JavaFx组合框valueProperty（）.addListener（新的ChangeListener<；String>；（）逐步重复

我正在JavaFX项目上使用ComboBox。当我使用valueProperty（）.addListener（new ChangeListener（））时， 它是随着每次单击而逐步重复的操作

这是我的控制器：

public class Controller  {

// some code 

@FXML
private ComboBox<String> FruitList;


int count = 1;

public void comboAction() {
        FruitList.valueProperty().addListener(new ChangeListener<String>() {
            @Override
            public void changed(ObservableValue<? extends String> observable, String oldValue, String newValue) {
                System.out.println("Selected value : " + newValue);
            }
        });
    //count number of select actions
    System.out.println("Selection number: " + count++);

    }
}

如果您查看以下内容：

ComboBox操作，每当ComboBox值 属性已更改

所以当你这样做的时候：

<ComboBox fx:id="FruitList" onAction="#comboAction" ...>

Selection number: 1

Selected value : Apple

Selection number: 2

Selected value : Pear

Selected value : Pear

Selection number: 3

Selected value : Orange

Selected value : Orange

Selected value : Orange

Selection number: 4

Selected value : Apple

Selected value : Apple

Selected value : Apple

Selected value : Apple

Selection number: 5 Selected value : Pear

Selected value : Pear

Selected value : Pear

Selected value : Pear

Selected value : Pear

Selected value : Pear

<ComboBox fx:id="FruitList" onAction="#comboAction" ...>

public void comboAction() {
    System.out.println("Selected value : " + FruitList.getValue());
}