx = (details).getOverIndex();
    HorizontalDropLocation hl = details.getHorizontalDropLocation();
    VerticalDropLocation vl = details.getVerticalDropLocation();

    if (over == layout) {
        if (vl == VerticalDropLocation.TOP
                || hl == HorizontalDropLocation.LEFT) {
            idx = 0;
        } else if (vl == VerticalDropLocation.BOTTOM
                || hl == HorizontalDropLocation.RIGHT) {
            idx = -1;
        }
    } else {
        if (vl == VerticalDropLocation.BOTTOM
                || hl == HorizontalDropLocation.RIGHT) {
            idx++;
        }
    }

    if (idx >= 0 && idx < layout.getComponentCount()) {
        layout.addComponent(resolveComponentFromHTML5Drop(event), idx);
    } else {
        layout.addComponent(resolveComponentFromHTML5Drop(event));
    }
}
 

@Override
protected void handleHTML5Drop(DragAndDropEvent event) {
    VerticalLayoutTargetDetails details = (VerticalLayoutTargetDetails) event
            .getTargetDetails();
    AbstractOrderedLayout layout = (AbstractOrderedLayout) details
            .getTarget();
    int idx = (details).getOverIndex();

    // Increase index if component is dropped after or above a
    // previous
    // component
    VerticalDropLocation loc = (details).getDropLocation();
    if (loc == VerticalDropLocation.MIDDLE
            || loc == VerticalDropLocation.BOTTOM) {
        idx++;
    }

    Component comp = resolveComponentFromHTML5Drop(event);

    // Add component
    if (idx >= 0) {
        layout.addComponent(comp, idx);
    } else {
        layout.addComponent(comp);
    }

    // Add component alignment if given
    if (dropAlignment != null) {
        layout.setComponentAlignment(comp, dropAlignment);
    }

}
 

@Override
protected void handleHTML5Drop(DragAndDropEvent event) {
    FormLayoutTargetDetails details = (FormLayoutTargetDetails) event
            .getTargetDetails();
    int idx = details.getOverIndex();
    AbstractOrderedLayout layout = (AbstractOrderedLayout) details
            .getTarget();

    // Increase index if component is dropped after or above a
    // previous component
    VerticalDropLocation loc = details.getDropLocation();
    if (loc == VerticalDropLocation.MIDDLE
            || loc == VerticalDropLocation.BOTTOM) {
        idx++;
    }

    // Add component
    if (idx >= 0) {
        layout.addComponent(resolveComponentFromHTML5Drop(event), idx);
    } else {
        layout.addComponent(resolveComponentFromHTML5Drop(event));
    }

    // Add component alignment if given
    if (dropAlignment != null) {
        layout.setComponentAlignment(resolveComponentFromHTML5Drop(event),
                dropAlignment);
    }
}
 

/**
 * Empasises the drop location of the component when hovering over a
 * ĆhildComponentContainer. Passing null as the container removes any
 * previous emphasis.
 * 
 * @param widget
 *            The container which we are hovering over
 * @param event
 *            The drag event
 */
protected void emphasis(Widget widget, VDragEvent event) {

    // Remove emphasis from previous hovers
    deEmphasis();

    // Validate
    if (widget == null || !getElement().isOrHasChild(widget.getElement())) {
        return;
    }

    /*
     * Get row for widget
     */
    Element rowElement = getRowFromChildElement(widget.getElement(),
            VDDFormLayout.this.getElement());

    currentlyEmphasised = rowElement;

    if (rowElement != this.getElement()) {
        VerticalDropLocation vl = getVerticalDropLocation(rowElement,
                event);
        setStyleName(rowElement,
                OVER + "-" + vl.toString().toLowerCase(), true);
    } else {
        setStyleName(rowElement, OVER, true);
    }
}
 

@Override
protected void handleDropFromLayout(DragAndDropEvent event) {
    LayoutBoundTransferable transferable = (LayoutBoundTransferable) event
            .getTransferable();
    VerticalSplitPanelTargetDetails details = (VerticalSplitPanelTargetDetails) event
            .getTargetDetails();
    Component component = transferable.getComponent();
    DDVerticalSplitPanel panel = (DDVerticalSplitPanel) details.getTarget();
    ComponentContainer source = (ComponentContainer) transferable
            .getSourceComponent();

    // Detach from old source
    if (source instanceof ComponentContainer) {
        ((ComponentContainer) source).removeComponent(component);
    } else if (source instanceof SingleComponentContainer) {
        ((SingleComponentContainer) source).setContent(null);
    }

    if (details.getDropLocation() == VerticalDropLocation.TOP) {
        // Dropped in the left area
        panel.setFirstComponent(component);

