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Elements not showing in GridBagLayout
(2 answers)
Closed 7 years ago.
So I'm trying to create my first GUI in Java but it's coming up blank. As far as I can see I've done everything correct, but of course since it's just blank I'm obviously doing something wrong.
I've got a mainclass and a class for the JFrame and all its contents.
I'm not getting any errors except for the public class MainFrame giving me "The serializable class MainFrame does not declare a static final serialVersionUID field of type long".
package main;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
import gui.MainFrame;
public class Main {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run()
MainFrame frame = new MainFrame();
frame.setTitle("GUI");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(800, 400);
frame.setVisible(true);
}
});
}
}
.
package gui;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class MainFrame extends JFrame {
private JButton button;
private Container cont;
public MainFrame(){
Container cont = new Container();
setLayout(new BorderLayout());
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
JButton button = new JButton("Change Color");
panel.add(button, BorderLayout.CENTER);
cont.add(panel, BorderLayout.CENTER);
cont.setBackground(Color.GREEN);
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
cont.setBackground(Color.CYAN);
}
});
}
}
You didn't add Container cont to the frame.
Forgot about adding component to frame:
panel.add(cont);
Related
I am new here and i want to ask, i just wanted to set new JLabel and i want it to put it to specific place. But it doesnt work. Im sorry if this is dumm question but i am begginer
:
package ChangingImageAtTheTop;
import java.awt.Color;
import java.awt.Font;
import javax.swing.*;
public class Gui {
public static void main(String[] args) {
guii f = new guii();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(500, 500);
f.setVisible(true);
}
}
package ChangingImageAtTheTop;
import javax.swing.*;
import java.awt.*;
public class guii extends JFrame {
public guii() {
super("c");
setLayout(new FlowLayout());
JLabel label = new JLabel();
label.setText("User");
label.setBounds(10,25,30,85);
add(label);
}
}
I want to be able to call the Introduction.Intro() method into my main file code, but it tells me I am unable to call a non-static method intro from a static context. Since I am still fairly new to coding I'm not entirely sure what the problem is. I've added my codes down below. I've tried countless online methods but sadly none have seemed to work.
import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BorderFactory;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Start extends JFrame implements ActionListener
{
private JFrame Main;
private JPanel PanelA, PanelB, PanelC;
private JLabel Text, ImageL;
private JButton Button;
private ImageIcon Image;
public Start ()
{
//Button
Button = new JButton("Start");
Button.addActionListener(new ButtonListener());
//Text
Text = new JLabel("Welcome To The Game"); //ADD NAME OF THE GAME
//Image
Image = new ImageIcon(getClass().getResource("download.jfif")); //ADD THE IMAGE FOR WELCOME
ImageL = new JLabel(Image);
//Top Panel (PanelA) - Image
PanelA = new JPanel();
PanelA.setBorder(BorderFactory.createEmptyBorder(0,200,150,200));
PanelA.setLayout(new FlowLayout(FlowLayout.CENTER));
PanelA.add(ImageL);
//Middle Panel (PanelB) - Text
PanelB = new JPanel();
PanelB.setBorder(BorderFactory.createEmptyBorder(50,200,10,200));
PanelB.setLayout(new FlowLayout(FlowLayout.CENTER));
PanelB.add(Text);
//Bottom Panel (PanelC) - Buttons
PanelC = new JPanel();
PanelC.setBorder(BorderFactory.createEmptyBorder(0,200,20,200));
PanelC.setLayout(new FlowLayout(FlowLayout.CENTER));
PanelC.add(Button);
//Main Frame
Main = new JFrame ();
Main.add(PanelA, BorderLayout.NORTH);
Main.add(PanelB, BorderLayout.CENTER);
Main.add(PanelC, BorderLayout.SOUTH);
Main.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Main.setTitle("GAME TITLE"); //ADD THIS LATER
Main.pack();
Main.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent ae)
{
}
public class ButtonListener implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
if(e.getSource() == Button)
{
Introduction.Intro1(); //THESE LINE RIGHT HERE
return null; //THESE LINE RIGHT HERE
}
}
}
public static void main(String[] args)
{
new Start();
}
}
import java.awt.BorderLayout;
import java.awt.FlowLayout;
import javax.swing.BorderFactory;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Introduction
{
private JFrame Main;
private JPanel PanelD;
private JLabel Text, ImageL;
private JButton Button;
private ImageIcon Image;
public void Intro()
{
Image = new ImageIcon(getClass().getResource("guy.jfif"));
ImageL = new JLabel(Image);
PanelD = new JPanel();
PanelD.setBorder(BorderFactory.createEmptyBorder(0,100,10,100));
PanelD.setLayout(new FlowLayout(FlowLayout.CENTER));
PanelD.add(ImageL);
PanelD.setVisible(true);
Main.add(PanelD, BorderLayout.NORTH);
}
}
EDIT: So I made another method in the Introduction class where I added this line of code, it managed to fix the error, however, the panel isn't being saved and my JFrame is outputting blank.
