i'm fairly new to javafx and fxml. I'm trying to teach myself! However, when I was creating a program for a simple login GUI I came into an issue when I finally tried to run my program. It told me there was no main method in my class and I'm unsure of how to fix it. Any ideas?
My program creates a login screen and when you enter "test" for the username and password it'll take you to another scene.
Here is my Login.java
package com;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.stage.Stage;
import javafx.scene.Parent;
import javafx.scene.Scene;
/**
*
* #author Tyler
*/
public class Login extends Application{
#Override
public void start(Stage stage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource("Login.fxml"));
Scene scene = new Scene(root);
stage.setScene(scene);
stage.setTitle("Login");
stage.show();
}
}
Here is my LoginController.java
package com;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.fxml.Initializable;
import javafx.scene.Node;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.PasswordField;
import javafx.scene.control.TextField;
import javafx.stage.Stage;
/**
* FXML Controller class
*
* #author Tyler
*/
public class LoginController implements Initializable {
#FXML
private Label lblMessage;
#FXML
private TextField txtUsername;
#FXML
private PasswordField txtPassword;
#FXML
private void btnLoginAction(ActionEvent event) throws Exception{
if(txtUsername.getText().equals("test") && txtPassword.getText().equals("test")){
((Node) (event.getSource())).getScene().getWindow().hide();
Parent parent = FXMLLoader.load(getClass().getResource("DateSelection.fxml"));
Stage stage = new Stage();
Scene scene = new Scene(parent);
stage.setScene(scene);
stage.setTitle("Date Selection");
stage.show();
}else{
lblMessage.setText("Username or Password is invalid!");
}
}
/**
* Initializes the controller class.
* #param url
* #param rb
*/
#Override
public void initialize(URL url, ResourceBundle rb) {
// TODO
}
}
Here is my Login.fxml
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.text.*?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<AnchorPane id="AnchorPane" fx:id="lblMessage" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="com.LoginController">
<children>
<PasswordField fx:id="txtPassword" layoutX="200.0" layoutY="200.0" prefHeight="30.0" prefWidth="200.0" promptText="Password" />
<TextField fx:id="txtUsername" layoutX="200.0" layoutY="140.0" prefHeight="30.0" prefWidth="200.0" promptText="Username" />
<Button fx:id="btnLogin" layoutX="269.0" layoutY="251.0" mnemonicParsing="false" onAction="#btnLoginAction" prefHeight="30.0" text="Login">
<font>
<Font size="14.0" />
</font></Button>
<Label fx:id="lblMessage" layoutX="283.0" layoutY="71.0" text="Label" />
</children>
</AnchorPane>
Here is my DateSelectionController.java
package com;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.fxml.Initializable;
/**
* FXML Controller class
*
* #author Tyler
*/
public class DateSelectionController implements Initializable {
/**
* Initializes the controller class.
*/
#Override
public void initialize(URL url, ResourceBundle rb) {
// TODO
}
}
Here is my DateSelection.fxml
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.text.*?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<AnchorPane id="AnchorPane" prefHeight="400.0" prefWidth="600.0" xmlns:fx="http://javafx.com/fxml/1" xmlns="http://javafx.com/javafx/8" fx:controller="com.DateSelectionController">
<children>
<Label layoutX="191.0" layoutY="164.0" text="Welcome">
<font>
<Font name="System Bold" size="50.0" />
</font>
</Label>
</children>
</AnchorPane>
From Oracle:
The main() method is not required for JavaFX applications when the JAR file for the application is created with the JavaFX Packager tool, which embeds the JavaFX Launcher in the JAR file. However, it is useful to include the main() method so you can run JAR files that were created without the JavaFX Launcher, such as when using an IDE in which the JavaFX tools are not fully integrated. Also, Swing applications that embed JavaFX code require the main() method.
So one solution is to make sure it's being built in a way that fully supports the JavaFX tools. The other solution is to add a main method to starts the application. That would avoid any potential problems like this, and doesn't cause any problems in the case where it's not needed.
Your main method should look like this:
public static void main(String[] args){
Application.launch(Login.class, args);
}
That will simply pass control on to JavaFX to handle like it would normally.
Related
I have installed Scene Builder and opened a new FXML Project just to test it out. I have seen on other computers that when a new FMXL Project is opened, the default code generates a button that displays text when clicked. However, when I try to run the main method of the default FXML Project, I get a stack error with a NullPointerException. I have searched many question threads on how to fix it but none of them really give me a concrete answer. Any help would be appreciated.
