JabRef · lenhard · Mar 2, 2017 · Feb 24, 2017
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -17,6 +17,7 @@ We refer to [GitHub issues](https://github.com/JabRef/jabref/issues) by using `#
     - Redesigned group panel.
       - Number of matched entries is always shown.
       - The background color of the hit counter signals whether the group contains all/any of the entries selected in the main table. 
+      - Added a possibility to filter the groups panel [#1904](https://github.com/JabRef/jabref/issues/1904)
       - Removed edit mode.
     - Redesigned about dialog.
     - Redesigned key bindings dialog.

diff --git a/src/main/java/org/jabref/gui/groups/GroupNodeViewModel.java b/src/main/java/org/jabref/gui/groups/GroupNodeViewModel.java
@@ -27,6 +27,7 @@
 import org.jabref.model.groups.AllEntriesGroup;
 import org.jabref.model.groups.AutomaticGroup;
 import org.jabref.model.groups.GroupTreeNode;
+import org.jabref.model.strings.StringUtil;
 
 import com.google.common.eventbus.Subscribe;
 import org.fxmisc.easybind.EasyBind;
@@ -136,13 +137,8 @@ public boolean equals(Object o) {
 
         GroupNodeViewModel that = (GroupNodeViewModel) o;
 
-        if (isRoot != that.isRoot) return false;
-        if (!displayName.equals(that.displayName)) return false;
-        if (!iconCode.equals(that.iconCode)) return false;
-        if (!children.equals(that.children)) return false;
-        if (!databaseContext.equals(that.databaseContext)) return false;
         if (!groupNode.equals(that.groupNode)) return false;
-        return hits.getValue().equals(that.hits.getValue());
+        return true;
     }
 
     @Override
@@ -160,14 +156,7 @@ public String toString() {
 
     @Override
     public int hashCode() {
-        int result = displayName.hashCode();
-        result = 31 * result + (isRoot ? 1 : 0);
-        result = 31 * result + iconCode.hashCode();
-        result = 31 * result + children.hashCode();
-        result = 31 * result + databaseContext.hashCode();
-        result = 31 * result + groupNode.hashCode();
-        result = 31 * result + hits.hashCode();
-        return result;
+        return groupNode.hashCode();
     }
 
     public String getIconCode() {
@@ -207,4 +196,8 @@ public GroupTreeNode addSubgroup(AbstractGroup subgroup) {
     void toggleExpansion() {
         expandedProperty().set(!expandedProperty().get());
     }
+
+    boolean isMatchedBy(String searchString) {
+        return StringUtil.isBlank(searchString) || getDisplayName().contains(searchString);
+    }
 }
diff --git a/src/main/java/org/jabref/gui/groups/GroupTree.css b/src/main/java/org/jabref/gui/groups/GroupTree.css
@@ -107,7 +107,7 @@
     -fx-translate-x: -5px;
 }
 
-#buttonBarBottom {
+#barBottom {
     -fx-background-color: #dadad8;
     -fx-border-color: dimgray;
     -fx-border-width: 1 0 0 0;

diff --git a/src/main/java/org/jabref/gui/groups/GroupTree.fxml b/src/main/java/org/jabref/gui/groups/GroupTree.fxml
@@ -6,6 +6,8 @@
 <?import javafx.scene.control.TreeTableColumn?>
 <?import javafx.scene.control.TreeTableView?>
 <?import javafx.scene.layout.BorderPane?>
+<?import javafx.scene.layout.HBox?>
+<?import org.controlsfx.control.textfield.CustomTextField?>
 <?import org.controlsfx.glyphfont.Glyph?>
 <BorderPane xmlns:fx="http://javafx.com/fxml/1" prefHeight="600.0" prefWidth="150.0" styleClass="groupsPane"
             xmlns="http://javafx.com/javafx/8.0.112" fx:controller="org.jabref.gui.groups.GroupTreeController">
@@ -24,18 +26,21 @@
         </TreeTableView>
     </center>
     <bottom>
-        <ButtonBar fx:id="buttonBarBottom">
-            <buttons>
-                <Button fx:id="newGroupButton" onAction="#addNewGroup" styleClass="flatButton"
-                        ButtonBar.buttonData="LEFT">
-                    <graphic>
-                        <Glyph fontFamily="FontAwesome" icon="PLUS"/>
-                    </graphic>
-                    <tooltip>
-                        <Tooltip text="%New group"/>
-                    </tooltip>
-                </Button>
-            </buttons>
-        </ButtonBar>
+        <HBox fx:id="barBottom" alignment="CENTER">
+            <ButtonBar fx:id="buttonBarBottom">
+                <buttons>
+                    <Button fx:id="newGroupButton" onAction="#addNewGroup" styleClass="flatButton"
+                            ButtonBar.buttonData="LEFT">
+                        <graphic>
+                            <Glyph fontFamily="FontAwesome" icon="PLUS"/>
+                        </graphic>
+                        <tooltip>
+                            <Tooltip text="%New group"/>
+                        </tooltip>
+                    </Button>
+                </buttons>
+            </ButtonBar>
+            <CustomTextField fx:id="searchField" promptText="Filter groups"/>
+        </HBox>
     </bottom>
 </BorderPane>
diff --git a/src/main/java/org/jabref/gui/groups/GroupTreeController.java b/src/main/java/org/jabref/gui/groups/GroupTreeController.java
@@ -1,14 +1,19 @@
 package org.jabref.gui.groups;
 