    } else if (details.getDropLocation() == VerticalDropLocation.BOTTOM) {
        // Dropped in the right area
        panel.setSecondComponent(component);
    }
}
 

/**
 * Emphasisizes a container element
 * 
 * @param element
 */
protected void emphasis(Element element, VDragEvent event) {

    // Find the tab
    StackItem tab = WidgetUtil.findWidget(element, StackItem.class);
    if (tab != null && getElement().isOrHasChild(tab.getElement())
            && currentlyEmphasised != tab) {
        VerticalDropLocation location = getDropLocation(tab, event);

        if (location == VerticalDropLocation.MIDDLE) {
            if (tab.isOpen()) {
                tab.addStyleName(CLASSNAME_OVER);
            } else {
                tab.getWidget(0).addStyleName(CLASSNAME_OVER);
            }
        } else if (!spacer.isAttached()) {
            if (location == VerticalDropLocation.TOP) {
                insertSpacer(spacer, getElement(), getWidgetIndex(tab));
                tab.setHeight(
                        (tab.getOffsetHeight() - spacer.getOffsetHeight())
                                + "px");
            } else if (location == VerticalDropLocation.BOTTOM) {
                insertSpacer(spacer, getElement(), getWidgetIndex(tab) + 1);
                int newHeight = tab.getOffsetHeight()
                        - spacer.getOffsetHeight();
                if (getWidgetIndex(spacer) == getWidgetCount() - 1) {
                    newHeight -= spacer.getOffsetHeight();
                }
                if (newHeight >= 0) {
                    tab.setHeight(newHeight + "px");
                }
            }
        }
        currentlyEmphasised = tab;
    }
}
 

/**
 * Empasises the drop location of the component when hovering over a
 * ĆhildComponentContainer. Passing null as the container removes any
 * previous emphasis.
 * 
 * @param container
 *            The container which we are hovering over
 * @param event
 *            The drag event
 */
protected void emphasis(Widget container, VDragEvent event) {

    // Remove emphasis from previous hovers
    deEmphasis();

    // validate container
    if (container == null
            || !getElement().isOrHasChild(container.getElement())) {
        return;
    }

    currentlyEmphasised = container;

    VerticalDropLocation location = null;

    // Add drop location specific style
    if (currentlyEmphasised != this) {
        location = getVerticalDropLocation(currentlyEmphasised, event);

    } else {
        location = VerticalDropLocation.MIDDLE;
    }

    UIObject.setStyleName(currentlyEmphasised.getElement(), OVER, true);
    UIObject.setStyleName(currentlyEmphasised.getElement(),
            OVER + "-" + location.toString().toLowerCase(), true);
}
 

/**
 * Get the horizontal position of the dropped component within the
 * underlying cell.
 * 
 * @return The drop location
 */
public VerticalDropLocation getDropLocation() {
    if (getData("vdetail") != null) {
        return VerticalDropLocation.valueOf((String) getData("vdetail"));
    } else {
        return null;
    }
}
 

/**
 * Empasises the drop location of the component when hovering over a
 * ĆhildComponentContainer. Passing null as the container removes any
 * previous emphasis.
 * 
 * @param container
 *            The container which we are hovering over
 * @param event
 *            The drag event
 */
protected void emphasis(Widget container, VDragEvent event) {

    // Remove emphasis from previous hovers
    deEmphasis();

    // validate container
    if (container == null
            || !getElement().isOrHasChild(container.getElement())) {
        return;
    }

    currentlyEmphasised = container;

    VerticalDropLocation location = null;

    // Add drop location specific style
    if (currentlyEmphasised != this) {
        location = getVerticalDropLocation(currentlyEmphasised, event);

    } else {
        location = VerticalDropLocation.MIDDLE;
    }

    setStyleName(currentlyEmphasised.getElement(), OVER, true);
    setStyleName(currentlyEmphasised.getElement(),
            OVER + "-" + location.toString().toLowerCase(), true);
}
 

@Override
protected void handleHTML5Drop(DragAndDropEvent event) {
    VerticalSplitPanelTargetDetails details = (VerticalSplitPanelTargetDetails) event
            .getTargetDetails();
    DDVerticalSplitPanel panel = (DDVerticalSplitPanel) details.getTarget();

    if (details.getDropLocation() == VerticalDropLocation.TOP) {
        // Dropped in the left area
        panel.setFirstComponent(resolveComponentFromHTML5Drop(event));

    } else if (details.getDropLocation() == VerticalDropLocation.BOTTOM) {
        // Dropped in the right area
        panel.setSecondComponent(resolveComponentFromHTML5Drop(event));
    }
}
 

/**
 * Emphasizes a component container when user is hovering a dragged
 * component over the container.
 * 
 * @param cell
 *            The container
 * @param event
 */
protected void emphasis(CellDetails cell, VDragEvent event) {

    Style shadowStyle = dragShadow.getElement().getStyle();
    shadowStyle.setPosition(Position.ABSOLUTE);
    shadowStyle.setWidth(cell.width, Unit.PX);
    shadowStyle.setHeight(cell.height, Unit.PX);
    shadowStyle.setLeft(cell.x, Unit.PX);
    shadowStyle.setTop(cell.y, Unit.PX);

    // Remove any existing empasis
    deEmphasis();

    // Ensure we are not dragging ourself into ourself
    ComponentConnector draggedConnector = (ComponentConnector) event
            .getTransferable()
            .getData(Constants.TRANSFERABLE_DETAIL_COMPONENT);

    if (draggedConnector != null
            && draggedConnector.getWidget() == VDDGridLayout.this) {
        return;
    }

    HorizontalDropLocation hl = getHorizontalDropLocation(cell, event);
    VerticalDropLocation vl = getVerticalDropLocation(cell, event);

    // Apply over style
    setStyleName(dragShadow.getElement(), OVER, true);

    // Add vertical location dependent style
    setStyleName(dragShadow.getElement(),
            OVER + "-" + vl.toString().toLowerCase(), true);

    // Add horizontal location dependent style
    setStyleName(dragShadow.getElement(),
            OVER + "-" + hl.toString().toLowerCase(), true);

}
 

/**
 * Adds a new tab from the drop
 * 
 * @param event
 *            The drag and drop event
 */
@Override
protected void handleDropFromLayout(DragAndDropEvent event) {
    LayoutBoundTransferable transferable = (LayoutBoundTransferable) event
            .getTransferable();

    // Get the target details
    AccordionTargetDetails details = (AccordionTargetDetails) event
            .getTargetDetails();
    DDAccordion acc = (DDAccordion) details.getTarget();
    Component c = transferable.getComponent();
    int idx = details.getOverIndex();
    VerticalDropLocation location = details.getDropLocation();

    // Detach from old source
    Component source = transferable.getSourceComponent();
    if (source instanceof ComponentContainer) {
        ((ComponentContainer) source).removeComponent(c);
    } else if (source instanceof SingleComponentContainer) {
        ((SingleComponentContainer) source).setContent(null);
    }

    if (location == VerticalDropLocation.TOP) {
        acc.addTab(c, idx);
    } else if (location == VerticalDropLocation.BOTTOM) {
        acc.addTab(c, idx + 1);
    } else {
        acc.addTab(c);
    }
}
 

/**
 * Removes any emphasis previously set by emphasis
 */
protected void deEmphasis() {

    setStyleName(dragShadow.getElement(), OVER, false);

    // Horizontal styles
    setStyleName(dragShadow.getElement(),
            OVER + "-"
                    + HorizontalDropLocation.LEFT.toString().toLowerCase(),
            false);
    setStyleName(dragShadow.getElement(), OVER + "-"
            + HorizontalDropLocation.CENTER.toString().toLowerCase(),
            false);
    setStyleName(dragShadow.getElement(),
            OVER + "-"
                    + HorizontalDropLocation.RIGHT.toString().toLowerCase(),
            false);

    // Vertical styles
    setStyleName(dragShadow.getElement(),
            OVER + "-" + VerticalDropLocation.TOP.toString().toLowerCase(),
            false);
    setStyleName(dragShadow.getElement(),
            OVER + "-"
                    + VerticalDropLocation.MIDDLE.toString().toLowerCase(),
            false);
    setStyleName(dragShadow.getElement(),
            OVER + "-"
                    + VerticalDropLocation.BOTTOM.toString().toLowerCase(),
            false);

}
 

private void initTree() {
	this.setSizeFull();
	this.setImmediate(true);
	this.setSelectable(true);
	this.addItemClickListener(this);
	this.addContainerProperty("", String.class, null);
	this.addContainerProperty(ACTIONS, HorizontalLayout.class, null	);
	this.addItem(new Object[] {TOOL, getActionLayout(false, false, TOOL)}, TOOL);
	this.setItemDescriptionGenerator(new ItemDescriptionGenerator() {
		private static final long serialVersionUID = -1913286695570843896L;

