Feature: implement search filter in show preferences (#4759)

* Feature: implement search filter in show preferences

Add a search box in show preferences window to allow users to filter
preference options.

Resolves #1019

* Add Locale.ROOT when converting to lower case

* Fixed indentation for fxml

* Added Locale.ROOT when converting to lower case

* Using FilteredList to filter options on search

* set the count label text, which was accidently removed

* Moved checkbox to the top

* Bind count label to table size property

Author: CaptainDaVinci

src/main/java/org/jabref/gui/preferences/PreferencesFilterDialog.fxml

@@ -7,21 +7,30 @@
 <?import javafx.scene.control.Label?>
 <?import javafx.scene.control.TableColumn?>
 <?import javafx.scene.control.TableView?>
+<?import javafx.scene.control.TextField?>
 <?import javafx.scene.layout.BorderPane?>
 <?import javafx.scene.layout.HBox?>
+<?import javafx.scene.layout.VBox?>
 <DialogPane xmlns:fx="http://javafx.com/fxml/1" prefHeight="600.0" prefWidth="950.0"
             xmlns="http://javafx.com/javafx/8.0.121" fx:controller="org.jabref.gui.preferences.PreferencesFilterDialog">
 
     <content>
         <BorderPane>
             <bottom>
-                <HBox>
-                    <CheckBox fx:id="showOnlyDeviatingPreferenceOptions"
-                              text="%Show only preferences deviating from their default value"/>
-                    <HBox HBox.hgrow="ALWAYS"/>
+                <HBox alignment="BOTTOM_RIGHT">
                     <Label fx:id="count"/>
                 </HBox>
             </bottom>
+            <top>
+                <HBox spacing="20">
+                    <TextField fx:id="searchField" promptText="%Search"/>
+                    <VBox alignment="CENTER">
+                        <CheckBox fx:id="showOnlyDeviatingPreferenceOptions"
+                            text="%Show only preferences deviating from their default value" alignment="bottom_right"/>
+                    </VBox>
+                    <HBox HBox.hgrow="ALWAYS"/>
+                </HBox>
+            </top>
             <center>
                 <TableView fx:id="table">
                     <columns>

src/main/java/org/jabref/gui/preferences/PreferencesFilterDialog.java

@@ -1,16 +1,20 @@
 package org.jabref.gui.preferences;
 
+import java.util.Locale;
 import java.util.Objects;
 
+import javafx.beans.binding.Bindings;
 import javafx.beans.property.ReadOnlyObjectWrapper;
 import javafx.beans.property.ReadOnlyStringWrapper;
 import javafx.collections.FXCollections;
 import javafx.collections.ObservableList;
+import javafx.collections.transformation.FilteredList;
 import javafx.fxml.FXML;
 import javafx.scene.control.CheckBox;
 import javafx.scene.control.Label;
 import javafx.scene.control.TableColumn;
 import javafx.scene.control.TableView;
+import javafx.scene.control.TextField;
 
 import org.jabref.gui.util.BaseDialog;
 import org.jabref.logic.l10n.Localization;
@@ -22,6 +26,7 @@ public class PreferencesFilterDialog extends BaseDialog<Void> {
 
     private final JabRefPreferencesFilter preferencesFilter;
     private final ObservableList<JabRefPreferencesFilter.PreferenceOption> preferenceOptions;
+    private final FilteredList<JabRefPreferencesFilter.PreferenceOption> filteredOptions;
 
     @FXML private TableView<JabRefPreferencesFilter.PreferenceOption> table;
     @FXML private TableColumn<JabRefPreferencesFilter.PreferenceOption, JabRefPreferencesFilter.PreferenceType> columnType;
@@ -30,10 +35,12 @@ public class PreferencesFilterDialog extends BaseDialog<Void> {
     @FXML private TableColumn<JabRefPreferencesFilter.PreferenceOption, Object> columnDefaultValue;
     @FXML private CheckBox showOnlyDeviatingPreferenceOptions;
     @FXML private Label count;
+    @FXML private TextField searchField;
 
     public PreferencesFilterDialog(JabRefPreferencesFilter preferencesFilter) {
         this.preferencesFilter = Objects.requireNonNull(preferencesFilter);
         this.preferenceOptions = FXCollections.observableArrayList();
+        this.filteredOptions = new FilteredList<>(this.preferenceOptions);
 
         ViewLoader.view(this)
                   .load()
@@ -45,11 +52,20 @@ public PreferencesFilterDialog(JabRefPreferencesFilter preferencesFilter) {
     @FXML
     private void initialize() {
         showOnlyDeviatingPreferenceOptions.setOnAction(event -> updateModel());
+        filteredOptions.predicateProperty().bind(Bindings.createObjectBinding(() -> {
+            String searchText = searchField.getText();
+            if ((searchText == null) || searchText.isEmpty()) {
+                return null;
+            }
+            String lowerCaseSearchText = searchText.toLowerCase(Locale.ROOT);
+            return (option) -> option.getKey().toLowerCase(Locale.ROOT).contains(lowerCaseSearchText);
+        }, searchField.textProperty()));
         columnType.setCellValueFactory(data -> new ReadOnlyObjectWrapper<>(data.getValue().getType()));
         columnKey.setCellValueFactory(data -> new ReadOnlyStringWrapper(data.getValue().getKey()));
         columnValue.setCellValueFactory(data -> new ReadOnlyObjectWrapper<>(data.getValue().getValue()));
         columnDefaultValue.setCellValueFactory(data -> new ReadOnlyObjectWrapper<>(data.getValue().getDefaultValue().orElse("")));
-        table.setItems(preferenceOptions);
+        table.setItems(filteredOptions);
+        count.textProperty().bind(Bindings.size(table.getItems()).asString("(%d)"));
         updateModel();
     }
 
@@ -59,6 +75,6 @@ private void updateModel() {
         } else {
             preferenceOptions.setAll(preferencesFilter.getPreferenceOptions());
         }
-        count.setText(String.format("(%d)", preferenceOptions.size()));
     }
+
 }