缩小父级时JavaFX TreeView没有刷新，显示“儿童文物”

Question

我有一个TreeView，在缩小父目录时，我仍然看到原始子节点。只存在作为“神器”，不是真的存在而且不可点击。这是导致问题的代码的一部分。我知道，因为当我评论它时，TreeView工作正常。

    selectionTreeView.setCellFactory(new Callback<TreeView<String>, TreeCell<String>>() {
    @Override
    public TreeCell<String> call(TreeView<String> paramP) {
        return new TreeCell<String>(){
            @Override
            protected void updateItem(String paramT, boolean paramBoolean) {
                super.updateItem(paramT, paramBoolean);
                if(!isEmpty()){
                    setGraphic(new Label(paramT));
                    final TreeCell<String> this$ = this;
                    this.setOnMouseClicked(new EventHandler<MouseEvent>() {
                    @Override
                    public void handle(MouseEvent event) {
                        if(event.getClickCount()==2){
                            // Getting the node value.
                            String nodeValue = this$.getItem();
                        }
                    }
                    });
                }
            }
        };
    }
    });

这允许我在双击时返回子项的值。不确定如何纠正问题。任何建议，任何帮助将不胜感激？如果它有帮助，请在下面包含完整的源代码。最后使用JDK 8u5。

package javafxapplication1;

import java.net.URL;
import java.sql.*;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ResourceBundle;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Label;
import javafx.scene.control.TreeCell;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.input.MouseEvent;
import javafx.util.Callback;

/**
*
* @author kevin_000
*/
public class FXMLDocumentController implements Initializable {

@FXML
private Label label;
@FXML TreeView selectionTreeView;

@FXML
private void handleButtonAction(ActionEvent event) {
    System.out.println("You clicked me!");
    label.setText("Hello World!");
}
//should delete item selected, does not work currently
@FXML
private void testRemoveTreeItem(ActionEvent event) {
        TreeItem<String> c = (TreeItem)selectionTreeView.getSelectionModel().getSelectedItem();
        boolean remove = c.getParent().getChildren().remove(c);
        System.out.println("Remove");
    }

@Override
public void initialize(URL url, ResourceBundle rb) {
    createTree();
    //Get Name of TreeViewCell Double Clicked
    selectionTreeView.setCellFactory(new Callback<TreeView<String>, TreeCell<String>>() {
    @Override
    public TreeCell<String> call(TreeView<String> paramP) {
        return new TreeCell<String>(){
            @Override
            protected void updateItem(String paramT, boolean paramBoolean) {
                super.updateItem(paramT, paramBoolean);
                if(!isEmpty()){
                    setGraphic(new Label(paramT));
                    final TreeCell<String> this$ = this;
                    this.setOnMouseClicked(new EventHandler<MouseEvent>() {
                    @Override
                    public void handle(MouseEvent event) {
                        if(event.getClickCount()==2){
                            // Getting the node value.
                            String nodeValue = this$.getItem();
                        }
                    }
                    });
                }
            }
        };
    }
    });
}