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+
 import javax.inject.Inject;
 
+import javafx.beans.property.ObjectProperty;
 import javafx.css.PseudoClass;
 import javafx.event.ActionEvent;
 import javafx.fxml.FXML;
 import javafx.scene.control.ContextMenu;
 import javafx.scene.control.Control;
 import javafx.scene.control.MenuItem;
 import javafx.scene.control.SelectionModel;
+import javafx.scene.control.TextField;
 import javafx.scene.control.TreeItem;
 import javafx.scene.control.TreeTableColumn;
 import javafx.scene.control.TreeTableRow;
@@ -24,14 +29,21 @@
 import org.jabref.gui.util.ViewModelTreeTableCellFactory;
 import org.jabref.logic.l10n.Localization;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.controlsfx.control.textfield.CustomTextField;
+import org.controlsfx.control.textfield.TextFields;
 import org.fxmisc.easybind.EasyBind;
 
 public class GroupTreeController extends AbstractController<GroupTreeViewModel> {
 
+    private static final Log LOGGER = LogFactory.getLog(GroupTreeController.class);
+
     @FXML private TreeTableView<GroupNodeViewModel> groupTree;
     @FXML private TreeTableColumn<GroupNodeViewModel,GroupNodeViewModel> mainColumn;
     @FXML private TreeTableColumn<GroupNodeViewModel,GroupNodeViewModel> numberColumn;
     @FXML private TreeTableColumn<GroupNodeViewModel,GroupNodeViewModel> disclosureNodeColumn;
+    @FXML private CustomTextField searchField;
 
     @Inject private StateManager stateManager;
     @Inject private DialogService dialogService;
@@ -41,15 +53,23 @@ public void initialize() {
         viewModel = new GroupTreeViewModel(stateManager, dialogService);
 
         // Set-up bindings
-        groupTree.rootProperty().bind(
-                EasyBind.map(viewModel.rootGroupProperty(),
-                        group -> new RecursiveTreeItem<>(group, GroupNodeViewModel::getChildren, GroupNodeViewModel::expandedProperty))
-        );
         viewModel.selectedGroupProperty().bind(
                 EasyBind.monadic(groupTree.selectionModelProperty())
                         .flatMap(SelectionModel::selectedItemProperty)
                         .selectProperty(TreeItem::valueProperty)
         );
+        viewModel.filterTextProperty().bind(searchField.textProperty());
+        searchField.textProperty().addListener((observable, oldValue, newValue) -> {
+        });
+
+        groupTree.rootProperty().bind(
+                EasyBind.map(viewModel.rootGroupProperty(),
+                        group -> new RecursiveTreeItem<>(
+                                group,
+                                GroupNodeViewModel::getChildren,
+                                GroupNodeViewModel::expandedProperty,
+                                viewModel.filterPredicateProperty()))
+        );
 
