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Javafx tableview反射不起作用

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我试图用模拟数据填充JavaFx TableView列，但我不断收到反射错误，即使我认为我正在遵循Bean约定：

// Data model

class SensorTableEntry {
    SensorTableEntry(Integer id, String man, String type, String addr) {
        this.id = new SimpleIntegerProperty(id);
        this.manufacturer = new SimpleStringProperty(man);
        this.type = new SimpleStringProperty(type);
        this.btAddress = new SimpleStringProperty(addr);
    }

    private IntegerProperty id;
    public Integer getId() { return idProperty().get(); }
    public void setId(Integer value) { idProperty().set(value); }
    public IntegerProperty idProperty() { return id; } 

    private StringProperty manufacturer;
    public void setManufacturer(String value) { manufacturerProperty().set(value); }
    public String getManufacturer() { return manufacturerProperty().get(); }
    public StringProperty manufacturerProperty() { return manufacturer; }

    private StringProperty type;
    public void setType(String value) { typeProperty().set(value); }
    public String getType() { return typeProperty().get(); }
    public StringProperty typeProperty() { return type; } 

    private StringProperty btAddress;
    public void setBtAddress(String value) { btAddressProperty().set(value); }
    public String getBtAddress() { return btAddressProperty().get(); }
    public StringProperty btAddressProperty() { return btAddress; } 
}

// More code before this...


// Actual table inside the controller

ObservableList<SensorTableEntry> sensorEntries = FXCollections.observableArrayList(
    new SensorTableEntry(1, "manufacturer", "type", "00:00:00:00:00:00")
);   

TableView<SensorTableEntry> table = new TableView<SensorTableEntry>();

TableColumn<SensorTableEntry,Integer> idCol = new TableColumn<SensorTableEntry,Integer>("ID");
idCol.setCellValueFactory(new PropertyValueFactory<SensorTableEntry,Integer>("id"));

TableColumn<SensorTableEntry,String> manufacturerCol = new TableColumn<SensorTableEntry,String>("Manufacturer");
manufacturerCol.setCellValueFactory(new PropertyValueFactory<SensorTableEntry,String>("manufacturer"));

TableColumn<SensorTableEntry,String> typeCol = new TableColumn<SensorTableEntry,String>("Type");
typeCol.setCellValueFactory(new PropertyValueFactory<SensorTableEntry,String>("type"));

TableColumn<SensorTableEntry,String> btAddressCol = new TableColumn<SensorTableEntry,String>("Bluetooth Address");
btAddressCol.setCellValueFactory(new PropertyValueFactory<SensorTableEntry,String>("btAddress"));

table.setItems(sensorEntries);
table.getColumns().addAll(
    idCol,
    manufacturerCol,
    typeCol,
    btAddressCol
);

pane.getChildren().add(table);

我检查过类似问题的其他答案，例如：

Javafx PropertyValueFactory not populating Tableview

JavaFx TableView not filling all required columns

Javafx tableview not showing data in all columns

但无论我检查多少，我似乎都没有找到我的命名出错的地方 . 我错过了什么吗？

我得到的例外是：

线程“JavaFX Application Thread”中的异常java.lang.RuntimeException：java.lang.IllegalAccessException：类sun.reflect.misc.Trampoline无法访问com.Sun.javafx.property中带有修饰符“public”的SensorTableEntry类的成员.PropertyReference.getProperty（PropertyReference.java:200）

java javafx

2 回答

  • 1

    您的属性必须完全可访问，以便他们的getter和他们的所有者类 must both be public .

    So simply replace this:

    class SensorTableEntry {

    With this:

    public class SensorTableEntry {
    回复于
  • 4

    由于您在模型中使用JavaFX属性，因此可以使用回调的实际实现（为简洁起见使用lambda表达式）并完全避免反射 . 请注意 IntegerProperty 实现 Property<Number> ，而不是 Property<Integer> ，因此您需要修复类型（请参阅JavaFX Properties in TableView）：

    TableColumn<SensorTableEntry,Number> idCol = new TableColumn<SensorTableEntry,Number>("ID");
idCol.setCellValueFactory(cellData -> cellData.getValue().idProperty());

TableColumn<SensorTableEntry,String> manufacturerCol = new TableColumn<SensorTableEntry,String>("Manufacturer");
manufacturerCol.setCellValueFactory(cellData -> cellData.getValue().manufacturerProperty());

TableColumn<SensorTableEntry,String> typeCol = new TableColumn<SensorTableEntry,String>("Type");
typeCol.setCellValueFactory(cellData -> cellData.getValue().typeProperty());

TableColumn<SensorTableEntry,String> btAddressCol = new TableColumn<SensorTableEntry,String>("Bluetooth Address");
btAddressCol.setCellValueFactory(cellData -> cellData.getValue().btAddressProperty());

    这通常是一种更好的方法：编译器将检查属性是否存在且类型是否正确，并且由于您不依赖于反射来评估单元格值，因此性能会更好（可能可以忽略不计，但仍然...... ） .

    另外一个：在JavaFX属性模式中，原始包装器属性的方法应该使用基本类型，而不是对象包装器类型，即：

    class SensorTableEntry {
    SensorTableEntry(int id, String man, String type, String addr) {
        this.id = new SimpleIntegerProperty(id);
        this.manufacturer = new SimpleStringProperty(man);
        this.type = new SimpleStringProperty(type);
        this.btAddress = new SimpleStringProperty(addr);
    }

    private IntegerProperty id;
    public int getId() { return idProperty().get(); }
    public void setId(int value) { idProperty().set(value); }
    public IntegerProperty idProperty() { return id; } 

    // existing code...
}
    回复于

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