Javafx：以编程方式关闭警报框（或任何对话框）

Question

我有一个 JavaFx 应用程序，我在其中显示一个警告框，使用：

alert = new Alert(AlertType.CONFIRMATION);
alert.setTitle("Title");
alert.setHeaderText("Some Text");
alert.setContentText("Choose your option.");
buttonTypeOne = new ButtonType("Yes");
buttonTypeCancel = new ButtonType("No", ButtonData.CANCEL_CLOSE);
alert.getButtonTypes().setAll(buttonTypeOne, buttonTypeCancel);
Optional<ButtonType> result = alert.showAndWait();

因为警报执行showAndWait，所以它会一直显示，直到用户按下“是”或“否”或“关闭”对话框。

问题：我需要从其他地方以编程方式关闭此对话框。详细说明一下，假设用户在 20 秒内没有选择任何选项，或者假设此警报框显示为某个刚刚结束的后台进程，现在我希望通过将 result 设置为来关闭此警报框是buttonTypeCancel，而不是用户按下任何按钮。 （就像 Swing 中的 dispose 方法）

我该怎么做？我尝试了 Event.fireevent (https://stackoverflow.com/a/22459308/3155986)，但我无法编写正确的关联事件。

提前致谢！

编辑：包括示例代码-

1. MainApp.java - 负责处理应用程序的 Java 类
2. Controller.java - 对应的控制器文件
3. Design.fxml - 通过 MainApp.java 加载并由 Controller.java 控制的应用程序的 FXML 文件

4. Compute.java - 另一个执行计算的 java 类。

   公共类计算{ 警报警报；

   public void function1{
     Platform.runLater(new Runnable(){
         public void run(){
         alert = new Alert(AlertType.CONFIRMATION);
         alert.setTitle("Title");
         alert.setHeaderText("Some Text");
         alert.setContentText("Choose your option.");
         buttonTypeOne = new ButtonType("Yes");
         buttonTypeCancel = new ButtonType("No", ButtonData.CANCEL_CLOSE);
         alert.getButtonTypes().setAll(buttonTypeOne, buttonTypeCancel);
   
         Optional<ButtonType> result = alert.showAndWait();
         if (result.get() == buttonTypeOne){
         // ... user chose "One"
         } else {
         // ... user chose CANCEL or closed the dialog
         }
   
         }
     });
   }
   
   public void function2{
    //......Does some long computation here 
    //.... If the computation finishes before the user chooses 'Yes' or 'No' on alert box
   //...Then close the alertbox here and execute the code corresponding to buttonTypeCancel
   
   
   //..I tried alert.close(); and alert.hide(); but doesn't work.
   }
   

   }

另外，是否有任何替代解决方案可以做到这一点？最初，我想保持Compute.java 中没有任何 javafx 代码，但不知道怎么做。

Answer 1

试试这个

public void function2 {
    Button cancelButton = ( Button ) alert.getDialogPane().lookupButton( buttonTypeCancel );
    cancelButton.fire();
}

或者更一般的

public void function2 {
    for ( ButtonType bt : alert.getDialogPane().getButtonTypes() )
    {
        if ( bt.getButtonData() == ButtonBar.ButtonData.CANCEL_CLOSE )
        {
            Button cancelButton = ( Button ) alert.getDialogPane().lookupButton( bt );
            cancelButton.fire();
            break;
        }
    }
}

---

完整示例：

@Override
public void start( final Stage primaryStage )
{
    Alert alert = new Alert( Alert.AlertType.CONFIRMATION );
    alert.setTitle( "Title" );
    alert.setHeaderText( "Some Text" );
    alert.setContentText( "Choose your option." );
    ButtonType buttonTypeOne = new ButtonType( "Yes" );
    alert.initModality( Modality.NONE );
    ButtonType buttonTypeCancel = new ButtonType( "No", ButtonBar.ButtonData.CANCEL_CLOSE );
    alert.getButtonTypes().setAll( buttonTypeOne, buttonTypeCancel );

    Button b = new Button( "close alert" );
    b.setOnAction(( ActionEvent event ) ->
    {
        for ( ButtonType bt : alert.getDialogPane().getButtonTypes() )
        {
            System.out.println( "bt = " + bt );
            if ( bt.getButtonData() == ButtonBar.ButtonData.CANCEL_CLOSE )
            {
                Button cancelButton = ( Button ) alert.getDialogPane().lookupButton( bt );
                cancelButton.fire();
                break;
            }
        }
    });

    final Scene scene = new Scene( new Group( b ), 400, 300 );
    primaryStage.setScene( scene );
    primaryStage.show();

    Optional<ButtonType> result = alert.showAndWait();
    if ( result.get() == buttonTypeOne )
    {
        System.out.println( "one " );
    }
    else if( result.get() == buttonTypeCancel )
    {
        System.out.println( "cancel " );
    }
}

Answer 2

您可以在警报或任何对话框中调用close() 方法。

这是一个等待 5 秒的简单示例，如果警报仍然显示，则将其关闭。

import javafx.application.Application;
import javafx.application.Platform;
import javafx.scene.control.Alert;
import javafx.scene.control.ButtonBar;
import javafx.scene.control.ButtonType;
import javafx.stage.Stage;

import java.util.Optional;

public class Main extends Application{

    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage primaryStage) throws Exception {
        Alert alert = new Alert(Alert.AlertType.CONFIRMATION);
        alert.setTitle("Title");
        alert.setHeaderText("Some Text");
        alert.setContentText("Choose your option.");
        ButtonType buttonTypeOne = new ButtonType("Yes");
        ButtonType buttonTypeCancel = new ButtonType("No", ButtonBar.ButtonData.CANCEL_CLOSE);
        alert.getButtonTypes().setAll(buttonTypeOne, buttonTypeCancel);

        Thread thread = new Thread(() -> {
            try {
                // Wait for 5 secs
                Thread.sleep(5000);
                if (alert.isShowing()) {
                    Platform.runLater(() -> alert.close());
                }
            } catch (Exception exp) {
                exp.printStackTrace();
            }
        });
        thread.setDaemon(true);
        thread.start();
        Optional<ButtonType> result = alert.showAndWait();
    }
}

Answer 3

在 2 秒内关闭打开的对话框。

dialog = new Dialog<>();
dialog.setTitle("It's a dialog!");
dialog.show();

    Thread newThread = new Thread(new Runnable() {
    @Override
        public void run() {
            try {
                Thread.sleep(2000);
            } catch (InterruptedException ex) {
                Thread.currentThread().interrupt();
            }

            Platform.runLater(new Runnable() {
                @Override
                public void run() {
                    dialog.close();
                }
                });
            }
    });
    newThread.start();