Java tutorial
/* @VaadinApache2LicenseForJavaFiles@ */ /** * */ package com.vaadin.terminal.gwt.client.ui.dd; import com.google.gwt.user.client.ui.Widget; import com.vaadin.terminal.gwt.client.UIDL; import com.vaadin.terminal.gwt.client.ui.VTree; import com.vaadin.terminal.gwt.client.ui.VTree.TreeNode; final public class VTargetInSubtree extends VAcceptCriterion { @Override protected boolean accept(VDragEvent drag, UIDL configuration) { VTree tree = (VTree) VDragAndDropManager.get().getCurrentDropHandler().getPaintable(); TreeNode treeNode = tree.getNodeByKey((String) drag.getDropDetails().get("itemIdOver")); if (treeNode != null) { Widget parent2 = treeNode; int depth = configuration.getIntAttribute("depth"); if (depth < 0) { depth = Integer.MAX_VALUE; } final String searchedKey = configuration.getStringAttribute("key"); for (int i = 0; i <= depth && parent2 instanceof TreeNode; i++) { if (searchedKey.equals(((TreeNode) parent2).key)) { return true; } // panel -> next level node parent2 = parent2.getParent().getParent(); } } return false; } }