AbstractPageViewer.java

   1 package org.argeo.cms.viewers;
   2
   3 import java.util.Observable;
   4 import java.util.Observer;
   5
   6 import javax.jcr.Node;
   7 import javax.jcr.RepositoryException;
   8 import javax.jcr.Session;
   9
  10 import org.apache.commons.logging.Log;
  11 import org.apache.commons.logging.LogFactory;
  12 import org.argeo.cms.CmsException;
  13 import org.argeo.cms.ui.CmsEditable;
  14 import org.argeo.cms.widgets.ScrolledPage;
  15 import org.eclipse.jface.viewers.ContentViewer;
  16 import org.eclipse.jface.viewers.ISelection;
  17 import org.eclipse.jface.viewers.StructuredSelection;
  18 import org.eclipse.swt.SWT;
  19 import org.eclipse.swt.events.FocusEvent;
  20 import org.eclipse.swt.events.FocusListener;
  21 import org.eclipse.swt.events.MouseAdapter;
  22 import org.eclipse.swt.events.MouseListener;
  23 import org.eclipse.swt.widgets.Composite;
  24 import org.eclipse.swt.widgets.Control;
  25 import org.eclipse.swt.widgets.Widget;
  26 import org.xml.sax.SAXParseException;
  27
  28 /** Base class for viewers related to a page */
  29 public abstract class AbstractPageViewer extends ContentViewer implements
  30                 Observer {
  31         private static final long serialVersionUID = 5438688173410341485L;
  32
  33         private final static Log log = LogFactory.getLog(AbstractPageViewer.class);
  34
  35         private final boolean readOnly;
  36         /** The basis for the layouts, typically a ScrolledPage. */
  37         private final Composite page;
  38         private final CmsEditable cmsEditable;
  39
  40         private MouseListener mouseListener;
  41         private FocusListener focusListener;
  42
  43         private EditablePart edited;
  44         private ISelection selection = StructuredSelection.EMPTY;
  45
  46         protected AbstractPageViewer(Section parent, int style,
  47                         CmsEditable cmsEditable) {
  48                 // read only at UI level
  49                 readOnly = SWT.READ_ONLY == (style & SWT.READ_ONLY);
  50
  51                 this.cmsEditable = cmsEditable == null ? CmsEditable.NON_EDITABLE
  52                                 : cmsEditable;
  53                 if (this.cmsEditable instanceof Observable)
  54                         ((Observable) this.cmsEditable).addObserver(this);
  55
  56                 if (cmsEditable.canEdit()) {
  57                         mouseListener = createMouseListener();
  58                         focusListener = createFocusListener();
  59                 }
  60                 page = findPage(parent);
  61         }
  62
  63         /**
  64          * Can be called to simplify the called to isModelInitialized() and
  65          * initModel()
  66          */
  67         protected void initModelIfNeeded(Node node) {
  68                 try {
  69                         if (!isModelInitialized(node))
  70                                 if (getCmsEditable().canEdit()) {
  71                                         initModel(node);
  72                                         node.getSession().save();
  73                                 }
  74                 } catch (Exception e) {
  75                         throw new CmsException("Cannot initialize model", e);
  76                 }
  77         }
  78
  79         /** Called if user can edit and model is not initialized */
  80         protected Boolean isModelInitialized(Node node) throws RepositoryException {
  81                 return true;
  82         }
  83
  84         /** Called if user can edit and model is not initialized */
  85         protected void initModel(Node node) throws RepositoryException {
  86         }
  87
  88         /** Create (retrieve) the MouseListener to use. */
  89         protected MouseListener createMouseListener() {
  90                 return new MouseAdapter() {
  91                         private static final long serialVersionUID = 1L;
  92                 };
  93         }
  94
  95         /** Create (retrieve) the FocusListener to use. */
  96         protected FocusListener createFocusListener() {
  97                 return new FocusListener() {
  98                         private static final long serialVersionUID = 1L;
  99
 100                         @Override
 101                         public void focusLost(FocusEvent event) {
 102                         }
 103
 104                         @Override
 105                         public void focusGained(FocusEvent event) {
 106                         }
 107                 };
 108         }
 109
 110         protected Composite findPage(Composite composite) {
 111                 if (composite instanceof ScrolledPage) {
 112                         return (ScrolledPage) composite;
 113                 } else {
 114                         if (composite.getParent() == null)
 115                                 return composite;
 116                         return findPage(composite.getParent());
 117                 }
 118         }
 119
 120         @Override
 121         public void update(Observable o, Object arg) {
 122                 if (o == cmsEditable)
 123                         editingStateChanged(cmsEditable);
 124         }
 125
 126         /** To be overridden in order to provide the actual refresh */
 127         protected void refresh(Control control) throws RepositoryException {
 128         }
 129
 130         /** To be overridden.Save the edited part. */
 131         protected void save(EditablePart part) throws RepositoryException {
 132         }
 133
 134         /** Prepare the edited part */
 135         protected void prepare(EditablePart part, Object caretPosition) {
 136         }
 137
 138         /** Notified when the editing state changed. Does nothing, to be overridden */
 139         protected void editingStateChanged(CmsEditable cmsEditable) {
 140         }
 141
 142         @Override
 143         public void refresh() {
 144                 try {
 145                         if (cmsEditable.canEdit() && !readOnly)
 146                                 mouseListener = createMouseListener();
 147                         else
 148                                 mouseListener = null;
 149                         refresh(getControl());
 150                         layout(getControl());
 151                 } catch (RepositoryException e) {
