JavaFX 加载 FXML 的性能问题

Question

我有一个带有切换按钮的主文件，单击其中一个按钮后，我会启动一个新的 FXMLLoader，其中包含大约 10 个 SVG、15 个文本字段和 6 个微调器。此外，它有 CSS 相应地渲染节点...它加载正常，没有错误或任何问题，但在显示场景之前需要一两秒。

我猜这是由于同时初始化的节点数量所致。有没有办法在节点开始初始化之前显示场景？

注意：我的项目需要我在点击时导航到不同的场景。

ToggleButton 从它被选中的地方

   if(settings.isSelected()){
        Stage stage = (Stage) mainWrapper.getScene().getWindow();
        Parent root = FXMLLoader.load(getClass().getResource("/fxmlFiles/settings.fxml"));
        stage.setScene(new Scene(root, Screen.getPrimary().getVisualBounds().getWidth(),
                Screen.getPrimary().getVisualBounds().getHeight()));
        stage.centerOnScreen();
        //stage.setMaximized(true);
        stage.show();
    }

fxml文件

    <FlowPane xmlns:fx="http://javafx.com/fxml"
    fx:controller="controllers.motelInfoController"
    stylesheets="/cssFiles/motelInfo.css"
    fx:id="content">

    <VBox fx:id="mainWrapper">
    <VBox fx:id="validationWrapper">
        <Label fx:id="validationLabel" visible="false"/>
    </VBox>
    <VBox fx:id="generalInfo">
    <HBox> <!--First Row-->
            <HBox>
            <Group>
                <SVGPath fx:id="iconMotelName" scaleX="0.05" scaleY="0.05" fill="white"/>
            </Group>
            <Group>
                <TextField fx:id="miName" promptText="Motel Name"/>
            </Group>
            </HBox>
            <HBox>
                <Group>
                    <TextField fx:id="miFranchiseName" promptText="Franchise Name"/>
                </Group>
            </HBox>
        </HBox>
    <HBox> <!--Second Row-->
            <HBox>
                <Group>
                    <SVGPath fx:id="iconMotelAddress" scaleX="0.05" scaleY="0.05" fill="white"/>
                </Group>
                <Group>
                    <TextField fx:id="miAddress" promptText="Street Name"/>
                </Group>
            </HBox>
            <HBox>
                <Group>
                <TextField fx:id="miCity" promptText="City/Town Name"/>
                </Group>
            </HBox>
        </HBox>
    <HBox><!--Third Row-->
            <HBox style="-fx-spacing: 25px;">
                <Label></Label> <!--Empty label for purpose of leaving icon gap since N/A here-->
                <Group>
                    <TextField fx:id="miState" promptText="State"/>
                </Group>
            </HBox>
            <HBox>
                <Group>
                    <TextField fx:id="miZipCode" promptText="Zip Code"/>
                </Group>
            </HBox>
            <HBox>
                <Group>
                    <SVGPath fx:id="iconMotelContact" scaleX="0.05" scaleY="0.05" fill="white"/>
                </Group>
                <Group>
                    <TextField fx:id="miContact" promptText="Contact no."/>
                </Group>
            </HBox>
        </HBox>
    <HBox> <!--Fourth Row-->
            <HBox>
                <Group>
                    <SVGPath fx:id="iconMotelFax" scaleX="0.05" scaleY="0.05" fill="white"/>
                </Group>
                <Group>
                    <TextField fx:id="miFax" promptText="Fax no."/>
                </Group>
            </HBox>
            <HBox>
                <Group>
                    <SVGPath fx:id="iconMotelEmail" scaleX="0.05" scaleY="0.05" fill="white"/>
                </Group>
                <Group>
                    <TextField fx:id="miEmail" promptText="Email id"/>
                </Group>
            </HBox>
            <HBox>
                <Group>
                    <SVGPath fx:id="iconMotelNoOfRooms" scaleX="0.05" scaleY="0.05" fill="white"/>
                </Group>
                <Group>
                    <TextField fx:id="miNOR" promptText="No. of Rooms"/>
                </Group>
            </HBox>
        </HBox>
    <HBox style="-fx-spacing: 50px"> <!--Fifth Row-->
            <HBox>
                <Group>
                    <SVGPath fx:id="iconMotelCheckInTime" scaleX="0.05" scaleY="0.05" fill="white"/>
                </Group>
                <Group>
                    <Spinner fx:id="hourSpinnerCIT"/>
                </Group>
                <Group>
                    <Spinner fx:id="minSpinnerCIT"/>
                </Group>
                <Group>
                    <Spinner fx:id="secSpinnerCIT"/>
                </Group>
            </HBox>
            <HBox>
                <Group>
                    <SVGPath fx:id="iconMotelCheckOutTime" scaleX="0.05" scaleY="0.05" fill="white"/>
                </Group>
                <Group>
                    <Spinner fx:id="hourSpinnerCOT"/>
                </Group>
                <Group>
                    <Spinner fx:id="minSpinnerCOT"/>
                </Group>
                <Group>
                    <Spinner fx:id="secSpinnerCOT"/>
                </Group>
            </HBox>
        </HBox>
    </VBox>
    <VBox fx:id="roomOccupancy">
    <HBox> <!--First Row-->
            <Label fx:id="labelMaxGuestSelection"
                   text="Maximum Allowed Guest in individual Rooms. Please state the max count in adjacent cells"/>
            <VBox>
                <HBox>
                    <Group>
                        <SVGPath fx:id="iconMotelSingleBed" scaleX="0.05" scaleY="0.05" fill="white"/>
                    </Group>
                    <Group>
                        <TextField fx:id="miSB" promptText="Single Bed"/>
                    </Group>
                </HBox>
                <HBox>
                    <Group>
                        <SVGPath fx:id="iconMotelTwoBeds" scaleX="0.05" scaleY="0.05" fill="white"/>
                    </Group>
                    <Group>
                        <TextField fx:id="miTB" promptText="Two Beds"/>
                    </Group>
                </HBox>
                <HBox>
                    <Group>
                        <SVGPath fx:id="iconMotelfamilyRoom" scaleX="0.05" scaleY="0.05" fill="white"/>
                    </Group>
                    <Group>
                        <TextField fx:id="miFR" promptText="Family Room"/>
                    </Group>
                </HBox>
            </VBox>
        </HBox>
    <HBox> <!--Second Row-->
            <Label fx:id="labelMaxGuestCharged"
                    text="Rate Charged per Guest after max. allowed guest exceeds in a room"/>
            <HBox>
                <Group>
                    <SVGPath fx:id="iconMotelGuestExceedRate" scaleX="0.05" scaleY="0.05" fill="white"/>
                </Group>
                <Group>
                    <TextField fx:id="miGER" promptText="Rate/Guest Exceeded"/>
                </Group>
            </HBox>
        </HBox>
    </VBox>
    <VBox fx:id="submissionWrapper">
    <Group>
    <Button fx:id="submit" text="UPDATE" onAction="#saveData"/>
    </Group>
    </VBox>
    </VBox>

