編輯javafx TableView單元格中的數字

Question

我正在為朋友制作一個相當復雜的桌面應用程序，作為學習Java的一種方式，特別是Java 8和JavaFX。 該應用程序將具有大量表格，並且像高度特定的電子表格一樣工作，並且與估算運輸成本有關。 到目前為止，我已經學會了使用Scene Builder，並使用css結構，並設計了自己的類來表示表中的數據。 這是我的Vessel類的簡化版本：

    import javafx.beans.property.*; 

public class Vessel
{
    private  StringProperty name;
    private  FloatProperty deadWeight;

    public Vessel(){
        this.name = new SimpleStringProperty("ENTER SHIP NAME");
        this.deadWeight = new SimpleFloatProperty(0);
    }

    public Vessel(String name, float deadWeight){
        this.name = new SimpleStringProperty(name);
    }

    public void setName(String name){this.name.set(name);}
    public void setDeadWeight(float deadWeight){this.deadWeight.set(deadWeight);}   

    public String getName(){
        if ( !(name.get().equals("")) || (name.get()==null) || (name.get().trim().equals("ENTER SHIP NAME")) )
            return name.get();
      return null;
    }

    public float getDeadWeight(){return  deadWeight.get();} 

    public StringProperty nameProperty() { return name;}
    public FloatProperty deadWeightProperty() { return deadWeight;}

    public void clear(){
            this.name.set("ENTER SHIP NAME");
            this.deadWeight.set(0);
    }
}

我需要直接編輯TableView中的單元格，它們是浮點數或字符串。 我可以使用字符串，從我在這個網站上收集的信息，但無法弄清楚如何做浮動。

這是控制器文件VesselController.java：

    import javafx.fxml.FXML;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.layout.AnchorPane; 
import javafx.beans.property.SimpleFloatProperty;
import javafx.beans.value.*;
import javafx.scene.control.TreeTableColumn.CellDataFeatures;

 public class VesselController {  

    @FXML  private AnchorPane root;
    @FXML  private TableView<Vessel> vesselTable;
    @FXML  private TableColumn<Vessel, String> vesselTableNameCol;
    @FXML  private TableColumn<Vessel, Number> vesselTableDWTCol;

    // Reference to the main application.
    private MyMain mainApp;

    //The constructor, it is called before the initialize() method.
    public VesselController() {}

    //Initializes the controller class. This method is automatically called after the fxml file has been loaded.
    @FXML
    private void initialize() {
        // Initialize the vessel table with the columns.
      vesselTableNameCol.setCellValueFactory(cellData -> cellData.getValue().nameProperty());
        vesselTableNameCol.setCellFactory(column -> EditCell.createStringEditCell());

      vesselTableDWTCol.setCellValueFactory(cellData -> cellData.getValue().deadWeightProperty());

        // vesselTableDWTCol.setCellFactory(column -> EditCell.createStringEditCell()); //not working, as it needs to reurn a SimpleFloatProperty type
        //so tried this, but don't have a clear idea of what I'm doing
        vesselTableDWTCol.setCellValueFactory(new Callback<CellDataFeatures<Vessel, Number>, ObservableValue<Number>>() {
                @Override
                public ObservableValue<Number> call(CellDataFeatures<Vessel, Number> p) {
                return new SimpleFloatProperty(p.getValue().deadWeightProprerty());
                } 
            });

    }

    //Is called by the main application to give a reference back to itself.
    public void setMainApp(MyMain mainApp) {
      this.mainApp = mainApp;
      vesselTable.setItems(mainApp.getVesselData());   // Add observable list data to the table
        vesselTable.setColumnResizePolicy(TableView.CONSTRAINED_RESIZE_POLICY);
       vesselTable.setEditable(true);
    }
}

這是顯示錯誤的類，我不知道為什么 - 我需要實現回調嗎？ 如果是這樣，我該怎么做？ 我從這篇文章中收集了一些代碼，試圖讓它與Numbers一起使用。 我從James_D的存儲庫下載的EditCell類。

以下是運行它的MyMain.java：

    import java.io.*;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Scene; 
import javafx.scene.layout.*;
import javafx.stage.Stage;
import javafx.collections.ObservableList;
import javafx.collections.FXCollections;

public class MyMain extends Application {
    private Stage primaryStage;

    //The data as an observable list of Persons.
    private ObservableList<Vessel> vesselData = FXCollections.observableArrayList();

    //Constructor
   public MyMain() {          // Add some sample data
         vesselData.add(new Vessel()); //init empty row
    }

    // Returns the data as an observable list of Vessels (in this case a single row) 
    public ObservableList<Vessel> getVesselData() { return vesselData; }

    // Shows the vessel overview inside the root layout.
    @Override
    public void start(Stage primaryStage) { 
        this.primaryStage = primaryStage;
        this.primaryStage.setTitle("My Vessel");      
        show();
     }

    //Initializes the root layout. 
    public void show() {
        try {          
            FXMLLoader loader = new FXMLLoader(); // Load root layout from fxml file.
            loader.setLocation(MyMain.class.getResource("MyUI.fxml"));
            AnchorPane root = (AnchorPane) loader.load();

                // Give the controller access to the main app.
                VesselController controller = loader.getController();
                controller.setMainApp(this);

            // Show the scene containing the root layout.
            Scene scene = new Scene(root);
            primaryStage.setScene(scene);
            primaryStage.show();
        } catch (IOException e) { e.printStackTrace();}
    } 

    // Returns the main stage.
    public Stage getPrimaryStage() {
        return primaryStage;
    }

    public static void main(String[] args) { 
        Application.launch(MyMain.class, (java.lang.String[])null);
    }
}

我很確定我需要修改EditCell類，並且我試圖創建我自己的“NumberConverter”而沒有任何運氣 - 我不完全理解泛化，但我很確定我需要去那個路徑由於應用程序的總體最終復雜性。 為這么長的帖子道歉。

如果有人能提供一些很棒的指導。

Answer 1

我認為你不需要使用EditCell類。 或者，您可以使用TextFieldTableCell類。 您需要為vesselTableDWTCol列調用setcellfactory(...)方法（您可以使用vesselTableNameCol列執行相同的vesselTableNameCol ）。

使用以下代碼段：

// this line allow you to edit  cells in `vesselTableNameCol` column 
    vesselTableNameCol.setCellFactory(TextFieldTableCell.forTableColumn());
// this line allow you to edit  cells in `vesselTableDWTCol` column
    vesselTableDWTCol.setCellFactory(TextFieldTableCell.forTableColumn(new FloatStringConverter()));