## JavaFXApplication2.java ##
package javafxapplication2;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
/**
*
* #author Hafiz
*/
public class JavaFXApplication2 extends Application {
#Override
public void start(Stage stage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource("FXMLDocument.fxml"));
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
## FXMLDocumentController.java ##
}
package javafxapplication2;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Label;
/**
*
* #author Hafiz
*/
public class FXMLDocumentController implements Initializable {
#FXML
private Label label;
#FXML
private void handleButtonAction(ActionEvent event) {
System.out.println("You clicked me!");
label.setText("Hello World!");
}
#Override
public void initialize(URL url, ResourceBundle rb) {
// TODO
}
}
## FXMLDocument.fxml ##
<?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" prefWidth="320" xmlns:fx="http://javafx.com/fxml/1" fx:controller="javafxapplication2.FXMLDocumentController">
<children>
<Button layoutX="126" layoutY="90" text="Click Me!" onAction="#handleButtonAction" fx:id="button" />
<Label layoutX="126" layoutY="120" minHeight="16" minWidth="69" fx:id="label" />
</children>
I think that your problem is caused by private method "handleButtonAction". Turn it to public and try then. Greetings
I have an application that is designed to be a sandwich shop system and I have a main menu form that is my main class i.e. this class holds my main class and is the first form to open when the application is executed.
When I click on the create new standard order button I have it so it will display a menu of items to chose from. I have this code behind the create new standard order button so it will hide the first window and display the next window.
btnStdOrder.setOnAction(e -> {
((Node)e.getSource()).getScene().getWindow().hide();
NewOrderPopUp.Display();
});
However, how do I go back to this first window? I have tried using the same code as above but because the first form holds my main and start methods I cant recall them again using the above method (or maybe I can I just don't know how to do it). Any help would be greatly appreciated.
If your popUpDisplay method ends with showAndWait(), you can try this:
((Stage)((Node)e.getSource()).getScene().getWindow()).hide();
NewOrderPopUp.Display();
((Stage)((Node)e.getSource()).getScene().getWindow()).show();
I created a sample app that shows this behavior in action.
Main
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
/**
*
* #author blj0011
*/
public class JavaFXApplication53 extends Application
{
#Override
public void start(Stage stage) throws Exception
{
Parent root = FXMLLoader.load(getClass().getResource("FXMLDocument.fxml"));
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
/**
* #param args the command line arguments
*/
public static void main(String[] args)
{
launch(args);
}
}
Controller - MainScene
import java.io.*;
import java.net.URL;
import java.util.*;
import java.util.logging.*;
import javafx.fxml.*;
import javafx.scene.*;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.stage.*;
/**
*
* #author blj0011
*/
public class FXMLDocumentController implements Initializable
{
#FXML private Button btnMain;
Stage window;
#Override
public void initialize(URL url, ResourceBundle rb)
{
// TODO
btnMain.setOnAction(e -> {
((Stage)((Node)e.getSource()).getScene().getWindow()).hide();
popUpDisplay();
((Stage)((Node)e.getSource()).getScene().getWindow()).show();
});
}
public void popUpDisplay()
{
try
{
FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("SceneTwo.fxml"));
Parent root1 = (Parent) fxmlLoader.load();
Stage stage = new Stage();
stage.initModality(Modality.APPLICATION_MODAL);
//stage.initStyle(StageStyle.UNDECORATED);
stage.setTitle("PopUp");
stage.setScene(new Scene(root1));
stage.showAndWait();
}
catch (IOException ex)
{
Logger.getLogger(FXMLDocumentController.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
FXML - Main Scene
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.text.Font?>
<AnchorPane id="AnchorPane" maxHeight="300.0" maxWidth="300.0" minHeight="300.0" minWidth="300.0" prefHeight="300.0" prefWidth="300.0" xmlns="http://javafx.com/javafx/8.0.111" xmlns:fx="http://javafx.com/fxml/1" fx:controller="javafxapplication53.FXMLDocumentController">
<children>
<Button fx:id="btnMain" layoutX="124.0" layoutY="248.0" mnemonicParsing="false" text="Button" />
<Label layoutX="99.0" layoutY="135.0" text="Main Scene">
<font>
<Font size="20.0" />
</font>
</Label>
</children>
</AnchorPane>
Controller - PopUp
import java.net.URL;
import java.util.ResourceBundle;
import javafx.fxml.*;
import javafx.scene.*;
import javafx.scene.control.*;
import javafx.stage.*;
/**
* FXML Controller class
*
* #author blj0011
*/
public class SceneTwoController implements Initializable
{
#FXML Button btnClosePopup;
/**
* Initializes the controller class.