  public void createTree(String... rootItems) {
    //create root
    TreeItem<String> root = new TreeItem<>("Sales Analysis & Goal Is King");
    //root.setExpanded(true);
    //january
    TreeItem<String> itemJanuary = new TreeItem<>("January");
    itemJanuary.setExpanded(false);
    TreeItem<String> itemSalesAnalysisJanuary = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisJanuary.setExpanded(false);
    TreeItem<String> itemGoalIsKingJanuary = new TreeItem<>("Goal Is King");
    itemGoalIsKingJanuary.setExpanded(false);        
    //february
    TreeItem<String> itemFebruary = new TreeItem<>("February");
    itemFebruary.setExpanded(false);
    TreeItem<String> itemSalesAnalysisFebruary = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisFebruary.setExpanded(false);
    TreeItem<String> itemGoalIsKingFebruary = new TreeItem<>("Goal Is King");
    itemGoalIsKingFebruary.setExpanded(false);
    //march
    TreeItem<String> itemMarch = new TreeItem<>("March");
    itemMarch.setExpanded(false);
    TreeItem<String> itemSalesAnalysisMarch = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisMarch.setExpanded(false);
    TreeItem<String> itemGoalIsKingMarch = new TreeItem<>("Goal Is King");
    itemGoalIsKingMarch.setExpanded(false);
    //april
    TreeItem<String> itemApril = new TreeItem<>("April");
    itemApril.setExpanded(false);
    TreeItem<String> itemSalesAnalysisApril = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisApril.setExpanded(false);
    TreeItem<String> itemGoalIsKingApril = new TreeItem<>("Goal Is King");
    itemGoalIsKingApril.setExpanded(false);
    //may
    TreeItem<String> itemMay = new TreeItem<>("May");
    itemMay.setExpanded(false);
    TreeItem<String> itemSalesAnalysisMay = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisMay.setExpanded(false);
    TreeItem<String> itemGoalIsKingMay = new TreeItem<>("Goal Is King");
    itemGoalIsKingMay.setExpanded(false);
    //june
    TreeItem<String> itemJune = new TreeItem<>("June");
    itemJune.setExpanded(false);
    TreeItem<String> itemSalesAnalysisJune = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisJune.setExpanded(false);
    TreeItem<String> itemGoalIsKingJune = new TreeItem<>("Goal Is King");
    itemGoalIsKingJune.setExpanded(false);
    //july
    TreeItem<String> itemJuly = new TreeItem<>("July");
    itemJuly.setExpanded(false);
    TreeItem<String> itemSalesAnalysisJuly = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisJuly.setExpanded(false);
    TreeItem<String> itemGoalIsKingJuly = new TreeItem<>("Goal Is King");
    itemGoalIsKingJuly.setExpanded(false);        
    //august
    TreeItem<String> itemAugust = new TreeItem<>("August");
    itemAugust.setExpanded(false);
    TreeItem<String> itemSalesAnalysisAugust = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisAugust.setExpanded(false);
    TreeItem<String> itemGoalIsKingAugust = new TreeItem<>("Goal Is King");
    itemGoalIsKingAugust.setExpanded(false);        
    //september
    TreeItem<String> itemSeptember = new TreeItem<>("September");
    itemSeptember.setExpanded(false);
    TreeItem<String> itemSalesAnalysisSeptember = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisSeptember.setExpanded(false);
    TreeItem<String> itemGoalIsKingSeptember = new TreeItem<>("Goal Is King");
    itemGoalIsKingSeptember.setExpanded(false);        
    //october
    TreeItem<String> itemOctober = new TreeItem<>("October");
    itemOctober.setExpanded(false);
    TreeItem<String> itemSalesAnalysisOctober = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisOctober.setExpanded(false);
    TreeItem<String> itemGoalIsKingOctober = new TreeItem<>("Goal Is King");
    itemGoalIsKingOctober.setExpanded(false);        
    //november
    TreeItem<String> itemNovember = new TreeItem<>("November");
    itemNovember.setExpanded(false);
    TreeItem<String> itemSalesAnalysisNovember = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisNovember.setExpanded(false);
    TreeItem<String> itemGoalIsKingNovember = new TreeItem<>("Goal Is King");
    itemGoalIsKingNovember.setExpanded(false);        
    //december
    TreeItem<String> itemDecember = new TreeItem<>("December");
    itemDecember.setExpanded(false);
    TreeItem<String> itemSalesAnalysisDecember = new TreeItem<>("Sales Analysis");
    itemSalesAnalysisDecember.setExpanded(false);
    TreeItem<String> itemGoalIsKingDecember = new TreeItem<>("Goal Is King");
    itemGoalIsKingDecember.setExpanded(false);        

