Swap scene after login from main class method

[sand tartan]

public class main_gui_class extends Application {
    @Override
    public void start(Stage stage) throws IOException {
        log_in_scene(stage);



    }
    public void log_in_scene(Stage stage) throws IOException{
        FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("log_in_page.fxml"));
        Parent root = fxmlLoader.load();

        Scene scene = new Scene(root);

        stage.setTitle("Hello!");
        stage.setScene(scene);
        stage.show();


    }

    public void home_page_scene(Stage stage) throws IOException {
        FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("home_page.fxml"));
        Parent root = fxmlLoader.load();

        Scene scene = new Scene(root);

        stage.setTitle("Hello!");
        stage.setScene(scene);
        stage.show();
    }

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

public class login_controller {
    @FXML
    private TextField username;

    @FXML
    private TextField password;

    private Stage stage;




    String user = "admin";
    String pass = "admin1";

    @FXML
    protected void loginClicked(ActionEvent event) throws IOException {

        if (username.getText().equals(user) && password.getText().equals(pass)){
            // Call it from here
            System.out.println("SUCCESS");



        }else {
            System.out.println("INVALID PASSWORD");
        }


    }
}

I want to call the home_page_scene from the login controller

[broken pecan]

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[queen blade]

you need an instance of main_gui_class in your controller

so you can add a field and a setter for it

and when loading the FXML, you can do

login_controller ctl = (login_controller) fxmlLoader.getController();
ctl.setMainClass(this);

btw class names should be PascalCase by convention

not snake_case

[noble galleon]

First of all make a static library for all of ur scenes:

public class SceneLoader {
  public static final String LOG_IN = "log_in_page.fxml";
  public static final String HOME_PAGE = "...";
  //it would be even better if u make an enum for these strings, since that prevents load being called with any random BS

  public static Parent load(final String scene) {
    try {
      Path resource = getClass().getResource(scene);
      if (resource == null) throw new FileNotFounException(
            "The FXML scene: \"%s\" was not found in the resource folder"
            .formatted(scene));

      return new FXMLLoader(resource).load();

    } catch (IOException e) {
      throw new IllegalStateException(
            "Unable to read the file \"%s\" when loading a scene"
            .formatted(scene),
            e);
    }
  }

this gives u the error handling u are completely missing from ur code,
deals with the Checked exception
AND removes the code duplication in ur program

Then you would save the stage given to u in the start method and write a method load scenes, again removing code duplication to use that stage plus whatever loaded scene given to it

and then u have a choice, as dan1st shows above u can set the main class in the controllers after the FXMLLoader makes them (which means u have the publically accessable set method than can mess things up by accident

or u can construct the controllers ahead of time with a link to Main

[queen blade]

tbh I prefer the DI way but both options work

i.e. with a setter (possibly in an interface or abstract class)

[sand tartan]

Any tips on or tutorial on the right way to make javafx gui? I am more of a python guy and I have to use java for schools

[noble galleon]

the same principles apply in python and java

[sand tartan]

yeah, but I am a bit confused with the syntax

[noble galleon]

loose coupling, single responsibility, law of demeter, no magic numbers, readibility, consistant style, etc

[sand tartan]

btw this class sceneloader, is where I put all scene fxml?

[noble galleon]

did u create a maven project?

[sand tartan]

I did

The features are too good

[noble galleon]

then it generated the correct paths already
.... /src/java/main/resources or something ... u can put a folder in there to group them together if u like, but thats the exact correct place for support files for the project

[sand tartan]

aight

btw so I finally understand that the scene builder is basically just a method that makes scene instance thingly less of a struggle and confusing

[noble galleon]

yeah, r u using the new gluon one of the old oracle one?

the scenebuilder integrates perfectly with intelliJ, giving u code completion for controller names etc