bundles/org.simantics.browsing.ui.swt/src/org/simantics/browsing/ui/swt/widgets/impl/SelectionListenerImpl.java

   1 /*******************************************************************************\r
   2  * Copyright (c) 2007, 2012 Association for Decentralized Information Management\r
   3  * in Industry THTH ry.\r
   4  * All rights reserved. This program and the accompanying materials\r
   5  * are made available under the terms of the Eclipse Public License v1.0\r
   6  * which accompanies this distribution, and is available at\r
   7  * http://www.eclipse.org/legal/epl-v10.html\r
   8  *\r
   9  * Contributors:\r
  10  *     VTT Technical Research Centre of Finland - initial API and implementation\r
  11  *******************************************************************************/\r
  12 package org.simantics.browsing.ui.swt.widgets.impl;\r
  13 \r
  14 import org.eclipse.jface.viewers.ISelection;\r
  15 import org.eclipse.swt.events.SelectionEvent;\r
  16 import org.eclipse.swt.events.SelectionListener;\r
  17 import org.simantics.db.WriteGraph;\r
  18 import org.simantics.db.common.request.WriteRequest;\r
  19 import org.simantics.db.exception.DatabaseException;\r
  20 import org.simantics.db.management.ISessionContext;\r
  21 import org.simantics.utils.ReflectionUtils;\r
  22 import org.simantics.utils.ui.ISelectionUtils;\r
  23 \r
  24 abstract public class SelectionListenerImpl<T> implements SelectionListener, Widget {\r
  25 \r
  26         private ISessionContext context;\r
  27         private Object lastInput = null;\r
  28         \r
  29     final private Class<?> clazz;\r
  30         \r
  31         public SelectionListenerImpl(ISessionContext context) {\r
  32                 this.context = context;\r
  33         clazz = ReflectionUtils.getSingleParameterType(getClass());\r
  34         }\r
  35         \r
  36         @Override\r
  37         public void widgetDefaultSelected(SelectionEvent e) {\r
  38                 widgetSelected(e);\r
  39         }\r
  40         \r
  41         @Override\r
  42         public void widgetSelected(SelectionEvent e) {\r
  43                 \r
  44                 final Object input = lastInput;\r
  45                 \r
  46                 try {\r
  47                     @SuppressWarnings("unchecked")\r
  48             T single = (T) ISelectionUtils.filterSingleSelection((ISelection)input, clazz);\r
  49                         beforeApply(single);\r
  50                         \r
  51                         context.getSession().syncRequest(new WriteRequest() {\r
  52 \r
  53                                 @SuppressWarnings("unchecked")\r
  54                 @Override\r
  55                                 public void perform(WriteGraph graph) throws DatabaseException {\r
  56                                     graph.markUndoPoint();\r
  57                                         T single = (T) ISelectionUtils.filterSingleSelection((ISelection)input, clazz);\r
  58                                         apply(graph, single);\r
  59                                 }\r
  60                                 \r
  61                         });\r
  62                 } catch (DatabaseException e1) {\r
  63                         e1.printStackTrace();\r
  64                 }\r
  65         }\r
  66 \r
  67         @Override\r
  68         public void setInput(ISessionContext context, Object parameter) {\r
  69                 this.context = context;\r
  70                 lastInput = parameter;\r
  71         }\r
  72         \r
  73         public void beforeApply() {\r
  74                 \r
  75         }\r
  76         \r
  77     public void beforeApply(T input) {\r
  78         beforeApply();\r
  79     }\r
  80 \r
  81         abstract public void apply(WriteGraph graph, T input) throws DatabaseException;\r
  82         \r
  83 }\r
  84