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  1. JDK
  2. JDK-8090221

FilteredList in ComboBox that gets new Predicate set causes Selection to change internally but not visually

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    Details

    • Type: Bug
    • Status: Open
    • Priority: P3
    • Resolution: Unresolved
    • Affects Version/s: 8u40, 9
    • Fix Version/s: tbd
    • Component/s: javafx
    • Environment:

      Microsoft Windows [Version 6.1.7601]

      java version "1.8.0_40-ea"
      Java(TM) SE Runtime Environment (build 1.8.0_40-ea-b15)
      Java HotSpot(TM) 64-Bit Server VM (build 25.40-b18, mixed mode)

      Description

      ISSUE:

      Creating a ComboBox that has a sorted and filtered list and then changing the Predicate on the FilteredList causes "getSelectedItem" on the ComboBox to return null, but the visually selected item in the ComboBox itself remains the same.

      If the selected item returns null, it would also be expected that the visual item is "nothing".

      HOW TO REPRODUCE:

      Run the test code below. Just press the button a few times and the error should present itself.

      TEST CODE:

      import java.util.Comparator;
      import java.util.function.Predicate;

      import javafx.application.Application;
      import javafx.beans.property.SimpleStringProperty;
      import javafx.beans.property.StringProperty;
      import javafx.collections.FXCollections;
      import javafx.collections.ObservableList;
      import javafx.collections.transformation.FilteredList;
      import javafx.collections.transformation.SortedList;
      import javafx.geometry.Insets;
      import javafx.scene.Scene;
      import javafx.scene.control.Button;
      import javafx.scene.control.ComboBox;
      import javafx.scene.control.Label;
      import javafx.scene.control.ListCell;
      import javafx.scene.control.ListView;
      import javafx.scene.control.TextArea;
      import javafx.scene.layout.VBox;
      import javafx.stage.Stage;
      import javafx.util.Callback;

      public class ComboFilteredListPredicateNotUpdatingSelectedItem extends Application {

      private FilteredList<ComboItem> _filteredList;

      public static void main(String[] args) {
      launch(args);
      }

      @Override
      public void start(Stage primaryStage) throws Exception {
      final ComboBox<ComboItem> combo = new ComboBox<>();

      ObservableList<ComboItem> items = FXCollections.observableArrayList();
      for (int i = 0; i < 10; i++) {
      items.add(new ComboItem("Hello " + i));
      }

      SortedList<ComboItem> sorted = items.sorted(new Comparator<ComboItem>() {
      @Override
      public int compare(ComboItem o1, ComboItem o2) {
      return o1.getText().compareTo(o2.getText());
      }
      });

      _filteredList = sorted.filtered(getPredicate());
      combo.setItems(_filteredList);
      combo.getSelectionModel().select(0);

      combo.setButtonCell(new ListCell<ComboItem>() {
      @Override
      protected void updateItem(ComboItem item, boolean empty) {
      super.updateItem(item, empty);
      setText(empty ? null : item.getText());
      }
      });
      combo.setCellFactory(new Callback<ListView<ComboItem>, ListCell<ComboItem>>() {
      @Override
      public ListCell<ComboItem> call(ListView<ComboItem> param) {
      return new ListCell<ComboItem>() {
      @Override
      protected void updateItem(ComboItem item, boolean empty) {
      super.updateItem(item, empty);
      setText(empty ? null : item.getText());
      }
      };
      }
      });

      TextArea out = new TextArea();

      combo.getSelectionModel().selectedItemProperty().addListener((prop, ov, nv) -> {
      out.appendText("Selected item property changed to " + nv + "\n");
      });

      Label howTo = new Label("Press 'Change Filter' a few times, watch how the combo item you picked stays selected, but the printout says it's null");
      howTo.setWrapText(true);

      Button b = new Button("Change Filter");
      b.setOnAction(e -> {
      out.appendText("Selected Item Before: " + combo.getSelectionModel().getSelectedItem() + "\n");
      _filteredList.setPredicate(getPredicate());
      out.appendText("Selected Item After: " + combo.getSelectionModel().getSelectedItem() + "\n");
      });

      VBox content = new VBox(10);
      content.setPadding(new Insets(20));
      content.getChildren().addAll(howTo, combo, b, out);
      Scene scene = new Scene(content, 600, 500);
      primaryStage.setScene(scene);
      primaryStage.show();
      }

      private Predicate<ComboItem> getPredicate() {
      return new Predicate<ComboItem>() {
      @Override
      public boolean test(ComboItem t) {
      return true;
      }
      };
      }

      public class ComboItem {
      private StringProperty _textProperty;

      public StringProperty textProperty() {
      if (_textProperty == null) {
      _textProperty = new SimpleStringProperty();
      }

      return _textProperty;
      }

      public void setText(String text) {
      textProperty().set(text);
      }

      public String getText() {
      return textProperty().get();
      }

      public ComboItem(String text) {
      setText(text);
      }

      @Override
      public String toString() {
      return "ComboItem [_textProperty=" + getText() + "]";
      }

      }

      }

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            Assignee:
            aghaisas Ajit Ghaisas
            Reporter:
            ecrumhornjfx Emil Crumhorn (Inactive)
            Votes:
            1 Vote for this issue
            Watchers:
            13 Start watching this issue

              Dates

              Created:
              Updated:
              Imported: