javaFX: ListView 选择模型内的单选按钮

Question

我需要 ListView 内的 RadioButtons 所以我找到了这个答案:

javaFX:listview with Radio Button

但问题是 ListView 中选定的单元格和选定的 RadioButton 未绑定(bind)。如果单击列表中的单元格，我想自动选择相应的 RadioButton。

所以我的问题是如何绑定(bind)这两个？

更新:因此，我设法做到这一点的唯一方法类似于@Sedrick Jefferson 的答案，但没有在 RadioButton 前面添加 StackPane 。我将 RadioButtons 名称RadioButtons 列表添加到 ToggleGroup 并将监听器添加到 selectedToggleProperty:当选择新的 RadioButton 时，我选择相应的ListView 中的行

    import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.ListCell;
import javafx.scene.control.ListView;
import javafx.scene.control.RadioButton;
import javafx.scene.control.ToggleGroup;
import javafx.scene.layout.Pane;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;

public class RadioButtonListView extends Application
{

    public static final ObservableList<RadioButton> namesRadioButtons
            = FXCollections.observableArrayList();
    private ToggleGroup group = new ToggleGroup();

    @Override
    public void start(Stage primaryStage)
    {
        primaryStage.setTitle("List View Sample");

        final ListView<RadioButton> listView = new ListView();
        listView.setPrefSize(200, 250);
        listView.setEditable(true);

        String[] names =
        {
            "Adam", "Alex", "Alfred", "Albert",
            "Brenda", "Connie", "Derek", "Donny",
            "Lynne", "Myrtle", "Rose", "Rudolph",
            "Tony", "Trudy", "Williams", "Zach"
        };

        for (String name : names)
        {
            namesRadioButtons.add(new RadioButton(name));
        }
        group.getToggles().addAll(namesRadioButtons);
        listView.setItems(namesRadioButtons);
        group.selectedToggleProperty().addListener((obs, oldSel, newSel) -> {
            listView.getSelectionModel().select((RadioButton) newSel);
            listView.getFocusModel().focus(listView.getSelectionModel().getSelectedIndex());
        });
        listView.setCellFactory(param -> new RadioListCell());
        listView.getSelectionModel().selectedItemProperty().addListener((obs, oldSel, newSel) ->
        {
            if (newSel != null)
            {
                RadioButton tempRadioButton = (RadioButton) newSel;
                tempRadioButton.setSelected(true);
            }
            if (oldSel != null)
            {
                RadioButton tempRadioButton = (RadioButton) oldSel;
                tempRadioButton.setSelected(false);
            }
        });

        StackPane root = new StackPane();
        root.getChildren().add(listView);
        primaryStage.setScene(new Scene(root, 200, 250));
        primaryStage.show();
    }

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

    private class RadioListCell extends ListCell<RadioButton>
    {

        @Override
        public void updateItem(RadioButton obj, boolean empty)
        {
            super.updateItem(obj, empty);
            if (empty)
            {
                setText(null);
                setGraphic(null);
            }
            else
            {
                setGraphic(obj);
            }
        }

    }
}

问题:有没有更好的解决方案？

Answer 1

重复一遍:将控件添加为数据项不是解决方案!

相反，请根据需要使用具有控件的自定义单元格，并配置项目/列表/选择的状态，就像 QA cited by the OP 中一样。 。唯一缺少的部分是反向同步(从 radio 状态到列表选择):要实现这一点，请在单元中安装一个监听器。

类似(修改后的示例):

public class RadioButtonListView extends Application {

    public static final ObservableList names =
            FXCollections.observableArrayList();
    private ToggleGroup group = new ToggleGroup();

    @Override
    public void start(Stage primaryStage) {
        primaryStage.setTitle("List View Sample");

        final ListView listView = new ListView();
        listView.setPrefSize(200, 250);
        listView.setEditable(true);

        names.addAll(
                "Adam", "Alex", "Alfred", "Albert",
                "Brenda", "Connie", "Derek", "Donny",
                "Lynne", "Myrtle", "Rose", "Rudolph",
                "Tony", "Trudy", "Williams", "Zach"
        );

        listView.setItems(names);
        listView.setCellFactory(param -> new RadioListCell());

        StackPane root = new StackPane();
        root.getChildren().add(listView);
        primaryStage.setScene(new Scene(root, 200, 250));
        primaryStage.show();
    }

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

    private class RadioListCell extends ListCell<String> {

        RadioButton radioButton;
        ChangeListener<Boolean> radioListener = (src, ov, nv) -> radioChanged(nv);
        WeakChangeListener<Boolean> weakRadioListener = new WeakChangeListener(radioListener);

        public RadioListCell() {
            radioButton = new RadioButton();
            radioButton.selectedProperty().addListener(weakRadioListener);
            radioButton.setFocusTraversable(false);
            // let it span the complete width of the list
            // needed in fx8 to update selection state
            radioButton.setMaxWidth(Double.MAX_VALUE);
        }

        protected void radioChanged(boolean selected) {
            if (selected && getListView() != null && !isEmpty() && getIndex() >= 0) {
                getListView().getSelectionModel().select(getIndex());
            }
        }

        @Override
        public void updateItem(String obj, boolean empty) {
            super.updateItem(obj, empty);
            if (empty) {
                setText(null);
                setGraphic(null);
                radioButton.setToggleGroup(null);
            } else {
                radioButton.setText(obj);
                radioButton.setToggleGroup(group);
                radioButton.setSelected(isSelected());
                setGraphic(radioButton);
            }
        }
    }
}

<小时/>

更新:

该示例在 fx9 中运行良好，但在 fx8 中出现问题:

• 当单击单选按钮外部(行尾部空白中的某个位置)时，所选单选按钮并不总是更新。这可以通过强制单选按钮拉伸(stretch)到列表的整个宽度来解决。

• 当 listView 的选择更改时， radio 的选定状态并不总是更新。这可以通过在单元格的选定属性中安装监听器并更新该监听器中的 radio 来处理。

• 当小区被重新使用时， radio 的选定状态不会可靠地更新。这需要进一步挖掘...