Javafx 2 如何在控制器类中交换JavaFX应用程序中的屏幕?
如果JavaFX项目中有3个文件;FXML文件、FXML控制器和应用程序类;控制器如何通过更改按钮点击时的屏幕(通常通过Javafx 2 如何在控制器类中交换JavaFX应用程序中的屏幕?,javafx-2,javafx,Javafx 2,Javafx,如果JavaFX项目中有3个文件;FXML文件、FXML控制器和应用程序类;控制器如何通过更改按钮点击时的屏幕(通常通过stage.setScreen())来响应按钮点击(工作正常)?我没有对stage的引用(它被传递到应用程序类的start(stage)) 应用程序示例: public class JavaFXApplication4 extends Application { @Override public void start(Stage stage) throws E
stage.setScreen()
)来响应按钮点击(工作正常)?我没有对stage的引用(它被传递到应用程序类的start(stage)
)
应用程序示例:
public class JavaFXApplication4 extends Application {
@Override
public void start(Stage stage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource("Sample.fxml"));
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
/**
* The main() method is ignored in correctly deployed JavaFX application.
* main() serves only as fallback in case the application can not be
* launched through deployment artifacts, e.g., in IDEs with limited FX
* support. NetBeans ignores main().
*
* @param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
}
FXML样本:
<?xml version="1.0" encoding="UTF-8"?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<AnchorPane id="AnchorPane" prefHeight="200.0" prefWidth="320.0" xmlns:fx="http://javafx.com/fxml" fx:controller="javafxapplication4.SampleController">
<children>
<Button id="button" fx:id="nextScreen" layoutX="126.0" layoutY="90.0" onAction="#handleButtonAction" text="Next Screen" />
<Label fx:id="label" layoutX="126.0" layoutY="120.0" minHeight="16.0" minWidth="69.0" />
</children>
</AnchorPane>
当我进入Java并试图解决同样的问题时,我发现了这个老问题。 因为我想让场景记住开关之间的内容,所以我不能使用接受的答案,因为在场景之间切换时,它会再次实例化它们(失去它们以前的状态) 不管怎样,被接受的答案和答案给了我一些提示,告诉我如何在不失去状态的情况下切换场景。 其主要思想是将场景的实例注入到另一个控制器中,这样控制器就不需要反复实例化一个新的场景,而是可以使用已经存在的实例(及其状态) 下面是实例化场景的主类:
public class Main extends Application {
public static void main(String[] args) {
launch(args);
}
@Override
public void start(Stage primaryStage) throws Exception {
// getting loader and a pane for the first scene.
// loader will then give a possibility to get related controller
FXMLLoader firstPaneLoader = new FXMLLoader(getClass().getResource("firstLayout.fxml"));
Parent firstPane = firstPaneLoader.load();
Scene firstScene = new Scene(firstPane, 300, 275);
// getting loader and a pane for the second scene
FXMLLoader secondPageLoader = new FXMLLoader(getClass().getResource("secondLayout.fxml"));
Parent secondPane = secondPageLoader.load();
Scene secondScene = new Scene(secondPane, 300, 275);
// injecting second scene into the controller of the first scene
FirstController firstPaneController = (FirstController) firstPaneLoader.getController();
firstPaneController.setSecondScene(secondScene);
// injecting first scene into the controller of the second scene
SecondController secondPaneController = (SecondController) secondPageLoader.getController();
secondPaneController.setFirstScene(firstScene);
primaryStage.setTitle("Switching scenes");
primaryStage.setScene(firstScene);
primaryStage.show();
}
}
以下是两个控制器:
public class FirstController {
private Scene secondScene;
public void setSecondScene(Scene scene) {
secondScene = scene;
}
public void openSecondScene(ActionEvent actionEvent) {
Stage primaryStage = (Stage)((Node)actionEvent.getSource()).getScene().getWindow();
primaryStage.setScene(secondScene);
}
}
是的,第二个看起来是一样的(一些逻辑可能是共享的,但当前状态足以作为概念证明)
你也可以这样试试
public void onBtnClick(ActionEvent event) {
try {
FXMLLoader loader = new FXMLLoader(getClass().getResource("login.fxml"));
Stage stage = (Stage) btn.getScene().getWindow();
Scene scene = new Scene(loader.load());
stage.setScene(scene);
}catch (IOException io){
io.printStackTrace();
}
}
非常感谢,这正是我想要的:)这非常有帮助!谢谢:)当您在“stage.setScene(…)”结尾处键入时,“stage”必须是两个“stageEventSourceNodeBelongs”或“stageTheLabelLongs”中的一个“对吗?天哪,这救了我的命!我一直在互联网上搜寻类似的东西,因为所有其他示例每次都从文件中加载资源,但我需要保留场景对象,所以谢谢!正是我需要的!一旦解释清楚了就很明显了。非常感谢。
public class FirstController {
private Scene secondScene;
public void setSecondScene(Scene scene) {
secondScene = scene;
}
public void openSecondScene(ActionEvent actionEvent) {
Stage primaryStage = (Stage)((Node)actionEvent.getSource()).getScene().getWindow();
primaryStage.setScene(secondScene);
}
}
public class SecondController {
private Scene firstScene;
public void setFirstScene(Scene scene) {
firstScene = scene;
}
public void openFirstScene(ActionEvent actionEvent) {
Stage primaryStage = (Stage)((Node)actionEvent.getSource()).getScene().getWindow();
primaryStage.setScene(firstScene);
}
}
public void onBtnClick(ActionEvent event) {
try {
FXMLLoader loader = new FXMLLoader(getClass().getResource("login.fxml"));
Stage stage = (Stage) btn.getScene().getWindow();
Scene scene = new Scene(loader.load());
stage.setScene(scene);
}catch (IOException io){
io.printStackTrace();
}
}