* #param url
* #param rb
*/
#Override
public void initialize(URL url, ResourceBundle rb)
{
// TODO
btnClosePopup.setOnAction(e -> {
((Stage)(((Button)e.getSource()).getScene().getWindow())).close();
});
}
}
FXML - PopUp
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.text.Font?>
<AnchorPane id="AnchorPane" prefHeight="400.0" prefWidth="600.0" xmlns:fx="http://javafx.com/fxml/1" xmlns="http://javafx.com/javafx/8.0.111" fx:controller="javafxapplication53.SceneTwoController">
<children>
<Label layoutX="257.0" layoutY="155.0" text="Popup">
<font>
<Font size="30.0" />
</font>
</Label>
<Button fx:id="btnClosePopup" layoutX="259.0" layoutY="353.0" mnemonicParsing="false" text="Close Popup" />
</children>
</AnchorPane>
I am learning to write FXML custom components for use with JavaFX 8 and Scene Builder.
I wrote the FXML file shown below but Scene Builder will not open it, giving me the message "Open operation has failed" due to the exception:
java.io.IOException: javafx.fxml.LoadException: mycustomcomponent.TicoTeco is not a valid type.
/C:/Users/xxxxx/Documents/NetBeansProjects/MyCustomComponent/src/mycustomcomponent/TicoTeco.fxml:9
at com.oracle.javafx.scenebuilder.kit.fxom.FXOMLoader.load(FXOMLoader.java:92)
at com.oracle.javafx.scenebuilder.kit.fxom.FXOMDocument.(FXOMDocument.java:80)
at com.oracle.javafx.scenebuilder.kit.fxom.FXOMDocument.(FXOMDocument.java:95)
...
Why am I getting this exception?
Here's the FXML file:
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<fx:root type="mycustomcomponent.TicoTeco" prefHeight="93.0" prefWidth="304.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1">
<children>
<BorderPane layoutX="61.0" prefHeight="115.0" prefWidth="200.0">
<left>
<Button fx:id="tico" mnemonicParsing="false" text="Tico" BorderPane.alignment="CENTER" />
</left>
<right>
<Button fx:id="teco" mnemonicParsing="false" text="Teco" BorderPane.alignment="CENTER" />
</right>
</BorderPane>
</children>
</fx:root>
And here are the Java files for TicoTeco.java and Main.java:
package mycustomcomponent;
import java.io.IOException;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.scene.control.Button;
import javafx.scene.layout.AnchorPane;
public class TicoTeco extends AnchorPane {
#FXML
Button tico;
#FXML
Button teco;
public TicoTeco() throws IOException {
FXMLLoader fxmlLoader = new FXMLLoader(TicoTeco.class.getResource("TicoTeco.fxml"));
fxmlLoader.setRoot(this);
fxmlLoader.setController(this);
fxmlLoader.load();
}
#FXML
public void initialize() {
final EventHandler<ActionEvent> onAction =
event -> System.out.println("Hi, I'm " + (event.getSource() == tico? "Tico" : "Teco") + "!");
tico.setOnAction(onAction);
teco.setOnAction(onAction);
}
}
package mycustomcomponent;
import java.io.IOException;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;
public class Main extends Application {
#Override
public void start(Stage primaryStage) throws IOException {
Scene scene = new Scene(new TicoTeco());
primaryStage.setTitle("Here are Tico and Teco!");
primaryStage.setScene(scene);
primaryStage.show();
}
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
}
It's a bit tricky. So your fxml have a little mistake:
Your custom class is extending AnchorPane, so this should be the root in your fxml:
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<fx:root type="AnchorPane" prefHeight="93.0" prefWidth="304.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1">
<children>
<BorderPane layoutX="61.0" prefHeight="115.0" prefWidth="200.0">
<left>
<Button fx:id="tico" mnemonicParsing="false" text="Tico" BorderPane.alignment="CENTER" />
</left>
<right>
<Button fx:id="teco" mnemonicParsing="false" text="Teco" BorderPane.alignment="CENTER" />
</right>
</BorderPane>
</children>
</fx:root>
After that, you have to make a jar of it, because you have a fxml and a java class. This is the tricky part in Netbeans, so follow up:
First: Create an own Library Project for the component that looks like this with your copied source files:
Second: Delete the copied Main (where the main method is in) file
Third: Do a "Clean and Build" at the project. The generated .jar file will be in the subfolder "dist" in your Project directory.
Fourth: Open Scene Builder and import your CustomComponent .jar file like this:
Now you are able to use the component as you want. But be aware of changes to the component are not dynamicaly refresh the imported jar, you have to do the whole thing again.
