我正在为我的桌面应用程序设计关闭窗口功能。列出了该功能的高级说明:
ConfirmBox
用户确认是否要保存。ConfirmBox
代码中,我有绑定ENTER键来保存东西,N键不保存东西,ESCAPE键关闭confirmBox。 一切正常。但是,如果我按照这个特殊的步骤顺序,会有一个小错误。 每当我使用加速器进入Exit menuItem (即METAKEY + E)和时,我按下3个键中的任意一个(ENTER,ESCAPE,N),confirmBox关闭但它再次弹出。
我想知道为什么只在这种非常特殊的情况下才会发生这种情况?
public class ConfirmBox {
// answer[0] determines the need to Save
// answer[1] determines whether to close the application or not
private static boolean[] answer = new boolean[]{false,false};
private static Stage window;
public static boolean[] displayWarning(String title, String message){
window = new Stage();
window.initModality(Modality.APPLICATION_MODAL);
window.setTitle(title);
window.setMinWidth(300);
Label label = new Label();
label.setText(message);
Button yesButton = new Button("Yes");
Button noButton = new Button("No");
// needToSave = true, close Application = true and close this confirmbox
yesButton.setOnAction(ey ->{
answer[0] = true;
answer[1] = true;
window.close();
});
// needToSave = false, close Application = true and close this confirmbox
noButton.setOnAction(en -> {
answer[0] = false;
answer[1] = true;
window.close();
});
// needToSave = false, close Application = false and close this confirmbox
window.setOnCloseRequest(e -> {
answer[0] = false;
answer[1] = false;
closeConfirmBox();
});
// key binding
window.addEventHandler(KeyEvent.KEY_PRESSED, e -> {
if ( e.getCode() == KeyCode.N){
noButton.fire();
e.consume();
}
});
// bind enter key to yesButton
window.addEventHandler(KeyEvent.KEY_PRESSED, ev -> {
if (ev.getCode() == KeyCode.ENTER ){
yesButton.fire();
ev.consume();
}
});
window.addEventFilter(KeyEvent.KEY_PRESSED, ev ->{
if(ev.getCode()==KeyCode.ESCAPE){
ev.consume();
answer[0] = false;
answer[1] = false;
closeConfirmBox();
}
});
VBox layout = new VBox(20);
layout.setPadding(new Insets(20,5,20,5));
HBox bottomLayout = new HBox(50);
bottomLayout.setPadding(new Insets(20,5,20,5));
bottomLayout.getChildren().addAll(yesButton,noButton);
bottomLayout.setAlignment(Pos.CENTER);
layout.getChildren().addAll(label,bottomLayout);
layout.setAlignment(Pos.CENTER);
Scene scene = new Scene(layout);
window.setScene(scene);
window.showAndWait();
return answer;
}
public static void closeConfirmBox(){
window.close();
}
}
在我的控制器类中,这就是我设计MenuItem menuItemExit
的方式。
menuItemExit.setOnAction(new EventHandler<ActionEvent>(){
@Override
public void handle(ActionEvent e){
//System.out.println("set stage" + primaryStage);
boolean[] answer;
boolean needToSave = false;
boolean closeApplication = false;
if(saved.get() == false){
answer = ConfirmBox.displayWarning("Warning", "Do you want to save your stuff?");
needToSave = answer[0];
closeApplication = answer[1];
}
if(needToSave == true){
menuItemSave.fire();
}
if(closeApplication== true){
Platform.runLater(new Runnable() {
public void run() {
close();
}
});
}
}
});
primaryStage.setOnCloseRequest(e -> {
e.consume();
menuItemExit.fire();
});
menuItemExit.setAccelerator(new KeyCodeCombination(KeyCode.E, KeyCombination.META_DOWN));
public void close(){
this.primaryStage.close();
}