org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/repository/RepositoryTreeNodeLabelProvider.java

   1 /*******************************************************************************
   2  * Copyright (c) 2010, 2018 SAP AG and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Eclipse Public License 2.0
   5  * which accompanies this distribution, and is available at
   6  * https://www.eclipse.org/legal/epl-2.0/
   7  *
   8  * SPDX-License-Identifier: EPL-2.0
   9  *
  10  * Contributors:
  11  *    Mathias Kinzler (SAP AG) - initial implementation
  12  *    Chris Aniszczyk <caniszczyk@gmail.com> - added styled label support
  13  *    Thomas Wolf <thomas.wolf@paranor.ch> - bug 536814: completely refactored
  14  *******************************************************************************/
  15 package org.eclipse.egit.ui.internal.repository;
  16
  17 import java.util.WeakHashMap;
  18
  19 import org.eclipse.egit.ui.internal.GitLabels;
  20 import org.eclipse.egit.ui.internal.repository.tree.AdditionalRefNode;
  21 import org.eclipse.egit.ui.internal.repository.tree.RepositoryNode;
  22 import org.eclipse.egit.ui.internal.repository.tree.WorkingDirNode;
  23 import org.eclipse.jface.viewers.DecoratingStyledCellLabelProvider;
  24 import org.eclipse.jface.viewers.DelegatingStyledCellLabelProvider.IStyledLabelProvider;
  25 import org.eclipse.jface.viewers.ILabelProvider;
  26 import org.eclipse.jface.viewers.StyledString;
  27 import org.eclipse.jgit.lib.Ref;
  28 import org.eclipse.jgit.lib.Repository;
  29 import org.eclipse.ui.PlatformUI;
  30 import org.eclipse.ui.model.WorkbenchLabelProvider;
  31
  32 /**
  33  * A decorating label provider for repository tree nodes.
  34  */
  35 public class RepositoryTreeNodeLabelProvider
  36                 extends DecoratingStyledCellLabelProvider
  37                 implements ILabelProvider, IStyledLabelProvider {
  38
  39         private final WorkbenchLabelProvider labelProvider;
  40
  41         /**
  42          * Keeps the last label. If the label we originally get is undecorated, we
  43          * return this last decorated label instead to prevent flickering. When the
  44          * asynchronous lightweight decorator then has computed the decoration, the
  45          * label will be updated. Note that this works only because our
  46          * RepositoryTreeNodeDecorator always decorates! (If there's no decoration,
  47          * it appends a single blank to ensure the decorated label is different from
  48          * the undecorated one.)
  49          * <p>
  50          * For images, there is no such work-around, and thus we need to do the
  51          * image decorations in the label provider (in the
  52          * RepositoryTreeNodeWorkbenchAdapter in our case) in the UI thread.
  53          */
  54         private final WeakHashMap<Object, StyledString> previousDecoratedLabels = new WeakHashMap<>();
  55
  56         /**
  57          * Creates a new {@link RepositoryTreeNodeLabelProvider}.
  58          */
  59         public RepositoryTreeNodeLabelProvider() {
  60                 this(new WorkbenchLabelProvider());
  61         }
  62
  63         private RepositoryTreeNodeLabelProvider(
  64                         WorkbenchLabelProvider labelProvider) {
  65                 super(labelProvider, PlatformUI.getWorkbench()
  66                                 .getDecoratorManager().getLabelDecorator(), null);
  67                 this.labelProvider = labelProvider;
  68         }
  69
  70         @Override
  71         public void dispose() {
  72                 super.dispose();
  73                 previousDecoratedLabels.clear();
  74         }
  75
  76         @Override
  77         public StyledString getStyledText(Object element) {
  78                 StyledString decoratedLabel = super.getStyledText(element);
  79                 String decoratedValue = decoratedLabel.getString();
  80                 String simpleValue = labelProvider.getText(element);
  81                 if (decoratedValue.equals(simpleValue)) {
  82                         // Decoration not available yet... but may be shortly. Try to
  83                         // prevent flickering by returning the previous decorated label, if
  84                         // any.
  85                         StyledString previousLabel = previousDecoratedLabels.get(element);
  86                         if (previousLabel != null) {
  87                                 return previousLabel;
  88                         }
  89                 } else if (decoratedValue.trim().equals(simpleValue)) {
  90                         // No decoration...
  91                         decoratedLabel = labelProvider.getStyledText(element);
  92                 }
  93                 if (element instanceof RepositoryNode) {
  94                         Repository repository = ((RepositoryNode) element).getRepository();
  95                         if (repository != null) {
  96                                 decoratedLabel.append(" - ", StyledString.QUALIFIER_STYLER) //$NON-NLS-1$
  97                                                 .append(repository.getDirectory().getAbsolutePath(),
  98                                                                 StyledString.QUALIFIER_STYLER);
  99                         }
 100                 } else if (element instanceof WorkingDirNode) {
 101                         Repository repository = ((WorkingDirNode) element).getRepository();
 102                         if (repository != null) {
 103                                 decoratedLabel.append(" - ", StyledString.QUALIFIER_STYLER) //$NON-NLS-1$
 104                                                 .append(repository.getWorkTree().getAbsolutePath(),
 105                                                                 StyledString.QUALIFIER_STYLER);
 106                         }
 107                 }
 108                 previousDecoratedLabels.put(element, decoratedLabel);
 109                 return decoratedLabel;
 110         }
 111
 112         @Override
 113         public String getText(Object element) {
 114                 return labelProvider.getText(element);
 115         }
 116
 117         @Override
 118         public String getToolTipText(Object element) {
 119                 if (element instanceof AdditionalRefNode) {
 120                         AdditionalRefNode additionalRefNode = (AdditionalRefNode) element;
 121                         Ref ref = additionalRefNode.getObject();
 122                         return GitLabels.getRefDescription(ref);
 123                 }
 124                 return null;
 125         }
 126 }