import javafx.application.Application;
    import javafx.fxml.FXMLLoader;
    import javafx.stage.Stage;
    import javafx.scene.Parent;
    import javafx.scene.Scene;
    import javafx.scene.layout.BorderPane;


    public class Main extends Application {
        @Override
        public void start(Stage primaryStage) {
            try {
                Parent root=FXMLLoader.load(getClass().getResource("/application/Login.fxml"));
                Scene scene = new Scene(root,400,400);
                scene.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
                primaryStage.setScene(scene);
                primaryStage.show();
            } catch(Exception e) {
                e.printStackTrace();
            }
        }

        public static void main(String[] args) {
            launch(args); // tried changing this to string[0] didnt work
        }
    }

package application;

import java.awt.Label;
import java.awt.TextField;
import java.awt.event.ActionEvent;

import javafx.fxml.FXML;

public class MainController {

    @FXML
    private Label LblStatus;
@FXML
private TextField TxtUsername;
@FXML
private TextField TxtPassword;
public void Login(ActionEvent event)
{

     LblStatus.setText("Login sucsess");
}
}

login page

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

<?import java.lang.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.text.*?>

<AnchorPane prefHeight="400.0" prefWidth="500.0" xmlns:fx="http://javafx.com/fxml/1" xmlns="http://javafx.com/javafx/2.2" fx:controller="application.MainController">
  <!-- TODO Add Nodes -->
  <children>
    <Pane prefHeight="400.0" prefWidth="500.0" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0">
      <children>
        <TitledPane animated="false" layoutX="0.0" layoutY="0.0" prefHeight="400.0000999999975" prefWidth="500.0" text="LOGIN FORM" textAlignment="CENTER" wrapText="false">
          <content>
            <AnchorPane id="Content" minHeight="0.0" minWidth="0.0" prefHeight="180.0" prefWidth="200.0">
              <children>
                <TextField fx:id="TxtUsername" layoutX="227.0" layoutY="129.0" prefWidth="200.0" promptText="Enter Username" />
                <Label layoutX="129.0" layoutY="129.0" prefWidth="98.0" text="USERNAME:">
                  <font>
                    <Font size="15.0" fx:id="x1" />
                  </font>
                </Label>
                <Label font="$x1" layoutX="129.0" layoutY="183.0" prefWidth="98.0" text="PASSWORD:" />
                <Button font="$x1" layoutX="224.0" layoutY="225.0" mnemonicParsing="false" onAction="#Login" text="LOGIN" />
                <PasswordField fx:id="TxtPassword" layoutX="224.0" layoutY="183.0" prefWidth="200.0" promptText="Enter Password" />
                <Label id="Status" fx:id="LblStatus" layoutX="259.0" layoutY="69.0" text="Status">
                  <font>
                    <Font size="20.0" />
                  </font>
                </Label>
              </children>
            </AnchorPane>
          </content>
          <font>
            <Font name="Arial Black" size="15.0" />
          </font>
        </TitledPane>
      </children>
    </Pane>
  </children>
</AnchorPane>