按鈕不改變本地原始變量與JavaFx

Question

我是新來的JavaFx，我試圖創建一個簡單的確認框，確定用戶是否真的要退出或沒有類。它有一個函數返回一個布爾值，表示如果用戶點擊「是」或「否」：

public class ConfirmBoxController implements IView { 

    public javafx.scene.control.Button yes_BTN; 
    public javafx.scene.control.Button no_BTN; 

    private volatile boolean answer; 

    // Constructors..// 

    public boolean confirm(){ 
     try{ 
      stage = new Stage(); 
      FXMLLoader fxmlLoader = new FXMLLoader(); 
      Parent root = fxmlLoader.load(getClass().getResource("ConfirmBox.fxml").openStream()); 
      Scene scene = new Scene(root, 250, 140); 
      stage.setScene(scene); 
      stage.showAndWait(); 

      return answer; 
     } 
     catch(Exception E){ 
      E.printStackTrace(); 
      return true; 
     } 
    } 

    public void yes() { 
     this.answer = true; 
     Stage stage = (Stage) yes_BTN.getScene().getWindow(); 
     stage.close(); 
    } 

    public void no() { 
     this.answer = false; 
     Stage stage = (Stage) no_BTN.getScene().getWindow(); 
     stage.close(); 
    } 
} 

我試圖使「答案」揮發，而不是，但它並沒有改變任何東西。

Answer 1

你可以用JavaFX構建Dialog或Alert這裏這個功能是一個教程如何使用它們：http://code.makery.ch/blog/javafx-dialogs-official/

這就是你可能需要：

Alert alert = new Alert(AlertType.CONFIRMATION); 
alert.setTitle("Confirmation Dialog"); 
alert.setHeaderText("Look, a Confirmation Dialog"); 
alert.setContentText("Are you ok with this?"); 

Optional<ButtonType> result = alert.showAndWait(); 
if (result.get() == ButtonType.OK){ 
    // ... user chose OK 
} else { 
    // ... user chose CANCEL or closed the dialog 
} 

或者，如果你想有一個是/否警報，然後兩個ButtonType s

Alert yesNoAlert = new Alert(Alert.AlertType.CONFIRMATION); 
yesNoAlert.setTitle("Title"); 
yesNoAlert.setContentText("Content"); 
yesNoAlert.setHeaderText("Header"); 


ButtonType buttonYes = new ButtonType("Yes", ButtonBar.ButtonData.YES); 
ButtonType buttonNo = new ButtonType("No" , ButtonBar.ButtonData.NO); 

yesNoAlert.getButtonTypes().setAll(buttonYes,buttonNo); 

Optional<ButtonType> result = yesNoAlert.showAndWait(); 
if (result.get() == buttonYes){ 
    // ... 
} else { 
    // ... 
}