I am not sure how to or even if it is possible to select text fields in code. I could not find anything on the subject. If the is indeed a way to do so i have a template that could be modified to demonstrate how this could be done.
Here is the template/sample code:
Main class:
package application;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
public class Main extends Application {
public void start(Stage primaryStage) {
try {
Parent root = FXMLLoader.load(getClass().getResource("/fxml/Main.fxml"));
Scene scene = new Scene(root,600,400);
scene.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
primaryStage.setScene(scene);
primaryStage.setTitle("Test");
primaryStage.show();
} catch(Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
launch(args);
}
}
MainControl class:
package application;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;
public class MainControl implements Initializable {
#FXML
Button button;
#FXML
TextField field1;
#FXML
TextField field2;
boolean field1selected=true;
public void initialize(URL arg0, ResourceBundle arg1) {
}
public void switchTextFeild(ActionEvent event){
/*
The code for switch on witch TextField is selected would go here
*/
}
}
Main.fxml:
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.text.*?>
<?import javafx.scene.control.*?>
<?import java.lang.*?>
<?import javafx.scene.layout.*?>
<AnchorPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="application.MainControl">
<children>
<TextField fx:id="field1" layoutX="6.0" layoutY="2.0" prefHeight="394.0" prefWidth="149.0" />
<TextField fx:id="field2" layoutX="445.0" layoutY="2.0" prefHeight="394.0" prefWidth="149.0" />
<Button fx:id="button" layoutX="177.0" layoutY="14.0" mnemonicParsing="false" onAction="#switchTextFeild" prefHeight="95.0" prefWidth="239.0" text="Switch" textAlignment="CENTER" wrapText="true">
<font>
<Font size="24.0" />
</font>
</Button>
</children>
</AnchorPane>
You can use
field1.requestFocus();
in your initialize() method, so your TextField field1 will be focused after your app is started.
But notice, you have to wrap the requestFocus() call within a
Platform.runLater(new Runnable() {
#Override
public void run() {
field1.requestFocus();
}
});
because this should be done on the JavaFX Application Thread and not on the Launcher Thread, so if you would only call field1.requestFocus() this wont have any effect on our TextField.
This is very simple
filedname.requestFocus();
fieldname.selectAll();
you have to first get the focus then use selectAll()function . if you will not use requestFocus() function then selectAll() will not work
The solution is simple for classic java. You can use code below for select text in a textField without doubleclicking on it (no idea about javafx).
field1.requestFocus();
field1.setSelectionStart(0);
field1.setSelectionEnd(field1.getText().length());
I have this controller:
package cz.vutbr.feec.bmds.cv2;
import java.awt.Button;
import java.awt.TextField;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.scene.control.Slider;
public class TestGuiController {
private int buttonPressed = 0;
#FXML
private Button tlacitko;
#FXML
private TextField textovePole;
#FXML
private Slider slider;
public void buttonPressed(ActionEvent e) {
buttonPressed++;
textovePole.setText(Integer.toString(buttonPressed));
}
}
this fxml:
<?xml version="1.0" encoding="UTF-8"?>
<?import java.lang.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<?import javafx.scene.layout.BorderPane?>
<AnchorPane prefHeight="200.0" prefWidth="200.0" xmlns:fx="http://javafx.com/fxml" fx:controller="cz.vutbr.feec.bmds.cv2.TestGuiController">
<children>
<Button fx:id="tlacitko" layoutX="30.0" layoutY="40.0" mnemonicParsing="false" onTouchPressed="#buttonPressed" text="Button" />
<Slider fx:id="slider" layoutX="157.0" layoutY="17.0" orientation="VERTICAL" />
<TextField fx:id="textovePole" layoutX="14.0" layoutY="89.0" prefWidth="134.0" />
</children>
</AnchorPane>
and this is my main class:
package cz.vutbr.feec.bmds.cv2;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
public class Main extends Application {
#Override
public void start(Stage primaryStage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource("TestGui.fxml"));
primaryStage.setTitle("Titulek");
primaryStage.setScene(new Scene(root,300,275));
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
When I run this through ant I get message box with error (exception during running application). I tried simple fxml without controller and it works so I am guesing I do something wrong with controller. What I must change to have it working?
I must answer my own question. Problem was in TestGuiController where I used java.awt.Button and java.awt.TextField instead of javafx.scene.control.Button and javafx.scene.control.TextField.
I'm not 100% sure but try:
in FXML: Button: onAction instead of onTouchPressed
Please provide the exact Exception message.