JavaFX: Alert 弹窗

Posted 2022-12-10 xhBruce

JavaFX: Alert 弹窗

JavaFX视频教程第22课，DialogPane类和ScheduledService多任务的简单使用
JavaFX视频教程第91课，Alert 弹窗
code.makery：JavaFX Dialogs (official)

---

DialogPane 类

https://openjfx.cn/javadoc/16/javafx.controls/javafx/scene/control/DialogPane.html

• 标题 Stage 中设置，其他属性设置如top显示、
• DialogPane 继承Pane，需要添加到Scene、Stage中
• DialogPane 头部文字HeaderText、内容ContentText
• DialogPane 添加 button types 按钮和监听
  

public class DialogController 

    @FXML
    protected void onHelloButtonClick() 
        DialogPane dialog = new DialogPane();
        dialog.setHeaderText(" xhbruce ");
        dialog.setContentText(" Dialog Sampler ");

        dialog.getButtonTypes().add(ButtonType.APPLY);
        dialog.getButtonTypes().add(ButtonType.CANCEL);
        dialog.getButtonTypes().add(ButtonType.CLOSE);
        dialog.getButtonTypes().add(ButtonType.FINISH);
        dialog.getButtonTypes().add(ButtonType.NEXT);
        dialog.getButtonTypes().add(ButtonType.NO);
        dialog.getButtonTypes().add(ButtonType.OK);
        dialog.getButtonTypes().add(ButtonType.PREVIOUS);
        dialog.getButtonTypes().add(ButtonType.YES);

        Button close = (Button)dialog.lookupButton(ButtonType.CLOSE);
        close.setOnAction(event -> 
            System.out.println(" xhbruce 关闭 ");
            dialog.setHeaderText(" xhbruce 关闭 ");
        );
        Button apply = (Button)dialog.lookupButton(ButtonType.APPLY);
        apply.setOnAction(event -> 
            System.out.println(" xhbruce 应用 ");
            dialog.setHeaderText(" xhbruce 应用 ");
        );

        Stage dialogStage = new Stage();
        Scene dialogScene = new Scene(dialog);
        dialogStage.setScene(dialogScene);

        dialogStage.setTitle("退出!");
        dialogStage.initOwner(DialogApplication.PRIMARY_STAGE);
        dialogStage.initStyle(StageStyle.UTILITY);
        dialogStage.initModality(Modality.WINDOW_MODAL);
        //dialogStage.setAlwaysOnTop(true);
        dialogStage.setResizable(false);
        dialogStage.show();
    

DialogPane 自定义布局

• 图片添加setGraphic
• 扩展内容setExpandableContent
  

        ImageView imageView = new ImageView(PathInfo.getImage("kotlin-android.PNG"));
        dialog.setGraphic(imageView);

        dialog.setExpandableContent(new Text(" 扩展内容 "));

• 添加自定义fxml布局（界面闪烁）
  

        Node content = PathInfo.loadfxml("expandable.fxml");
        dialog.setContent(content);

---

Alert 类

https://openjfx.cn/javadoc/16/javafx.controls/javafx/scene/control/Alert.html

AlertType 类型

    public static enum AlertType 
        /**
         * The NONE alert type has the effect of not setting any default properties
         * in the Alert.
         */
        NONE,

        /**
         * The INFORMATION alert type configures the Alert dialog to appear in a
         * way that suggests the content of the dialog is informing the user of
         * a piece of information. This includes an 'information' image, an
         * appropriate title and header, and just an OK button for the user to
         * click on to dismiss the dialog.
         */
        INFORMATION,

        /**
         * The WARNING alert type configures the Alert dialog to appear in a
         * way that suggests the content of the dialog is warning the user about
         * some fact or action. This includes a 'warning' image, an
         * appropriate title and header, and just an OK button for the user to
         * click on to dismiss the dialog.
         */
        WARNING,

        /**
         * The CONFIRMATION alert type configures the Alert dialog to appear in a
         * way that suggests the content of the dialog is seeking confirmation from
         * the user. This includes a 'confirmation' image, an
         * appropriate title and header, and both OK and Cancel buttons for the
         * user to click on to dismiss the dialog.
         */
        CONFIRMATION,