		@Override
		public String generateDescription(Component source, Object itemId,
				Object propertyId) {
			String description = "Show all ";
			if(itemId.equals(TOOL))
				description += "elements";
			else if (itemId.equals(INPUTS))
				description += "inputs";
			else if (itemId.equals(OUTPUTS))
				description += "outputs";
			else if (itemId.equals(PARAMETERS))
				description += "parameters";
			else
				return null;
			return description;
		}
	});
	this.setCollapsed(TOOL, false);
	String[] rootToolElements = new String[] {INPUTS, OUTPUTS, PARAMETERS};
	for(String element : rootToolElements) {
		this.addItem(new Object[] {element, getActionLayout(true, false, element)}, element);
		this.setParent(element, TOOL);
		this.setCollapsed(element, false);
	}
	this.setDragMode(TableDragMode.ROW);
	this.setDropHandler(new DropHandler() {
		private static final long serialVersionUID = -4415321436294383112L;

		@Override
		public AcceptCriterion getAcceptCriterion() {
			return new Or(Tree.TargetItemAllowsChildren.get(), new Not(VerticalLocationIs.MIDDLE));
		}
		
		@Override
		public void drop(DragAndDropEvent event) {
            final Transferable t = event.getTransferable();
            if (t.getSourceComponent() != TreeToolEditor.this
                    || !(t instanceof DataBoundTransferable)) {
                return;
            }

            final AbstractSelectTargetDetails dropData = ((AbstractSelectTargetDetails) event.getTargetDetails());

            final Object sourceItemId = ((DataBoundTransferable) t).getItemId();
            final Object targetItemId = dropData.getItemIdOver();
            final VerticalDropLocation location = dropData.getDropLocation();

            moveNode(sourceItemId, targetItemId, location);
		}
	});

}
 

@Override
protected void handleDropFromLayout(DragAndDropEvent event) {
    LayoutBoundTransferable transferable = (LayoutBoundTransferable) event
            .getTransferable();
    FormLayoutTargetDetails details = (FormLayoutTargetDetails) event
            .getTargetDetails();
    AbstractOrderedLayout layout = (AbstractOrderedLayout) details
            .getTarget();
    Component source = event.getTransferable().getSourceComponent();
    int idx = details.getOverIndex();
    Component comp = transferable.getComponent();

    // Check that we are not dragging an outer layout into an inner
    // layout
    Component parent = layout.getParent();
    while (parent != null) {
        if (parent == comp) {
            return;
        }
        parent = parent.getParent();
    }

    // Detach from old source
    if (source instanceof ComponentContainer) {
        ((ComponentContainer) source).removeComponent(comp);
    } else if (source instanceof SingleComponentContainer) {
        ((SingleComponentContainer) source).setContent(null);
    }

    // Increase index if component is dropped after or above a
    // previous
    // component
    VerticalDropLocation loc = (details).getDropLocation();
    if (loc == VerticalDropLocation.MIDDLE
            || loc == VerticalDropLocation.BOTTOM) {
        idx++;
    }

    // Add component
    if (idx >= 0) {
        layout.addComponent(comp, idx);
    } else {
        layout.addComponent(comp);
    }

    // Add component alignment if given
    if (dropAlignment != null) {
        layout.setComponentAlignment(comp, dropAlignment);
    }
}
 

@Override
protected void handleComponentReordering(DragAndDropEvent event) {
    LayoutBoundTransferable transferable = (LayoutBoundTransferable) event
            .getTransferable();
    FormLayoutTargetDetails details = (FormLayoutTargetDetails) event
            .getTargetDetails();
    DDFormLayout layout = (DDFormLayout) details.getTarget();

    Component comp = transferable.getComponent();
    int idx = details.getOverIndex();
    int oldIdx = layout.getComponentIndex(comp);

    if (idx == oldIdx) {
        // Dropping on myself
        return;
    }

    // Detach
    layout.removeComponent(comp);
    if (idx > 0 && idx > oldIdx) {
        idx--;
    }

    // Increase index if component is dropped after or above a previous
    // component
    VerticalDropLocation loc = details.getDropLocation();
    if (loc == VerticalDropLocation.MIDDLE
            || loc == VerticalDropLocation.BOTTOM) {
        idx++;
    }

    // Add component
    if (idx >= 0) {
        layout.addComponent(comp, idx);
    } else {
        layout.addComponent(comp);
    }

    // Add component alignment if given
    if (dropAlignment != null) {
        layout.setComponentAlignment(comp, dropAlignment);
    }
}
 

