java - 如何在 JavaFx 中检测 tableview 项目计数调整大小？

Question

我正在尝试使用 FX Tableview 过滤和显示项目计数。

有一些按钮和txt字段用于列出特定数据 here is

文本输入:过滤

清除按钮:在此处输入代码默认值

本月按钮:获取本月值

数据选择器:用于获取任何一天的值

有一个显示表格项目大小的标签

public Label lblRecordSize;

我的问题； 我不想 lblRecordSize.settext() 在每个过滤操作下。 有没有tableview.onItemSizeChangeListener()等监听器

更新:

public class CenterDbController implements Initializable {

    public AnchorPane centerDbPanelPane;

    /** */
    public TextField txtSerialNo;
    public ComboBox<EModemModel> cbxModemModel;
    public Label lblRecordSize;
    public DatePicker dpStartDate;
    public DatePicker dpEndDate;
    public Button btnShow;
    public Button btnClear;

    /** */
    public TableView<RecordedTest> tblvRecords;
    public TableColumn colRecordId;
    public TableColumn colOfficeId;
    public TableColumn colCompany;
    public TableColumn colModemSerialNumber;
    public TableColumn colModemBrand;
    public TableColumn colModemModel;
    public TableColumn colSoftwareVersion;
    public TableColumn colAccessTest;
    public TableColumn colSoftwareTest;
    public TableColumn colDhcpTest;
    public TableColumn colWifiTest;
    public TableColumn colInternetTest;
    public TableColumn colResetTest;
    public TableColumn colTestResult;
    public TableColumn colSendStatus;
    public TableColumn colRecordDate;
    public TableColumn colTestDetails;

    /** */
    private IRecordedTestService recordedTestService;
    private FilteredList<RecordedTest> filteredList;

    @Override
    public void initialize(URL location, ResourceBundle resources) {

        initCellFactories();

        recordedTestService = UtilsForSpring.getSingleBeanOfType(IRecordedTestService.class);
        filteredList = new FilteredList<>(FXCollections.observableList(recordedTestService.getThisMonthRecords()), s -> true);
        tblvRecords.setItems(filteredList);
        lblRecordSize.textProperty().bind(Bindings.size(tblvRecords.getItems()).asString("%s"));
//        lblRecordSize.setText(filteredList.size() + "");

        filteredList.addListener(new ListChangeListener<RecordedTest>() {
            @Override
            public void onChanged(Change<? extends RecordedTest> c) {
//                lblRecordSize.setText(filteredList.size() + "");
            }
        });


        cbxModemModel.getItems().addAll(EModemModel.values());


    }


    private void initCellFactories() {

        colRecordId.setCellValueFactory(new PropertyValueFactory<RecordedTest, String>("recordId"));
        colOfficeId.setCellValueFactory(new PropertyValueFactory<>("officeId"));
        colCompany.setCellValueFactory(new PropertyValueFactory<>("company"));
        colModemSerialNumber.setCellValueFactory(new PropertyValueFactory<>("modemSerialNumber"));
        colModemBrand.setCellValueFactory(new PropertyValueFactory<>("modemBrand"));
        colModemModel.setCellValueFactory(new PropertyValueFactory<>("modemModel"));
        colSoftwareVersion.setCellValueFactory(new PropertyValueFactory<>("softwareVersion"));

        colAccessTest.setCellValueFactory(new PropertyValueFactory<>("accessTest"));
        colSoftwareTest.setCellValueFactory(new PropertyValueFactory<>("softwareTest"));
        colDhcpTest.setCellValueFactory(new PropertyValueFactory<>("dhcpTest"));
        colWifiTest.setCellValueFactory(new PropertyValueFactory<>("wifiTest"));
        colInternetTest.setCellValueFactory(new PropertyValueFactory<>("internetTest"));
        colResetTest.setCellValueFactory(new PropertyValueFactory<>("resetTest"));
        colTestResult.setCellValueFactory(new PropertyValueFactory<>("testResult"));
        colSendStatus.setCellValueFactory(new PropertyValueFactory<>("sendStatus"));

        colRecordDate.setCellValueFactory(new PropertyValueFactory<>("recordDate"));
        colTestDetails.setCellValueFactory(new PropertyValueFactory<>("testDetails"));

    }

    public void btnClearOnClickAction(ActionEvent e) {

        txtSerialNo.clear();
        cbxModemModel.getSelectionModel().clearSelection();
        dpEndDate.setValue(null);
        dpStartDate.setValue(null);

        filteredList = new FilteredList<>(FXCollections.observableList(recordedTestService.getThisMonthRecords()), s -> true);
        tblvRecords.setItems(filteredList);
//        lblRecordSize.setText(filteredList.size() + "");

    }

    public void btnShowOnClickAction(ActionEvent e) {

        if (dpStartDate.getValue() != null && dpEndDate != null) {
            filteredList = new FilteredList<>(FXCollections.observableList(recordedTestService.getBetweenRecords(dpStartDate.getValue(), dpEndDate.getValue())));
            tblvRecords.setItems(filteredList);
        }
    }


    public void tableOnSortListener() {


//        lblRecordSize.setText(tblvRecords.getItems().size() + "");
    }

    public void txtSerialNoOnKeyPress() {

        txtSerialNo.textProperty().addListener(observable -> {
            String filter = txtSerialNo.getText();
            if (filter == null || filter.length() == 0) {
                filteredList.setPredicate(s -> true);
            } else {
                filteredList.setPredicate(s -> s.getModemSerialNumber().contains(filter));
            }
        });
    }

    public void cbxModemModelOnValueChange() {

        String filter = cbxModemModel.getSelectionModel().getSelectedItem().toString();
        if (filter == null || filter.length() == 0) {
            filteredList.setPredicate(s -> true);
        } else {
            filteredList.setPredicate(s -> s.getModemModel().equalsIgnoreCase(filter));
        }
    }

}

Answer 1

Bindings class提供了一个 size 方法，允许您为 ObservableList 的大小创建绑定(bind)。假设您在每次过滤时修改现有列表并且不将其替换为新列表(例如使用 FilteredList)，您可以使用它来绑定(bind) Label 文本:

// after assigning the items
lblRecordSize.textProperty().bind(Bindings.size(tableview.getItems()).asString("Record count: %s"));

---

编辑

在您的代码中，您替换了项目列表。 items 未被替换的先决条件未给出...

您可以改为向 item 属性添加一个监听器，并且每次都重新绑定(bind) Label 文本

// before setting items the first time
tblvRecords.itemsProperty().addListener((observable, oldItems, newItems) -> 
                                           lblRecordSize.textProperty().bind(
                                                   Bindings.size(newItems).asString()));

但是，您也可以修改单个列表以包含源数据，而不是每次都重新创建列表:

private final ObservableList<RecordedTest> data = FXCollections.observableArrayList();
private final FilteredList<RecordedTest> filteredList = new FilteredList<>(data);

@Override
public void initialize(URL location, ResourceBundle resources) {

    initCellFactories();

    recordedTestService = UtilsForSpring.getSingleBeanOfType(IRecordedTestService.class);
    filteredList.setPredicate(null);
    data.setAll(recordedTestService.getThisMonthRecords());
    tblvRecords.setItems(filteredList);
    lblRecordSize.textProperty().bind(Bindings.size(filteredList).asString());
    ...
}

...

public void btnClearOnClickAction(ActionEvent e) {
    ...

    filteredList.setPredicate(null);
    data.setAll(recordedTestService.getThisMonthRecords()));
}