我添加了一个cusom组件,用户可以在其中键入TextField
,然后弹出TableView
,然后用户可以在该表中查找项目。
我对KeyEvent
的standard TextField
有疑问,例如Ctrl + A或Home。弹出带有TableView
的窗格后,这些按键事件不再起作用。我检查了TextField
是否失去了焦点,但没有失去焦点,并且如果我设置了EventFilter
以查看正在发生的情况,则表明这些事件已触发,但对UI没有影响。甚至弹出窗口的setHideOnEscape
都不起作用。
这是验证它的简单代码:
fxml:
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.TextField?>
<?import javafx.scene.layout.AnchorPane?>
<AnchorPane xmlns="http://javafx.com/javafx"
xmlns:fx="http://javafx.com/fxml"
fx:controller="textField.Controller">
<TextField fx:id="textField" prefWidth="400"/>
</AnchorPane>
控制器:
public class Controller implements Initializable {
@FXML
private TextField textField;
@Override
public void initialize(URL location, ResourceBundle resources) {
Popup popUp = new Popup();
TableView<Object> table = new TableView<>();
table.prefWidthProperty().bind(textField.widthProperty());
popUp.getContent().add(table);
popUp.setHideOnEscape(true);
popUp.setAutoHide(true);
// To see if the KeyEvent is triggered
textField.addEventFilter(KeyEvent.ANY, System.out::println);
textField.setOnKeyTyped(event -> {
if(!popUp.isShowing()){
popUp.show(
textField.getScene().getWindow(),
textField.getScene().getWindow().getX()
+ textField.localToScene(0, 0).getX()
+ textField.getScene().getX(),
textField.getScene().getWindow().getY()
+ textField.localToScene(0, 0).getY()
+ textField.getScene().getY()
+ textField.getHeight() - 1);
}
});
}
}
和主要:
public class Main extends Application {
public void start(Stage primaryStage) throws Exception {
FXMLLoader loader = new FXMLLoader(getClass().getResource("View.fxml"));
AnchorPane pane = loader.load();
primaryStage.setScene(new Scene(pane, 800, 600));
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
这是控制台输出
KeyEvent [source = TextField[id=textField, styleClass=text-input text-field], target = TextField[id=textField, styleClass=text-input text-field], eventType = KEY_PRESSED, consumed = false, character = , text = a, code = A]
KeyEvent [source = TextField[id=textField, styleClass=text-input text-field], target = TextField[id=textField, styleClass=text-input text-field], eventType = KEY_TYPED, consumed = false, character = a, text = , code = UNDEFINED]
KeyEvent [source = TextField[id=textField, styleClass=text-input text-field], target = TextField[id=textField, styleClass=text-input text-field], eventType = KEY_RELEASED, consumed = false, character = , text = a, code = A]
KeyEvent [source = TextField[id=textField, styleClass=text-input text-field], target = TextField[id=textField, styleClass=text-input text-field], eventType = KEY_PRESSED, consumed = false, character = , text = , code = CONTROL, controlDown, shortcutDown]
KeyEvent [source = TextField[id=textField, styleClass=text-input text-field], target = TextField[id=textField, styleClass=text-input text-field], eventType = KEY_TYPED, consumed = false, character = , text = , code = UNDEFINED, controlDown, shortcutDown]
KeyEvent [source = TextField[id=textField, styleClass=text-input text-field], target = TextField[id=textField, styleClass=text-input text-field], eventType = KEY_RELEASED, consumed = false, character = , text = a, code = A, controlDown, shortcutDown]
KeyEvent [source = TextField[id=textField, styleClass=text-input text-field], target = TextField[id=textField, styleClass=text-input text-field], eventType = KEY_RELEASED, consumed = false, character = , text = , code = CONTROL]
任何想法,为什么那些事件即使不是事实也要消耗掉?
