[FIXED] Create a reusable button with function paramater

Issue

I want to have a reusable button in JavaFX and give a function to it.

I currently have this:

BackButtonController

public class BackButtonController {
@FXML
private Button btnBack;

private final Method method;

    public BackButtonController(Method method) {
        this.method = method;
    }

    @FXML
    protected void initialize() {
        this.btnBack.setOnMouseClick(() -> buttonClick());
    }

    public void btnClick() {
        // do the received function
    }

}

BackButton.fxml

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.Button?>
<?import javafx.scene.layout.AnchorPane?>


<AnchorPane xmlns="http://javafx.com/javafx/11.0.1" xmlns:fx="http://javafx.com/fxml/1">
    <Button fx:id="btnBack" mnemonicParsing="false" text="Back" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0"
        AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0"/>
</AnchorPane>

Controller

protected void initialize() {
    try {
        var loader = new FXMLLoader(getClass().getResource("/views/backButton.fxml"));
        loader.setController(new BackButtonController(this.test()));
        this.vbPanel.getChildren().add(0, loader.load());
    } catch (IOException e) {
        e.printStackTrace();
    }
    // some other code
}

I want to be able to load the button with a function that I send to the controller so when the button is pressed it runs that function.

I have been looking online but I can't get this to work.

I hope someone can help me with this.

Solution

I would replace the Method with a Runnable object. Then, on button clicked, execute that Runnable.

Like so:

public class BackButtonController {
@FXML
private Button btnBack;

private final Runnable runnable;

public BackButtonController(Runnable r) {
    this.runnable= r;
}

@FXML
protected void initialize() {
    this.btnBack.setOnMouseClick(() -> buttonClick());
}

public void btnClick() {
    runnable.run();
//Alternatively, if you want to run it in a separate Thread, use 
    new Thread(runnable).start();
}

}

Answered By - AdminOfThis