/*
* Ext GWT 2.2.4 - Ext for GWT
* Copyright(c) 2007-2010, Ext JS, LLC.
* licensing@extjs.com
*
* http://extjs.com/license
*/
package com.extjs.gxt.ui.client.dnd;
import java.util.List;
import com.extjs.gxt.ui.client.core.El;
import com.extjs.gxt.ui.client.data.ModelData;
import com.extjs.gxt.ui.client.dnd.DND.Feedback;
import com.extjs.gxt.ui.client.event.DNDEvent;
import com.extjs.gxt.ui.client.util.Rectangle;
import com.extjs.gxt.ui.client.widget.ListView;
import com.google.gwt.user.client.Element;
/**
* A <code>DropTarget</code> implementation for the ListView component.
*
* Supported drag data:
* <ul>
* <li>A single ModelData instance.</li>
* <li>A List of ModelData instances.</li>
* <li>A List of TreeStoreModel instances (children are ignored).
* </ul>
*/
public class ListViewDropTarget extends DropTarget {
protected ListView<ModelData> listView;
protected int insertIndex;
protected ModelData activeItem;
protected boolean before;
private boolean autoSelect;
/**
* Creates a new list view drop target instance.
*
* @param listView the target list view
*/
@SuppressWarnings({"unchecked", "rawtypes"})
public ListViewDropTarget(ListView listView) {
super(listView);
this.listView = listView;
}
/**
* Returns the target's list view component.
*
* @return the list view
*/
public ListView<ModelData> getListView() {
return listView;
}
/**
* Returns true if auto select is enabled.
*
* @return the auto select state
*/
public boolean isAutoSelect() {
return autoSelect;
}
@Override
protected void onDragDrop(DNDEvent e) {
super.onDragDrop(e);
Object data = e.getData();
List<ModelData> models = prepareDropData(data, true);
if (models.size() > 0) {
if (feedback == Feedback.APPEND) {
listView.getStore().add(models);
} else {
listView.getStore().insert(models, insertIndex);
}
}
insertIndex = -1;
activeItem = null;
}
@Override
protected void onDragEnter(DNDEvent e) {
super.onDragEnter(e);
e.setCancelled(false);
e.getStatus().setStatus(true);
}
@Override
protected void onDragLeave(DNDEvent e) {
super.onDragLeave(e);
Insert insert = Insert.get();
insert.setVisible(false);
}
@Override
protected void onDragMove(DNDEvent event) {
if (!event.within(listView.getElement())) {
event.setCancelled(true);
event.getStatus().setStatus(false);
return;
}
event.setCancelled(false);
event.getStatus().setStatus(true);
}
/**
* True to automatically select and new items created after a drop (defaults
* to false).
*
* @param autoSelect true to auto select
*/
public void setAutoSelect(boolean autoSelect) {
this.autoSelect = autoSelect;
}
@Override
protected void showFeedback(DNDEvent event) {
event.getStatus().setStatus(true);
if (feedback == Feedback.INSERT) {
event.getStatus().setStatus(true);
Element row = listView.findElement(event.getTarget()).cast();
if (row == null && listView.getStore().getCount() > 0) {
row = listView.getElement(listView.getStore().getCount() - 1).cast();
}
if (row != null) {
int height = row.getOffsetHeight();
int mid = height / 2;
mid += row.getAbsoluteTop();
int y = event.getClientY();
before = y < mid;
int idx = listView.findElementIndex(row);
activeItem = listView.getStore().getAt(idx);
insertIndex = adjustIndex(event, idx);
showInsert(event, row);
} else {
insertIndex = 0;
}
}
}
private int adjustIndex(DNDEvent event, int index) {
Object data = event.getData();
int i = index;
List<ModelData> models = prepareDropData(data, true);
for (ModelData m : models) {
int idx = listView.getStore().indexOf(m);
if (idx > -1 && (before ? idx < index : idx <= index)) {
i--;
}
}
return before ? i : i + 1;
}
protected void showInsert(DNDEvent event, Element row) {
Insert insert = Insert.get();
insert.show(row);
Rectangle rect = El.fly(row).getBounds();
int y = !before ? (rect.y + rect.height - 4) : rect.y - 2;
insert.el().setBounds(rect.x, y, rect.width, 6);
}
}