        /**
         * The ERROR alert type configures the Alert dialog to appear in a
         * way that suggests that something has gone wrong. This includes an
         * 'error' image, an appropriate title and header, and just an OK button
         * for the user to click on to dismiss the dialog.
         */
        ERROR
    

• NONE

        Alert alert = new Alert(Alert.AlertType.CONFIRMATION, "Are you sure you want to format your system?");
        alert.showAndWait();

• INFORMATION
  
• WARNING
  
• CONFIRMATION
  
• ERROR
  

Alert 相关属性

• 基础标题、头部文字HeaderText、内容ContentText、一个图标
• Button 添加并监听反馈按钮操作
• 位于stage的top，Alert显示后底部不可操作

public class DialogController 

    @FXML
    protected void onHelloButtonClick() 
        Alert alert = createAlert(AlertType.NONE,
                " Xhbruce Alert ",
                " Header Text ",
                " Content Text ",
                null,
                DialogApplication.PRIMARY_STAGE,
                new ImageView(PathInfo.getImage("kotlin-Android.PNG")));

        alert.getButtonTypes().add(ButtonType.CANCEL);
        alert.getButtonTypes().add(ButtonType.CLOSE);

        ButtonType buttonTypeOne = new ButtonType("One");
        ButtonType buttonTypeCancel = new ButtonType("XhBruce 应用", ButtonBar.ButtonData.APPLY);

        alert.getButtonTypes().addAll(buttonTypeOne, buttonTypeCancel);
        //alert.getButtonTypes().setAll(buttonTypeOne, buttonTypeCancel);

        Optional<ButtonType> result = alert.showAndWait();
        ButtonType buttonType = result.get();
        if (buttonType == ButtonType.CANCEL)
            System.out.println(" ButtonType.CANCEL ");
         else if (buttonType == ButtonType.CLOSE) 
            System.out.println(" ButtonType.CLOSE ");
         else if (buttonType == buttonTypeOne) 
            System.out.println(" ButtonTypeOne ");
         else 
            System.out.println(" ButtonType ");
        

    

    // Alert 弹框
    private Alert createAlert(AlertType alertType, String title, String headerText, String contentText,
                             StageStyle stageStyle, Stage owner, Node graphic) 
        Alert alert = new Alert(alertType);
        if (title != null) 
            alert.setTitle(title);
        
        if (headerText != null) 
            alert.setHeaderText(headerText);
        
        if (contentText != null) 
            alert.setContentText(contentText);
        
        if (stageStyle != null) 
            alert.initStyle(stageStyle);
        
        if (owner != null) 
            alert.initOwner(owner);

            alert.heightProperty().addListener(l -> 
                double centerX = owner.getX() + owner.getWidth() / 2;
                double centerY = owner.getY() + owner.getHeight() / 2;

                double alertWidth = alert.getWidth();
                double alertHeight = alert.getHeight();
                double alertScreenX = centerX - alert.getWidth() / 2;
                double alertScreenY = centerY - alert.getHeight() / 2;

                //System.out.println("alert : alertScreenX=" + alertScreenX + ",alertScreenY=" + alertScreenY);
                //System.out.println("alert : alertWidth=" + alertWidth + ",alertHeight=" + alertHeight);

                if (alertScreenX + alertWidth > JavaFXTool.getVisualScreenWidth())
                    alertScreenX = (int) (JavaFXTool.getVisualScreenWidth() - alertWidth);
                else if (alertScreenX < 0) 
                    alertScreenX = 0;
                

                if (alertScreenY + alertHeight > JavaFXTool.getVisualScreenHeight()) 
                    alertScreenY = (int) (JavaFXTool.getVisualScreenHeight() - alertHeight);
                 else if (alertScreenY < 0) 
                    alertScreenY = 0;
                

                // Set the X and Y of the Alert
                alert.setX(alertScreenX);
                alert.setY(alertScreenY);
            );
        

        if (graphic != null) 
            alert.setGraphic(graphic);
        

        //alert.showAndWait();
        return alert;