    </FlowPane>

FXML 控制器

@Override
public void initialize(URL location, ResourceBundle resources) {

    //Load the data if the motelInfo file exist
    File checkTemp = new File("motelDetails.ser");
    if(checkTemp.exists()){
        readDataFromFile();
    }

    //Getting Values for the spinner
    for(int i=0;i<24;i++){
        hourList.add(String.format("%02d", i));
    }
    final SpinnerValueFactory<String> hourValuesCIT = new SpinnerValueFactory.ListSpinnerValueFactory<>(hourList);
    final SpinnerValueFactory<String> hourValuesCOT = new SpinnerValueFactory.ListSpinnerValueFactory<>(hourList);
    for(int i=0; i<60; i++){
        minList.add(String.format("%02d", i));
        secList.add(String.format("%02d", i));
    }
    final SpinnerValueFactory<String> minValuesCIT = new SpinnerValueFactory.ListSpinnerValueFactory<>(minList);
    final SpinnerValueFactory<String> minValuesCOT = new SpinnerValueFactory.ListSpinnerValueFactory<>(minList);
    final SpinnerValueFactory<String> secValuesCIT = new SpinnerValueFactory.ListSpinnerValueFactory<>(secList);
    final SpinnerValueFactory<String> secValuesCOT = new SpinnerValueFactory.ListSpinnerValueFactory<>(secList);

    styleSpinner(hourSpinnerCIT, hourValuesCIT);
    styleSpinner(hourSpinnerCOT, hourValuesCOT);
    styleSpinner(minSpinnerCIT, minValuesCIT);
    styleSpinner(minSpinnerCOT, minValuesCOT);
    styleSpinner(secSpinnerCIT, secValuesCIT);
    styleSpinner(secSpinnerCOT, secValuesCOT);


}

Answer 1

看来你有两个问题：

运行在阻塞更新的 UI 线程上进行长时间操作 (readDataFromFile())
在 FXMLoader.load() 中完成所有操作，在完成之前不允许绘制任何东西

我建议通过运行在不同的线程中加载并在加载时显示加载屏幕来解决这两个问题。请参阅下一个示例：

public class Main extends Application {

    @Override
    public void start(Stage stage) throws Exception {
        StackPane loadingRoot = new StackPane();

        loadingRoot.getChildren().setAll(new ProgressIndicator());
        final Scene scene = new Scene(loadingRoot);

        stage.setWidth(400);
        stage.setHeight(400);
        stage.setScene(scene);
        stage.show();

        new Thread(() -> {
            veryLongOperation();

            // we need to wrap UI code in Platform
            Platform.runLater(() -> {
                Parent root;
                try {
                    root = FXMLLoader.load(Main.class.getResource("FXMLDocument.fxml"));
                    scene.setRoot(root);
                } catch (IOException ex) {
                }
            });
        }).start();
    }

    public static void veryLongOperation() {
            try {
                // long-long operation
                Thread.sleep(5000);
            } catch (Exception ex) {
            }

    }
}

JavaFX 加载 FXML 的性能问题

JavaFX loading performance problems with FXML

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javafx-8