org.eclipse.linuxtools.tmf.ui/src/org/eclipse/linuxtools/tmf/ui/views/filter/FilterDropTargetAdapter.java

   1 /*******************************************************************************
   2  * Copyright (c) 2013 Kalray
   3  *
   4  * All rights reserved. This program and the accompanying materials are
   5  * made available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *   Xavier Raynaud - Initial API and implementation
  11  *******************************************************************************/
  12
  13 package org.eclipse.linuxtools.tmf.ui.views.filter;
  14
  15
  16 import org.eclipse.jface.util.LocalSelectionTransfer;
  17 import org.eclipse.linuxtools.tmf.core.filter.model.ITmfFilterTreeNode;
  18 import org.eclipse.linuxtools.tmf.core.filter.model.TmfFilterNode;
  19 import org.eclipse.swt.dnd.DND;
  20 import org.eclipse.swt.dnd.DropTargetAdapter;
  21 import org.eclipse.swt.dnd.DropTargetEvent;
  22 import org.eclipse.swt.widgets.TreeItem;
  23
  24 /**
  25  * DropTargetListener for filter view
  26  * @author Xavier Raynaud <xavier.raynaud@kalray.eu>
  27  */
  28 class FilterDropTargetAdapter extends DropTargetAdapter {
  29
  30     private FilterViewer fViewer;
  31
  32     /**
  33      * Constructor
  34      * @param viewer the content of the FilterView
  35      */
  36     public FilterDropTargetAdapter(FilterViewer viewer) {
  37         super();
  38         this.fViewer = viewer;
  39     }
  40
  41     /**
  42      * Returns <code>true</code> if droppedNode is an ancestor of node.
  43      *
  44      * @param droppedNode
  45      *            the ITmfFilterTreeNode to drop or paste
  46      * @param node
  47      *            the ITmfFilterTreeNode receiving a new child
  48      * @return <code>true</code> if droppedNode is and ancestor of node,
  49      *         <code>false</code> otherwise.
  50      */
  51     private static boolean isAncestor(ITmfFilterTreeNode droppedNode, ITmfFilterTreeNode node) {
  52         ITmfFilterTreeNode tmp = node;
  53
  54         while (tmp != null) {
  55             ITmfFilterTreeNode n = tmp.getParent();
  56             if (n == droppedNode) {
  57                 return true;
  58             }
  59             tmp = n;
  60         }
  61         return false;
  62     }
  63
  64     @Override
  65     public void dropAccept(DropTargetEvent event) {
  66         ITmfFilterTreeNode treeNodeToDrop = null;
  67         if (LocalSelectionTransfer.getTransfer().isSupportedType(event.currentDataType)) {
  68             treeNodeToDrop = FilterEditUtils.getTransferredTreeNode();
  69         }
  70         if (treeNodeToDrop == null) {
  71             // should never occur
  72             event.detail = DND.DROP_NONE;
  73             return;
  74         }
  75         if (event.item instanceof TreeItem) {
  76             Object data = event.item.getData();
  77             if (data instanceof ITmfFilterTreeNode) {
  78                 ITmfFilterTreeNode node = (ITmfFilterTreeNode) data;
  79                 if (node.getValidChildren().contains(treeNodeToDrop.getNodeName())) {
  80                     if (isAncestor(treeNodeToDrop, node) && event.detail != DND.DROP_COPY) {
  81                         // do nothing in this case
  82                         event.detail = DND.DROP_NONE;
  83                     }
  84                     return;
  85                 }
  86             }
  87         } else { // accept only TmfFilterNode
  88             if (!TmfFilterNode.NODE_NAME.equals(treeNodeToDrop.getNodeName())) {
  89                 event.detail = DND.DROP_NONE;
  90             }
  91             return;
  92         }
  93         event.detail = DND.DROP_NONE;
  94         return;
  95     }
  96
  97     @Override
  98     public void drop(DropTargetEvent event) {
  99         ITmfFilterTreeNode treeNodeToDrop = FilterEditUtils.getTransferredTreeNode();
 100         if (event.item instanceof TreeItem) {
 101             Object data = event.item.getData();
 102             if (data instanceof ITmfFilterTreeNode) {
 103                 ITmfFilterTreeNode node = (ITmfFilterTreeNode) data;
 104                 if (node.getValidChildren().contains(treeNodeToDrop.getNodeName())) {
 105                     treeNodeToDrop = treeNodeToDrop.clone();
 106                     node.addChild(treeNodeToDrop);
 107                     fViewer.refresh();
 108                     fViewer.setSelection(treeNodeToDrop, true);
 109                     return;
 110                 }
 111             }
 112         } else { // accept only TmfFilterNode
 113             if (TmfFilterNode.NODE_NAME.equals(treeNodeToDrop.getNodeName())) {
 114                 ITmfFilterTreeNode root = fViewer.getInput();
 115                 treeNodeToDrop = treeNodeToDrop.clone();
 116                 root.addChild(treeNodeToDrop);
 117                 fViewer.refresh();
 118                 fViewer.setSelection(treeNodeToDrop, true);
 119                 return;
 120             }
 121         }
 122     }
 123
 124 }