    //create stores, stores are children of SalesAnalsysis & GoalIsKing Trees
    try (Connection connection = DriverManager.getConnection(
            "jdbc:derby://localhost:1527/FJH_Stores_&_Employees","kevinkabatra","ew4pkd8d");
        Statement statement = connection.createStatement();) {
        ResultSet rs = statement.executeQuery("select LOCATION from STORES");
        while (rs.next()){
            //january
            itemSalesAnalysisJanuary.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis January"));
            itemGoalIsKingJanuary.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King January"));
            //february
            itemSalesAnalysisFebruary.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis February"));
            itemGoalIsKingFebruary.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King February"));
            //march
            itemSalesAnalysisMarch.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis March"));
            itemGoalIsKingMarch.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King March"));
            //april
            itemSalesAnalysisApril.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis April"));
            itemGoalIsKingApril.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King April"));
            //may
            itemSalesAnalysisMay.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis May"));
            itemGoalIsKingMay.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King May"));
            //june
            itemSalesAnalysisJune.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis June"));
            itemGoalIsKingJune.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King June"));
            //july
            itemSalesAnalysisJuly.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis July"));
            itemGoalIsKingJuly.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King July"));
            //august
            itemSalesAnalysisAugust.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis August"));
            itemGoalIsKingAugust.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King August"));
            //september
            itemSalesAnalysisSeptember.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis September"));
            itemGoalIsKingSeptember.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King September"));
            //october
            itemSalesAnalysisOctober.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis October"));
            itemGoalIsKingOctober.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King October"));
            //november
            itemSalesAnalysisNovember.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis November"));
            itemGoalIsKingNovember.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King November"));
            //december
            itemSalesAnalysisDecember.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Sales Analsysis December"));
            itemGoalIsKingDecember.getChildren().add(new 
                TreeItem<>(rs.getString("LOCATION")+" Goal Is King December"));
        }
    } catch (SQLException ex) {
        System.err.print("Exception: ");
        System.err.println(ex.getMessage());
    }
    //SalesAnalysis and GoalIsKing are children of each month,
    //months are children of root
    itemJanuary.getChildren().addAll(itemSalesAnalysisJanuary,itemGoalIsKingJanuary);
    itemFebruary.getChildren().addAll(itemSalesAnalysisFebruary,itemGoalIsKingFebruary);
    itemMarch.getChildren().addAll(itemSalesAnalysisMarch,itemGoalIsKingMarch);
    itemApril.getChildren().addAll(itemSalesAnalysisApril,itemGoalIsKingApril);
    itemMay.getChildren().addAll(itemSalesAnalysisMay,itemGoalIsKingMay);
    itemJune.getChildren().addAll(itemSalesAnalysisJune,itemGoalIsKingJune);
    itemJuly.getChildren().addAll(itemSalesAnalysisJuly,itemGoalIsKingJuly);
    itemAugust.getChildren().addAll(itemSalesAnalysisAugust,itemGoalIsKingAugust);
    itemSeptember.getChildren().addAll(itemSalesAnalysisSeptember,itemGoalIsKingSeptember);
    itemOctober.getChildren().addAll(itemSalesAnalysisOctober,itemGoalIsKingOctober);
    itemNovember.getChildren().addAll(itemSalesAnalysisNovember,itemGoalIsKingNovember);
    itemDecember.getChildren().addAll(itemSalesAnalysisDecember,itemGoalIsKingDecember);
    root.getChildren().addAll(itemJanuary,itemFebruary,itemMarch,
            itemApril,itemMay,itemJune,itemJuly,itemAugust,itemSeptember,
            itemOctober,itemNovember,itemDecember);
    selectionTreeView.setRoot(root);
}
}

Answer 1

错误在你的updateItem方法中 - 当empty参数为true时你不会调用setGraphic（null）。

我应该注意，在这种情况下使用setGraphic是不正确的 - 当您可以使用paramT字符串调用setText时，您将传入Label。

此外，考虑到调用它的频率，我不会注意到你的updateItem方法正在做更多的工作。当item和empty参数更改为TreeCell的构造函数时（通过使用匿名构造函数），您应该移动与更新单元格无关的所有内容。这包括创建EventHandler - 只需要在构造函数中设置。