JavaFX微调器工作不正确。Spinner.valueProperty().addListener更改了两次
我不明白为什么,如果微调器调用ChangeListener两次。我怎样才能做到只打一次电话 Controller.javaJavaFX微调器工作不正确。Spinner.valueProperty().addListener更改了两次,java,javafx,javafx-8,spinner,Java,Javafx,Javafx 8,Spinner,我不明白为什么,如果微调器调用ChangeListener两次。我怎样才能做到只打一次电话 Controller.java public class Controller { @FXML Spinner<Double> spinner; @FXML public void initialize(){ spinner.setValueFactory(new SpinnerValueFactory.DoubleSpinnerValueFactory(0,350,60,1));
public class Controller {
@FXML
Spinner<Double> spinner;
@FXML
public void initialize(){
spinner.setValueFactory(new SpinnerValueFactory.DoubleSpinnerValueFactory(0,350,60,1));
spinner.valueProperty().addListener(new ChangeListener<Double>() {
@Override
public void changed(ObservableValue<? extends Double> observable, Double oldValue, Double newValue) {
System.out.println("Old Value" + oldValue + "New Value" + newValue);
}
});
}}
public class Main extends Application {
@Override
public void start(Stage primaryStage) throws Exception{
Parent root = FXMLLoader.load(getClass().getResource("sample.fxml"));
primaryStage.setTitle("Hello World");
primaryStage.setScene(new Scene(root, 300, 275));
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}}
Out:
Old Value 60.0 New Value 780.0
Old Value 780.0 New Value 350.0
这是因为
工厂:
spinner.setValueFactory(new SpinnerValueFactory.DoubleSpinnerValueFactory(0,350,60,1));
微调器的最大值为350。输入780:该值将更改为此值,然后由于最大值,它将更改回350
更新:
默认情况下,按下Enter键时,提交微调器编辑器中的值
为了避免自动绑定,您可以尝试覆盖默认提交逻辑:
spinner.getEditor().setOnAction(e -> {
String text = spinner.getEditor().getText();
SpinnerValueFactory<Double> valueFactory = spinner.getValueFactory();
if (valueFactory != null) {
StringConverter<Double> converter = valueFactory.getConverter();
if (converter != null) {
try{
Double value = converter.fromString(text);
if (value >= minValue && value <= maxValue)
valueFactory.setValue(value);
else
valueFactory.setValue(Math.max(Math.min(maxValue, value), minValue));
// This ensures that if the value us e.g. 350, then 450 entered, the text
// is updated to 350 again (rather than ramaining 450)
spinner.getEditor().setText(converter.toString(valueFactory.getValue()));
} catch(NumberFormatException nfe){
spinner.getEditor().setText(converter.toString(valueFactory.getValue()));
}
}
}
e.consume();
});
注意:
Old Value 60.0 New Value 780.0
Old Value 780.0 New Value 350.0
也可以从SpinnerValueFactory
中检索最小值和最大值-不幸的是,不是以完全干净的方式,而是通过一些铸造:
spinner.getEditor().setOnAction(e -> {
SpinnerValueFactory.DoubleSpinnerValueFactory valueFactory = (SpinnerValueFactory.DoubleSpinnerValueFactory) spinner.getValueFactory();
if (valueFactory != null) {
StringConverter<Double> converter = valueFactory.getConverter();
if (converter != null) {
try {
valueFactory.setValue(Math.max(Math.min(valueFactory.getMax(),
converter.fromString(spinner.getEditor().getText())), valueFactory.getMin()));
spinner.getEditor().setText(converter.toString(valueFactory.getValue()));
} catch(NumberFormatException nfe){
spinner.getEditor().setText(converter.toString(valueFactory.getValue()));
}
}
}
e.consume();
});
当它被调用两次时,您输入什么值?大于350?是的,例如,我输入了780是的,但是我如何才能只使一个调用方法public void changed()?另一个选项是在编辑器上设置TextFormatter
,并否决(或修改)超出范围的更改。@James\u D是的,这绝对正确。我只是不想创建tl;答:)
spinner.setValueFactory(new SpinnerValueFactory.DoubleSpinnerValueFactory(0, 350, 60, 1));