textField不对某些/所有“标准功能键”做出反应的原因是,它们的KEY_PRESSED类型永远不会到达它-它们被重定向到弹出窗口中的表,并且大多数/所有它们都被表使用。 >
天真的第一近似值是将表的focusTraversable属性设置为false:这有效地防止了将所有键传递给它。现实世界中的需求可能不太简单,因为其中一些需求应该到达表,而其他需求应该冒充到textField。
这可以通过自定义EventDispatcher(在表上)来实现,该事件检查器检查所有keyEvent并确定要传递/不传递给表的原始调度程序。一个代码片段,其中拦截器是用于决策的谓词(为方便起见,最后有完整的工作示例):
private BasicEventDispatcher original; private Predicate<Event> interceptor; @Override public Event dispatchEvent(Event event, EventDispatchChain tail) { if (!interceptor.test(event)) { event = original.dispatchCapturingEvent(event); if (event.isConsumed()) { return null; } } event = tail.dispatchEvent(event); if (event != null && !interceptor.test(event)) { event = original.dispatchBubblingEvent(event); if (event.isConsumed()) { return null; } } return event; }
用法:如果是f.i.我们希望将LEFT和RIGT冒泡到该textField,而所有其他字段应由表正常处理
List<KeyCode> toIntercept = List.of(KeyCode.LEFT, KeyCode.RIGHT); Predicate<Event> interceptor = e -> { if (e instanceof KeyEvent) { return toIntercept.contains(((KeyEvent) e).getCode()); } return false; }; table.setEventDispatcher(new InterceptingEventDispatcher( (BasicEventDispatcher) table.getEventDispatcher(), interceptor));
一个完整的例子:
public class ViewPopupApplication extends Application {
public static class InterceptingEventDispatcher implements EventDispatcher {
private BasicEventDispatcher original;
private Predicate<Event> interceptor;
public InterceptingEventDispatcher(BasicEventDispatcher original, Predicate<Event> interceptor) {
this.original = original;
this.interceptor = interceptor;
}
@Override
public Event dispatchEvent(Event event, EventDispatchChain tail) {
if (!interceptor.test(event)) {
event = original.dispatchCapturingEvent(event);
if (event.isConsumed()) {
return null;
}
}
event = tail.dispatchEvent(event);
if (event != null && !interceptor.test(event)) {
event = original.dispatchBubblingEvent(event);
if (event.isConsumed()) {
return null;
}
}
return event;
}
}
private Parent createContent() {
TableView<Locale> table = new TableView<>(FXCollections.observableArrayList(Locale.getAvailableLocales()));
// just to see that right/left are intercepted while up/down are handled
table.getSelectionModel().setCellSelectionEnabled(true);
TableColumn<Locale, String> country = new TableColumn<>("Country");
country.setCellValueFactory(new PropertyValueFactory<>("displayCountry"));
TableColumn<Locale, String> language = new TableColumn<>("Language");
language.setCellValueFactory(new PropertyValueFactory<>("displayLanguage"));
table.getColumns().addAll(country, language);
// disables default focus traversal
// table.setFocusTraversable(false);
// decide which keys to intercept
List<KeyCode> toIntercept = List.of(KeyCode.LEFT, KeyCode.RIGHT);
Predicate<Event> interceptor = e -> {
if (e instanceof KeyEvent) {
return toIntercept.contains(((KeyEvent) e).getCode());
}
return false;
};
table.setEventDispatcher(new InterceptingEventDispatcher(
(BasicEventDispatcher) table.getEventDispatcher(), interceptor));
TextField textField = new TextField("something to show");
textField.setPrefColumnCount(20);
textField.setText("something to see");
table.prefWidthProperty().bind(textField.widthProperty());
Popup popUp = new Popup();
popUp.getContent().add(table);
textField.setOnKeyTyped(event -> {
if(!popUp.isShowing()){
popUp.show(
textField.getScene().getWindow(),
textField.getScene().getWindow().getX()
+ textField.localToScene(0, 0).getX()
+ textField.getScene().getX(),
textField.getScene().getWindow().getY()
+ textField.localToScene(0, 0).getY()
+ textField.getScene().getY()
+ textField.getHeight() - 1);
}
});
BorderPane content = new BorderPane(textField);
return content;
}
@Override
public void start(Stage stage) throws Exception {
stage.setScene(new Scene(createContent()));
stage.show();
}
public static void main(String[] args) {
launch(args);
}
}