@Override
protected void handleDropFromLayout(DragAndDropEvent event) {
    LayoutBoundTransferable transferable = (LayoutBoundTransferable) event
            .getTransferable();
    CssLayoutTargetDetails details = (CssLayoutTargetDetails) event
            .getTargetDetails();
    DDCssLayout layout = (DDCssLayout) details.getTarget();
    HorizontalDropLocation hl = details.getHorizontalDropLocation();
    VerticalDropLocation vl = details.getVerticalDropLocation();
    Component source = event.getTransferable().getSourceComponent();
    int idx = (details).getOverIndex();
    Component comp = transferable.getComponent();
    Component over = details.getOverComponent();

    if (over == layout) {
        if (vl == VerticalDropLocation.TOP
                || hl == HorizontalDropLocation.LEFT) {
            idx = 0;
        } else if (vl == VerticalDropLocation.BOTTOM
                || hl == HorizontalDropLocation.RIGHT) {
            idx = -1;
        }
    } else {
        if (vl == VerticalDropLocation.BOTTOM
                || hl == HorizontalDropLocation.RIGHT) {
            idx++;
        }
    }

    // Check that we are not dragging an outer layout into an inner
    // layout
    Component parent = layout.getParent();
    while (parent != null) {
        if (parent == comp) {
            return;
        }
        parent = parent.getParent();
    }

    // If source is an instance of a component container then remove
    // it
    // from there,
    // the component cannot have two parents.
    if (source instanceof ComponentContainer) {
        ComponentContainer sourceLayout = (ComponentContainer) source;
        sourceLayout.removeComponent(comp);
    }

    // Add component
    if (idx >= 0 && idx < layout.getComponentCount()) {
        layout.addComponent(comp, idx);
    } else {
        layout.addComponent(comp);
    }
}
 

/**
 * Handle a drop from another layout
 * 
 * @param event
 *            The drag and drop event
 */
@Override
protected void handleDropFromLayout(DragAndDropEvent event) {
    LayoutBoundTransferable transferable = (LayoutBoundTransferable) event
            .getTransferable();
    VerticalLayoutTargetDetails details = (VerticalLayoutTargetDetails) event
            .getTargetDetails();
    AbstractOrderedLayout layout = (AbstractOrderedLayout) details
            .getTarget();
    Component source = event.getTransferable().getSourceComponent();
    int idx = (details).getOverIndex();
    Component comp = transferable.getComponent();

    // Check that we are not dragging an outer layout into an inner
    // layout
    Component parent = layout.getParent();
    while (parent != null) {
        if (parent == comp) {
            return;
        }
        parent = parent.getParent();
    }

    // Detach from old source
    if (source instanceof ComponentContainer) {
        ((ComponentContainer) source).removeComponent(comp);
    } else if (source instanceof SingleComponentContainer) {
        ((SingleComponentContainer) source).setContent(null);
    }

    // Increase index if component is dropped after or above a
    // previous
    // component
    VerticalDropLocation loc = (details).getDropLocation();
    if (loc == VerticalDropLocation.MIDDLE
            || loc == VerticalDropLocation.BOTTOM) {
        idx++;
    }

    // Add component
    if (idx >= 0) {
        layout.addComponent(comp, idx);
    } else {
        layout.addComponent(comp);
    }

    // Add component alignment if given
    if (dropAlignment != null) {
        layout.setComponentAlignment(comp, dropAlignment);
    }
}
 

/**
 * Called when a component changed location within the layout
 * 
 * @param event
 *            The drag and drop event
 */
@Override
protected void handleComponentReordering(DragAndDropEvent event) {
    // Component re-ordering
    LayoutBoundTransferable transferable = (LayoutBoundTransferable) event
            .getTransferable();
    VerticalLayoutTargetDetails details = (VerticalLayoutTargetDetails) event
            .getTargetDetails();
    AbstractOrderedLayout layout = (AbstractOrderedLayout) details
            .getTarget();
    Component comp = transferable.getComponent();
    int idx = details.getOverIndex();
    int oldIndex = layout.getComponentIndex(comp);

    if (idx == oldIndex) {
        // Index did not change
        return;
    }

    // Detach
    layout.removeComponent(comp);

    // Account for detachment if new index is bigger then old index
    if (idx > oldIndex) {
        idx--;
    }

    // Increase index if component is dropped after or above a previous
    // component
    VerticalDropLocation loc = details.getDropLocation();
    if (loc == VerticalDropLocation.MIDDLE
            || loc == VerticalDropLocation.BOTTOM) {
        idx++;
    }

    // Add component
    if (idx >= 0) {
        layout.addComponent(comp, idx);
    } else {
        layout.addComponent(comp);
    }

    // Add component alignment if given
    if (dropAlignment != null) {
        layout.setComponentAlignment(comp, dropAlignment);
    }

}