com.extjs.gxt.ui.client.dnd.TreeGridDragSource.java Source code

Introduction

Here is the source code for com.extjs.gxt.ui.client.dnd.TreeGridDragSource.java

Source

/*
 * Sencha GXT 2.3.1 - Sencha for GWT
 * Copyright(c) 2007-2013, Sencha, Inc.
 * licensing@sencha.com
 * 
 * http://www.sencha.com/products/gxt/license/
 */
package com.extjs.gxt.ui.client.dnd;

import java.util.ArrayList;
import java.util.List;

import com.extjs.gxt.ui.client.data.ModelData;
import com.extjs.gxt.ui.client.data.TreeModel;
import com.extjs.gxt.ui.client.dnd.DND.Operation;
import com.extjs.gxt.ui.client.dnd.DND.TreeSource;
import com.extjs.gxt.ui.client.event.DNDEvent;
import com.extjs.gxt.ui.client.util.Format;
import com.extjs.gxt.ui.client.widget.Component;
import com.extjs.gxt.ui.client.widget.treegrid.TreeGrid;
import com.extjs.gxt.ui.client.widget.treegrid.TreeGrid.TreeNode;
import com.google.gwt.safehtml.shared.SafeHtmlUtils;
import com.google.gwt.user.client.Element;

/**
 * <code>DragSource</code> implementation for TreeGrid.
 */
public class TreeGridDragSource extends DragSource {

    protected TreeGrid<ModelData> treeGrid;
    protected TreeSource treeGridSource = TreeSource.BOTH;

    @SuppressWarnings("unchecked")
    public TreeGridDragSource(Component component) {
        super(component);
        treeGrid = (TreeGrid<ModelData>) component;
        setStatusText("{0} items selected");
    }

    /**
     * Returns the type if items that can be dragged.
     * 
     * @return the tree source type
     */
    public TreeSource getTreeGridSource() {
        return treeGridSource;
    }

    /**
     * Sets which tree items can be dragged (defaults to BOTH).
     * 
     * @param treeGridSource the tree source type
     */
    public void setTreeGridSource(TreeSource treeGridSource) {
        this.treeGridSource = treeGridSource;
    }

    @Override
    protected void onDragDrop(DNDEvent event) {
        if (event.getOperation() == Operation.MOVE) {
            List<TreeModel> sel = event.getData();
            for (TreeModel tm : sel) {
                ModelData m = (ModelData) tm.get("model");
                treeGrid.getTreeStore().remove(m);
            }
        }
    }

    @Override
    @SuppressWarnings({ "unchecked", "rawtypes" })
    protected void onDragStart(DNDEvent e) {
        TreeNode n = treeGrid.findNode((Element) e.getDragEvent().getStartElement());
        if (n == null) {
            e.setCancelled(true);
            return;
        }
        ModelData m = n.getModel();
        if (!treeGrid.getTreeView().isSelectableTarget(m, (Element) e.getDragEvent().getStartElement())) {
            e.setCancelled(true);
            return;
        }

        boolean leaf = treeGridSource == TreeSource.LEAF || treeGridSource == TreeSource.BOTH;
        boolean node = treeGridSource == TreeSource.NODE || treeGridSource == TreeSource.BOTH;

        List<ModelData> sel = treeGrid.getSelectionModel().getSelectedItems();
        if (sel.size() > 0) {
            boolean ok = true;
            for (ModelData mi : sel) {
                if ((leaf && treeGrid.isLeaf(mi)) || (node && !treeGrid.isLeaf(mi))) {
                    continue;
                }
                ok = false;
                break;
            }
            if (ok) {
                List models = new ArrayList();
                for (ModelData mi : sel) {
                    models.add(treeGrid.getTreeStore().getModelState(mi));
                }
                e.setData(models);
                e.setCancelled(false);
                e.getStatus()
                        .update(SafeHtmlUtils.fromTrustedString(Format.substitute(getStatusText(), sel.size())));

            } else {
                e.setCancelled(true);
            }
        } else {
            e.setCancelled(true);
        }
    }

}