         // Icon and group name
         mainColumn.setCellValueFactory(cellData -> cellData.getValue().valueProperty());
@@ -122,6 +142,9 @@ public void initialize() {
 
             return row;
         });
+
+        // Filter text field
+        setupClearButtonField(searchField);
     }
 
     private ContextMenu createContextMenuForGroup(GroupNodeViewModel group) {
@@ -137,4 +160,17 @@ private ContextMenu createContextMenuForGroup(GroupNodeViewModel group) {
     public void addNewGroup(ActionEvent actionEvent) {
         viewModel.addNewGroupToRoot();
     }
+
+    /**
+     * Workaround taken from https://bitbucket.org/controlsfx/controlsfx/issues/330/making-textfieldssetupclearbuttonfield
+     */
+    private void setupClearButtonField(CustomTextField customTextField) {
+        try {
+            Method m = TextFields.class.getDeclaredMethod("setupClearButtonField", TextField.class, ObjectProperty.class);
+            m.setAccessible(true);
+            m.invoke(null, customTextField, customTextField.rightProperty());
+        } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException ex) {
+            LOGGER.error("Failed to decorate text field with clear button", ex);
+        }
+    }
 }
diff --git a/src/main/java/org/jabref/gui/groups/GroupTreeViewModel.java b/src/main/java/org/jabref/gui/groups/GroupTreeViewModel.java
@@ -2,9 +2,13 @@
 
 import java.util.Objects;
 import java.util.Optional;
+import java.util.function.Predicate;
 
+import javafx.beans.binding.Bindings;
 import javafx.beans.property.ObjectProperty;
 import javafx.beans.property.SimpleObjectProperty;
+import javafx.beans.property.SimpleStringProperty;
+import javafx.beans.property.StringProperty;
 
 import org.jabref.gui.AbstractViewModel;
 import org.jabref.gui.DialogService;
@@ -21,18 +25,23 @@ public class GroupTreeViewModel extends AbstractViewModel {
     private final ObjectProperty<GroupNodeViewModel> selectedGroup = new SimpleObjectProperty<>();
     private final StateManager stateManager;
     private final DialogService dialogService;
+    private final ObjectProperty<Predicate<GroupNodeViewModel>> filterPredicate = new SimpleObjectProperty<>();
+    private final StringProperty filterText = new SimpleStringProperty();
     private Optional<BibDatabaseContext> currentDatabase;
 
     public GroupTreeViewModel(StateManager stateManager, DialogService dialogService) {
         this.stateManager = Objects.requireNonNull(stateManager);
         this.dialogService = Objects.requireNonNull(dialogService);
 
-        // Init
-        onActiveDatabaseChanged(stateManager.activeDatabaseProperty().getValue());
-
         // Register listener
         stateManager.activeDatabaseProperty().addListener((observable, oldValue, newValue) -> onActiveDatabaseChanged(newValue));
         selectedGroup.addListener((observable, oldValue, newValue) -> onSelectedGroupChanged(newValue));
+
+        // Set-up bindings
+        filterPredicate.bind(Bindings.createObjectBinding(() -> group -> group.isMatchedBy(filterText.get()), filterText));
+
+        // Init
+        onActiveDatabaseChanged(stateManager.activeDatabaseProperty().getValue());
     }
 
     public ObjectProperty<GroupNodeViewModel> rootGroupProperty() {
@@ -43,6 +52,14 @@ public ObjectProperty<GroupNodeViewModel> selectedGroupProperty() {
         return selectedGroup;
     }
 
+    public ObjectProperty<Predicate<GroupNodeViewModel>> filterPredicateProperty() {
+        return filterPredicate;
+    }
+
+    public StringProperty filterTextProperty() {
+        return filterText;
+    }
+
     /**
      * Gets invoked if the user selects a different group.
      * We need to notify the {@link StateManager} about this change so that the main table gets updated.

diff --git a/src/main/java/org/jabref/gui/util/RecursiveTreeItem.java b/src/main/java/org/jabref/gui/util/RecursiveTreeItem.java
@@ -1,11 +1,17 @@
 package org.jabref.gui.util;
 
 import java.util.List;
+import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
+import javafx.beans.binding.Bindings;
 import javafx.beans.property.BooleanProperty;
+import javafx.beans.property.ObjectProperty;
+import javafx.beans.property.SimpleObjectProperty;
+import javafx.beans.value.ObservableValue;
 import javafx.collections.ListChangeListener;
 import javafx.collections.ObservableList;
+import javafx.collections.transformation.FilteredList;
 import javafx.scene.Node;
 import javafx.scene.control.TreeItem;
 import javafx.util.Callback;
@@ -17,20 +23,29 @@ public class RecursiveTreeItem<T> extends TreeItem<T> {
 
     private final Callback<T, BooleanProperty> expandedProperty;
     private Callback<T, ObservableList<T>> childrenFactory;
+    private ObjectProperty<Predicate<T>> filter = new SimpleObjectProperty<>();
+    private FilteredList<T> children;
 
     public RecursiveTreeItem(final T value, Callback<T, ObservableList<T>> func) {
-        this(value, func, null);
+        this(value, func, null, null);
     }
 
