使用 JavaFX 的应用程序中心未显示警报框 [重复]

Question

我试图在调整应用程序大小或移动应用程序时弹出应用程序中心的框。 我尝试使用 css 对齐并使用 Java。如果我不使用窗格并直接在场景中添加框，是否可以？

这是我的代码：

public Boolean call(String question) {
  final Stage dialogStage = new Stage(StageStyle.UNDECORATED);
  dialogStage.initModality(Modality.WINDOW_MODAL);
  dialogStage.initOwner(owner);
  dialogStage.setTitle("ConfirmTitle"); // WIP, waiting for the strings&trans
  final Button ok = new Button(
      nmsGuiContainer.getI18nService().getMessage("com.mlnms.gui.fmwk.main.container.ok")); // WIP,
                                                                                            // waiting
                                                                                            // for
                                                                                            // the
  // strings&trans
  ok.getStyleClass().add(HTML_POPUP_BUTTON_STYLE);
  final Button cancel = new Button(
      nmsGuiContainer.getI18nService().getMessage("com.mlnms.gui.fmwk.main.container.cancel")); // WIP,
                                                                                                // waiting
  // for the
  // strings&trans
  cancel.getStyleClass().add(HTML_POPUP_BUTTON_STYLE);
  final Text text = new Text(question);
  text.getStyleClass().add(HTML_POPUP_STYLE);
  final Insets ins = new Insets(10);
  final VBox box = new VBox();
  box.setAlignment(Pos.BOTTOM_CENTER);
  box.setSpacing(10);
  box.setPadding(ins);
  final HBox buttons = new HBox(10);
  buttons.getChildren().addAll(ok, cancel);
  buttons.setAlignment(Pos.CENTER);
  buttons.setPadding(ins);
  box.getChildren().addAll(text, buttons);
  box.getStyleClass().add(HTML_POPUP_STYLE);
  StackPane pane = new StackPane();
  pane.setAlignment(box, Pos.CENTER);
  pane.getChildren().add(box);
  Scene scene = new Scene(pane);
  try {
    URL javafxCss = nmsGuiContainer.getBundleContext().getBundle()
        .getResource(NmsGuiContainer.JAVAFX_CSS_URL);
    scene.getStylesheets().add(javafxCss.toExternalForm());

  } catch (Exception e) {
    LOGGER.error("Cannot load the CSS file for JavaFX components ", e);
  }
  dialogStage.setScene(scene);
  ok.setCancelButton(false);

  final boolean[] res = new boolean[1];
  ok.setOnAction(new CloseDialogHandler(dialogStage, res));
  cancel.setCancelButton(true);
  cancel.setOnAction(new CloseDialogHandler(dialogStage, null));
  dialogStage.centerOnScreen();
  nmsGuiContainer.fadeContainer();
  dialogStage.showAndWait();
  nmsGuiContainer.unfadeContainer();
  return res[0];
}

这里是alertbox的截图：

Answer 1

Stage.initOwner() 方法完全符合您的需要。虽然您确实在示例代码中调用了它，但我不知道您传递给它的是什么 owner。

这是一个演示如何执行此操作的示例。

import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Alert;
import javafx.scene.control.Button;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class Main extends Application {

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

    @Override
    public void start(Stage primaryStage) {

        VBox root = new VBox(10);
        root.setAlignment(Pos.CENTER);
        root.setPadding(new Insets(10));

        Button btnShowAlert = new Button("Show Alert!");

        // Set the action to show the alert
        btnShowAlert.setOnAction(e -> {
            Alert alert = new Alert(Alert.AlertType.WARNING);
            alert.setHeaderText("This is centered over the main window!");
            alert.setContentText("Move the main window and show the alert again!");

            alert.initOwner(primaryStage);
            alert.showAndWait();

        });

        root.getChildren().add(btnShowAlert);

        primaryStage.setTitle("Centered Alerts");
        primaryStage.setScene(new Scene(root));
        primaryStage.setWidth(500);
        primaryStage.setHeight(300);

        primaryStage.show();
    }
}