 152                         throw new CmsException("Cannot refresh", e);
 153                 }
 154         }
 155
 156         @Override
 157         public void setSelection(ISelection selection, boolean reveal) {
 158                 this.selection = selection;
 159         }
 160
 161         protected void updateContent(EditablePart part) throws RepositoryException {
 162         }
 163
 164         // LOW LEVEL EDITION
 165         protected void edit(EditablePart part, Object caretPosition) {
 166                 try {
 167                         if (edited == part)
 168                                 return;
 169
 170                         if (edited != null && edited != part) {
 171                                 EditablePart previouslyEdited = edited;
 172                                 try {
 173                                         stopEditing(true);
 174                                 } catch (Exception e) {
 175                                         notifyEditionException(e);
 176                                         edit(previouslyEdited, caretPosition);
 177                                         return;
 178                                 }
 179                         }
 180
 181                         part.startEditing();
 182                         updateContent(part);
 183                         prepare(part, caretPosition);
 184                         edited = part;
 185                         layout(part.getControl());
 186                 } catch (RepositoryException e) {
 187                         throw new CmsException("Cannot edit " + part, e);
 188                 }
 189         }
 190
 191         private void stopEditing(Boolean save) throws RepositoryException {
 192                 if (edited instanceof Widget && ((Widget) edited).isDisposed()) {
 193                         edited = null;
 194                         return;
 195                 }
 196
 197                 assert edited != null;
 198                 if (edited == null) {
 199                         if (log.isTraceEnabled())
 200                                 log.warn("Told to stop editing while not editing anything");
 201                         return;
 202                 }
 203
 204                 if (save)
 205                         save(edited);
 206
 207                 edited.stopEditing();
 208                 updateContent(edited);
 209                 layout(((EditablePart) edited).getControl());
 210                 edited = null;
 211         }
 212
 213         // METHODS AVAILABLE TO EXTENDING CLASSES
 214         protected void saveEdit() {
 215                 try {
 216                         if (edited != null)
 217                                 stopEditing(true);
 218                 } catch (RepositoryException e) {
 219                         throw new CmsException("Cannot stop editing", e);
 220                 }
 221         }
 222
 223         protected void cancelEdit() {
 224                 try {
 225                         if (edited != null)
 226                                 stopEditing(false);
 227                 } catch (RepositoryException e) {
 228                         throw new CmsException("Cannot cancel editing", e);
 229                 }
 230         }
 231
 232         /** Layout this controls from the related base page. */
 233         public void layout(Control... controls) {
 234                 page.layout(controls);
 235         }
 236
 237         /**
 238          * Find the first {@link EditablePart} in the parents hierarchy of this
 239          * control
 240          */
 241         protected EditablePart findDataParent(Control parent) {
 242                 if (parent instanceof EditablePart) {
 243                         return (EditablePart) parent;
 244                 }
 245                 if (parent.getParent() != null)
 246                         return findDataParent(parent.getParent());
 247                 else
 248                         throw new CmsException("No data parent found");
 249         }
 250
 251         // UTILITIES
 252         /** Check whether the edited part is in a proper state */
 253         protected void checkEdited() {
 254                 if (edited == null || (edited instanceof Widget)
 255                                 && ((Widget) edited).isDisposed())
 256                         throw new CmsException(
 257                                         "Edited should not be null or disposed at this stage");
 258         }
 259
 260         /** Persist all changes. */
 261         protected void persistChanges(Session session) throws RepositoryException {
 262                 session.save();
 263                 session.refresh(false);
 264                 // TODO notify that changes have been persisted
 265         }
 266
 267         /** Convenience method using a Node in order to save the underlying session. */
 268         protected void persistChanges(Node anyNode) throws RepositoryException {
 269                 persistChanges(anyNode.getSession());
 270         }
 271
 272         /** Notify edition exception */
 273         protected void notifyEditionException(Throwable e) {
 274                 Throwable eToLog = e;
 275                 if (e instanceof IllegalArgumentException)
 276                         if (e.getCause() instanceof SAXParseException)
 277                                 eToLog = e.getCause();
 278                 log.error(eToLog.getMessage());
 279                 if (log.isTraceEnabled())
 280                         log.trace("Full stack of " + eToLog.getMessage(), e);
 281                 // TODO Light error notification popup
 282         }
 283
 284         // GETTERS / SETTERS
 285         public boolean isReadOnly() {
 286                 return readOnly;
 287         }
 288
 289         protected EditablePart getEdited() {
 290                 return edited;
 291         }
 292
 293         public MouseListener getMouseListener() {
 294                 return mouseListener;
 295         }
 296
 297         public FocusListener getFocusListener() {
 298                 return focusListener;
 299         }
 300
 301         public CmsEditable getCmsEditable() {
 302                 return cmsEditable;
 303         }
 304
 305         @Override
 306         public ISelection getSelection() {
 307                 return selection;
 308         }
 309 }