-    public RecursiveTreeItem(final T value, Callback<T, ObservableList<T>> func, Callback<T, BooleanProperty> expandedProperty) {
-        this(value, (Node) null, func, expandedProperty);
+    public RecursiveTreeItem(final T value, Callback<T, ObservableList<T>> func, Callback<T, BooleanProperty> expandedProperty, ObservableValue<Predicate<T>> filter) {
+        this(value, null, func, expandedProperty, filter);
     }
 
-    public RecursiveTreeItem(final T value, Node graphic, Callback<T, ObservableList<T>> func, Callback<T, BooleanProperty> expandedProperty) {
+    public RecursiveTreeItem(final T value, Callback<T, ObservableList<T>> func, ObservableValue<Predicate<T>> filter) {
+        this(value, null, func, null, filter);
+    }
+
+    private RecursiveTreeItem(final T value, Node graphic, Callback<T, ObservableList<T>> func, Callback<T, BooleanProperty> expandedProperty, ObservableValue<Predicate<T>> filter) {
         super(value, graphic);
 
         this.childrenFactory = func;
         this.expandedProperty = expandedProperty;
+        if (filter != null) {
+            this.filter.bind(filter);
+        }
 
         if(value != null) {
             addChildrenListener(value);
@@ -40,7 +55,7 @@ public RecursiveTreeItem(final T value, Node graphic, Callback<T, ObservableList
         valueProperty().addListener((obs, oldValue, newValue)->{
             if(newValue != null){
                 addChildrenListener(newValue);
-                bindExpandedProperty(value, expandedProperty);
+                bindExpandedProperty(newValue, expandedProperty);
             }
         });
     }
@@ -52,17 +67,14 @@ private void bindExpandedProperty(T value, Callback<T, BooleanProperty> expanded
     }
 
     private void addChildrenListener(T value){
-        final ObservableList<T> children = childrenFactory.call(value);
+        children = new FilteredList<>(childrenFactory.call(value));
+        children.predicateProperty().bind(Bindings.createObjectBinding(() -> this::showNode, filter));
 
-        children.forEach(child -> RecursiveTreeItem.this.getChildren().add(new RecursiveTreeItem<>(child, getGraphic(), childrenFactory, expandedProperty)));
+        children.forEach(this::addAsChild);
 
         children.addListener((ListChangeListener<T>) change -> {
             while(change.next()){
 
-                if(change.wasAdded()){
-                    change.getAddedSubList().forEach(t -> RecursiveTreeItem.this.getChildren().add(new RecursiveTreeItem<>(t, getGraphic(), childrenFactory, expandedProperty)));
-                }
-
                 if(change.wasRemoved()){
                     change.getRemoved().forEach(t->{
                         final List<TreeItem<T>> itemsToRemove = RecursiveTreeItem.this.getChildren().stream().filter(treeItem -> treeItem.getValue().equals(t)).collect(Collectors.toList());
@@ -71,7 +83,28 @@ private void addChildrenListener(T value){
                     });
                 }
 
+                if (change.wasAdded()) {
+                    change.getAddedSubList().forEach(this::addAsChild);
+                }
             }
         });
     }
+
+    private boolean addAsChild(T child) {
+        return RecursiveTreeItem.this.getChildren().add(new RecursiveTreeItem<>(child, getGraphic(), childrenFactory, expandedProperty, filter));
+    }
+
+    private boolean showNode(T t) {
+        if (filter.get() == null) {
+            return true;
+        }
+
+        if (filter.get().test(t)) {
+            // Node is directly matched -> so show it
+            return true;
+        }
+
+        // Are there children (or children of children...) that are matched? If yes we also need to show this node
+        return childrenFactory.call(t).stream().anyMatch(this::showNode);
+    }
 }