JavaFX, FXMLLoader.setController(controller) doesn't load scene
<p>Keep freezing when on setController. It doesn't load scene when user and password are enter</p>

<pre><code>import java.io.IOException;
import java.sql.*;
import javafx.collections.*;
import javafx.event.Event;
import javafx.fxml.*;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.stage.Stage;

public class GiantsLoginController {

public String dataName, serverName, password;
public int num;

private Connection connect = null;
private Statement stmt = null;

private boolean userPass, connected;

private Connections connection;


@FXML
private ComboBox&lt;String&gt; sType;
@FXML
public TextField dbName;
@FXML
private TextField sName;
@FXML
private Button loginB;
@FXML
private PasswordField sPassword;
@FXML
private Pane paneL;
@FXML
private GridPane gPane;
@FXML
private ComboBox&lt;String&gt; uType;


ObservableList&lt;String&gt; sLists = FXCollections.observableArrayList("MySQL LOCAL", 
        "MYSQL REMOTE", "SQL SERVER LOCAL", "SQL SERVER");
ObservableList&lt;String&gt; uList = FXCollections.observableArrayList("Player", 
        "Admin");



@FXML
public void initialize() {
    sType.setItems(sLists);
    uType.setItems(uList);
}

@FXML
public void loginBClick (Event event) {
    if (isAllFieldFillup()) {

        switch(uType.getValue().trim()) {
            case "Admin":
                if (connectCheck()) {
                    try {

                          changeStage(GiantsLogin.getPrimaryStage());

                    }
                    catch (Exception e) {

                    }
                }
            case "Player": 
                if (connectCheck()) {
                    try {

                    }
                    catch (Exception e) {

                    }
                }
        }
    }
}

public void changeStage(Stage stage) throws IOException {
    GiantsAdminController controller = new GiantsAdminController("Hello World!");
    FXMLLoader loader = FXMLLoader.load(getClass().getResource("GiantsAdmin.fxml"));
    loader.setController(controller);
    stage.hide();
    stage.setScene(new Scene((Pane) loader.load()));
    stage.show();
}

public void closeConnection () {

    if (connect != null) {
        try {
            stmt.close();
            connect.close();
        }
        catch (SQLException e) {

        }
    }
}

public boolean connectCheck() {
    connected = false;

    dataName = dbName.getText();
    serverName = sName.getText();
    password = sPassword.getText();


    switch (sType.getValue()) {
        case "MySQL LOCAL":
            num = 1;
            break;
        case "MYSQL REMOTE":
            num = 2;
            break;
        case "SQL SERVER LOCAL":
            num = 3;
            break;
        case "SQL SERVER":
            num = 4;
            break;
        default:

    }

    if (connect == null) {
        connect = Connections.getconnect(num, dataName, serverName, password);
    }

    if (connect == null ) {
        System.out.println("Still no connection");
    }

    if (stmt == null) {
        try {
            stmt = connect.createStatement();
            connected = true;
        } catch (SQLException e) {
            Alert notify = new Alert(Alert.AlertType.INFORMATION);
            notify.setTitle("Blank filed");
            notify.setHeaderText(null);
            notify.setContentText("Incorrect login.");
            notify.showAndWait();

            connected = false;
        }


    }
    return connected;
}

private boolean isAllFieldFillup() {
    boolean allInfo;
    if (sType.getValue().equals("server type") &amp;&amp; dbName.getText().isEmpty()
            &amp;&amp; sName.getText().isEmpty() &amp;&amp; sPassword.getText().isEmpty()) {
        Alert notify = new Alert(Alert.AlertType.INFORMATION);
        notify.setTitle("Blank filed");
        notify.setHeaderText(null);
        notify.setContentText("You are missing some information.");
        notify.showAndWait();

        allInfo = false;
    }
    else {
        allInfo = true;
    }
    return allInfo;
}

}
</code></pre>

<blockquote>
  <p>This is where I open a new scene and set my controller so I can be
  able to access it in new scene. But it aways frozed when I put the
  user name and password and click login. </p>

<pre><code>public void changeStage(Stage stage) throws IOException {
    GiantsAdminController controller = new GiantsAdminController("Hello World!");
    FXMLLoader loader = FXMLLoader.load(getClass().getResource("GiantsAdmin.fxml"));
    loader.setController(controller);
    stage.hide();
    stage.setScene(new Scene((Pane) loader.load()));
    stage.show();
}
</code></pre>
  
  <p>This is where I am calling the changeStage method this method </p>

<pre><code>public void loginBClick (Event event) {
    if (isAllFieldFillup()) {

        switch(uType.getValue().trim()) {
            case "Admin":
                if (connectCheck()) {
                    try {

                          changeStage(GiantsLogin.getPrimaryStage());

                    }
                    catch (Exception e) {

                    }
                }
            case "Player": 
                if (connectCheck()) {
                    try {

                    }
                    catch (Exception e) {

                    }
                }
        }
    }
}
</code></pre>
  
  <p>This is my main class</p>

<pre><code>import java.io.IOException;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.*;

public class GiantsLogin extends Application {

private static Stage stage;

@Override
public void start(Stage stage) throws IOException {
    setPrimaryStage(stage);
    Parent root = FXMLLoader.load(getClass().getResource("GiantsLogin.fxml"));
    Scene scene = new Scene(root);
    scene.getStylesheets().add(getClass().getResource("style.css").toExternalForm());
    stage.setScene(scene);
    stage.setTitle("Giants Login");
    stage.show();
}

public static void setPrimaryStage(Stage primaryStage) {
    stage = primaryStage;
}

public static Stage getPrimaryStage() {
    return stage;
}
public static void main(String[] args) {
    launch(args);
}

}
</code></pre>
  
  <p>This is my second window: This is the window that supposed to open
  when the user name and pass are correct.</p>

<pre><code>import java.io.IOException;
import java.sql.Statement;
import javafx.collections.*;
import javafx.event.Event;
import javafx.fxml.*;
import javafx.scene.Node;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.stage.Stage;

public class GiantsAdminController {
@FXML
private Button connect = null;
private boolean connected;

private Statement stmt;

@FXML
private TextField aRank;

public GiantsAdminController(String message) {
    System.out.println("You said: " + message);
}

public GiantsAdminController() {
}

ObservableList&lt;String&gt; sLists = FXCollections.observableArrayList("MySQL LOCAL", 
        "MYSQL REMOTE", "SQL SERVER LOCAL", "SQL SERVER");
@FXML
public void initialize() {
    serverType.setItems(sLists);
}

@FXML
public void clearBClick (Event event) {
    aRank.clear();
    aName.clear();
    aPosition.clear();
    aSchool.clear();
    aAge.clear();
    aWar.clear();
}


@FXML
public void SingOutClick(Event event) throws IOException {

    Parent giantsLogin = FXMLLoader.load(getClass().getResource("/giants/GiantsLogin.fxml"));

    Scene gLScene = new Scene(giantsLogin);
    gLScene.getStylesheets().add(getClass().getResource("style.css").toExternalForm());
    stage.setScene(gLScene); 
    stage.show();
}
 }
</code></pre>
</blockquote>

<p>I have try everything to solve this problem, but no luck.</p>