java - 如何在显示之前设置 JavaFX 警报对话框位置？

Question

我想在显示后将警告对话框位置设置在右下角。

代码如下:

package alert;

import javafx.application.Application;
import javafx.geometry.Rectangle2D;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Alert;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.stage.Screen;
import javafx.stage.Stage;

public class MainAlert extends Application {

    @Override
    public void start(Stage stage) throws Exception {

        Scene scene = new Scene(createContent());
        stage.setScene(scene);
        stage.setMaximized(true);
        stage.show();
    }

    private Parent createContent() {

        StackPane stackPane = new StackPane();

        Alert alert = new Alert(Alert.AlertType.ERROR);
        alert.setTitle("Error Dialog");
        alert.setHeaderText("Something went wrong");
        alert.setContentText("There is an error!");

        Button alertButton = new Button("Alert test");
        alertButton.setOnAction(event -> {
            Rectangle2D bounds = Screen.getPrimary().getVisualBounds();

            System.out.println("alert.getWidth() = " + alert.getWidth());
            System.out.println("alert.getHeight() = " + alert.getHeight());

            alert.setX(bounds.getMaxX() - alert.getWidth());
            alert.setY(bounds.getMaxY() - alert.getHeight());
            alert.showAndWait();
        });

        stackPane.getChildren().add(alertButton);

        return stackPane;
    }
}

但是它的位置是在左上角。原因是 alert.getWidth() 和 alert.getHeight() 总是返回 NaN。我已经尝试过 Platform.runLater()，不幸的是没有用。

如何解决？

Answer 1

使用硬编码的警报宽度和高度设置alert.setX()和alert.setY()并在Action中实例化Alert事件

private Parent createContent() {

        StackPane stackPane = new StackPane();

        Button alertButton = new Button("Alert test");
        alertButton.setOnAction(event -> {

            Alert alert = new Alert(Alert.AlertType.ERROR);
            alert.setTitle("Error Dialog");
            alert.setHeaderText("Something went wrong");
            alert.setContentText("There is an error!");
            Rectangle2D bounds = Screen.getPrimary().getVisualBounds();
            alert.setX(bounds.getMaxX() - 366);
            alert.setY(bounds.getMaxY() - 185);

            alert.showAndWait();

        });

        stackPane.getChildren().add(alertButton);

        return stackPane;
    }