DefaultCssLayoutDropHandler.java

/*
 * Copyright 2012 John Ahlroos
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package fi.jasoft.dragdroplayouts.drophandlers;

import com.vaadin.event.dd.DragAndDropEvent;
import com.vaadin.event.dd.DropHandler;
import com.vaadin.event.dd.acceptcriteria.AcceptAll;
import com.vaadin.event.dd.acceptcriteria.AcceptCriterion;
import com.vaadin.terminal.gwt.client.ui.dd.HorizontalDropLocation;
import com.vaadin.terminal.gwt.client.ui.dd.VerticalDropLocation;
import com.vaadin.ui.AbstractOrderedLayout;
import com.vaadin.ui.Component;
import com.vaadin.ui.ComponentContainer;

import fi.jasoft.dragdroplayouts.DDAbsoluteLayout;
import fi.jasoft.dragdroplayouts.DDCssLayout;
import fi.jasoft.dragdroplayouts.DDCssLayout.CssLayoutTargetDetails;
import fi.jasoft.dragdroplayouts.DDHorizontalLayout.HorizontalLayoutTargetDetails;
import fi.jasoft.dragdroplayouts.DDVerticalLayout.VerticalLayoutTargetDetails;
import fi.jasoft.dragdroplayouts.events.LayoutBoundTransferable;
import fi.jasoft.dragdroplayouts.events.VerticalLocationIs;

/**
 * Default CSS Layout drop handler
 * 
 * @author John Ahlroos / www.jasoft.fi
 * @since 0.7.0
 * 
 */
@SuppressWarnings("serial")
public class DefaultCssLayoutDropHandler extends
		AbstractDefaultLayoutDropHandler {

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * fi.jasoft.dragdroplayouts.drophandlers.AbstractDefaultLayoutDropHandler
	 * #handleComponentReordering(com.vaadin.event.dd.DragAndDropEvent)
	 */
	@Override
	protected void handleComponentReordering(DragAndDropEvent event) {
		// Component re-ordering
		LayoutBoundTransferable transferable = (LayoutBoundTransferable) event
				.getTransferable();
		CssLayoutTargetDetails details = (CssLayoutTargetDetails) event
				.getTargetDetails();
		DDCssLayout layout = (DDCssLayout) details.getTarget();
		Component comp = transferable.getComponent();
		int idx = details.getOverIndex();
		Component over = details.getOverComponent();
		
		// Detach
		layout.removeComponent(comp);

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

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * fi.jasoft.dragdroplayouts.drophandlers.AbstractDefaultLayoutDropHandler
	 * #handleDropFromLayout(com.vaadin.event.dd.DragAndDropEvent)
	 */
	@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);
		}
	}
}