eclipseprojects/eu.etaxonomy.taxeditor/src/eu/etaxonomy/taxeditor/editor/GroupedComposite.java

   1 package eu.etaxonomy.taxeditor.editor;
   2
   3 import org.eclipse.swt.SWT;
   4 import org.eclipse.swt.dnd.DND;
   5 import org.eclipse.swt.dnd.DragSource;
   6 import org.eclipse.swt.dnd.DragSourceAdapter;
   7 import org.eclipse.swt.dnd.DragSourceEvent;
   8 import org.eclipse.swt.dnd.DragSourceListener;
   9 import org.eclipse.swt.dnd.Transfer;
  10 import org.eclipse.swt.widgets.Composite;
  11 import org.eclipse.swt.widgets.Control;
  12
  13 import eu.etaxonomy.taxeditor.actions.WidgetTransfer;
  14
  15 /**
  16  * A composite which can be dragged between different EditorGroupComposite. The user
  17  * uses the draggable control for dragging the whole composite.
  18  *
  19  * @see eu.etaxonomy.taxeditor.editor.EditorGroupComposite
  20  *
  21  * @author p.ciardelli
  22  *
  23  */
  24 abstract public class GroupedComposite extends Composite {
  25
  26         IParentDataAdapter parentDataAdapter;
  27         private Control draggableControl;
  28
  29         public GroupedComposite(Composite parent) {
  30                 super(parent, SWT.NONE);
  31
  32                 createContent();
  33         }
  34
  35         abstract protected void createContent();
  36
  37         protected void setDraggableControl(Control control) {
  38                 draggableControl = control;
  39         }
  40
  41         public void setDraggable(boolean draggable) {
  42
  43                 if (draggable) {
  44
  45                         if (dragger != null) {
  46                                 // Already initalized
  47                                 return;
  48                         }
  49
  50                         if (draggableControl == null) {
  51                                 throw new NullPointerException(
  52                                                 "Draggable control must be set to add draggability");
  53                         }
  54
  55                         Transfer[] types = new Transfer[] { WidgetTransfer.getInstance() };
  56                         int operations = DND.DROP_MOVE | DND.DROP_COPY | DND.DROP_LINK;
  57
  58                         dragger = new DragSource(draggableControl, operations);
  59                         dragger.setTransfer(types);
  60                         dragger.addDragListener(dragSourceListener);
  61
  62                 } else {
  63                         dragger = null;
  64                 }
  65         }
  66
  67         /**
  68          * Drag listener which passes the Composite as the data in a drag event.
  69          */
  70         DragSourceListener dragSourceListener = new DragSourceAdapter() {
  71
  72                 public void dragStart(DragSourceEvent event) {
  73                         GroupedComposite.this.setFocus();
  74                         event.doit = true;
  75                 }
  76
  77                 public void dragSetData(DragSourceEvent event) {
  78                         WidgetTransfer.getInstance().setWidget(GroupedComposite.this);
  79                 }
  80         };
  81         private DragSource dragger;
  82
  83         /**
  84          * Override of setParent: dispose of parent if this is its last child
  85          * composite
  86          *
  87          * @see org.eclipse.swt.widgets.Control#setParent(org.eclipse.swt.widgets.Composite)
  88          */
  89         public boolean setParent(Composite parent) {
  90
  91                 Composite oldParent = this.getParent();
  92                 Composite oldGrandparent = oldParent.getParent();
  93
  94                 if (super.setParent(parent)) {
  95                         if (oldParent instanceof EditorGroupComposite
  96                                         && oldParent.getChildren().length == 0) {
  97                                 oldParent.dispose();
  98                         }
  99                         adaptParentData();
 100
 101                         // Redraw the component holding the group and grouped composites
 102                         parent.getParent().layout();
 103
 104                         // In case we are dragging between different views, redraw the
 105                         //      "old" view
 106                         if (!oldGrandparent.equals(parent.getParent())) {
 107                                 oldGrandparent.layout();
 108                         }
 109
 110                         return true;
 111                 }
 112                 return false;
 113         }
 114
 115         public void dispose () {
 116                 Composite parent = this.getParent();
 117                 Composite grandParent = null;
 118                 if (parent != null) {
 119                         grandParent = parent.getParent();
 120                 }
 121                 super.dispose();
 122                 if (parent instanceof Composite
 123                                 && parent.getChildren().length == 0) {
 124                         parent.dispose();
 125                 }
 126
 127                 // Redraw the component holding the group and grouped composites
 128                 if (grandParent != null) {
 129                         grandParent.layout();
 130                 }
 131         }
 132
 133         /**
 134          * A grouped composite is usually grouped according to data held by its
 135          * parent. When the composite changes parents, this method gets called to
 136          * update data as needed.
 137          */
 138         protected void adaptParentData() {
 139                 if (parentDataAdapter != null) {
 140                         parentDataAdapter.adaptParentData();
 141                 }
 142         }
 143
 144         public void setParentDataAdapter(IParentDataAdapter parentDataAdapter) {
 145                 this.parentDataAdapter = parentDataAdapter;
 146         }
 147 }