public static JFrame Intro1()
{
Introduction M = new Introduction();
return M;
}
If you are looking to initialize the Introduction class in main method of Start class, You can add belo code in main method after Start()
Introduction M = new Introduction();
You main method becomes :
public static void main(String[] args)
{
new Start();
Introduction M = new Introduction();
m.Intro
}
Looking at this set of code, It looks like there is incompatible issue, as you have declare JFrame as return type, while you are returning instance of Introduction.
public static JFrame Intro1()
{
Introduction M = new Introduction();
return M;
}
I'm a relatively young programmer and I'm having a problem. When ever I try to run my program on the custom JPanel I made doesn't show up most of the time and when it does show up it and I try to run it again with the exact same code it doesn't work.
Can someone please help me?
package ca.Software.PocketUniverse;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.net.*;
public class MercuryMain extends JFrame {
ImageIcon windowicon;
public MercuryMain(){
windowsetup();
}
public void windowsetup(){
JFrame j=new JFrame();
windowicon= new ImageIcon(getClass().getResource("mercury.jpg"));
this.setTitle("MercuryMessaging");
this.setVisible(true);
this.setResizable(false);
this.pack();
this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
this.setLocationRelativeTo(null);
this.setIconImage(windowicon.getImage());
ContentPanel p=new ContentPanel();
JButton b=new JButton("code");
p.add(b);
add(p);
}
public void errormethod(){
}
public static void main(String[] args) {
new MercuryMain();
}
}
ContentPanel
package ca.Software.PocketUniverse;
import javax.swing.JPanel;
import javax.swing.JButton;
import java.awt.BorderLayout;
import java.awt.CardLayout;
public class ContentPanel extends JPanel {
/**
*
*/
private static final long serialVersionUID = 1L;
JButton contacts;
public ContentPanel(){
setLayout(new BorderLayout());
contacts=new JButton("contacts");
this.add(contacts,BorderLayout.NORTH);
}
}
I have created a simple VLCJ project that consists of a simple embedded player and a button to exit.
The code is as follows:
package test;
import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.Color;
import java.awt.Frame;
import java.awt.Panel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import uk.co.caprica.vlcj.binding.LibVlc;
import uk.co.caprica.vlcj.component.EmbeddedMediaPlayerComponent;
import uk.co.caprica.vlcj.runtime.RuntimeUtil;
import com.sun.jna.Native;
import com.sun.jna.NativeLibrary;
public class Demo {
private final JFrame frame;
private final EmbeddedMediaPlayerComponent mediaPlayerComponent;
private JPanel videoPane;
private JPanel buttonPane;
private Button exitButton;
private ActionListener a;
private static String vlc_location = "C:\\Program Files\\VideoLAN\\VLC";
public static void main(String[] args) {
NativeLibrary.addSearchPath(RuntimeUtil.getLibVlcLibraryName(), vlc_location);
Native.loadLibrary(RuntimeUtil.getLibVlcLibraryName(), LibVlc.class);
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Demo().run();
}
});
}
public Demo() {
mediaPlayerComponent = new EmbeddedMediaPlayerComponent();
a = new MyActionListener();
exitButton = new Button("Exit");
exitButton.setActionCommand("Exit app");
exitButton.addActionListener(a);
buttonPane = new JPanel();
buttonPane.setLayout(new BorderLayout());
buttonPane.setBackground(Color.black);
buttonPane.add(exitButton, BorderLayout.CENTER);
videoPane = new JPanel();
videoPane.setLayout(new BorderLayout());
videoPane.setBackground(Color.black);
videoPane.add(mediaPlayerComponent, BorderLayout.CENTER);
videoPane.add(buttonPane, BorderLayout.PAGE_END);
frame = new JFrame("vlcj demo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocation(100, 100);
frame.setSize(1200, 800);
frame.setContentPane(videoPane);
frame.setVisible(true);
}
public void run() {
mediaPlayerComponent.getMediaPlayer().playMedia(video_file);
}
class MyActionListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent arg0) {
String s = arg0.getActionCommand();
if (s.equals("Exit")) {
System.exit(0);
}
}
}
}
The problem is that the button does show up but it cannot be clicked. When i removed the videoPane, it was back to clickable! Any ideas if I'm missing something?
I am using the version 2.1.0 for vlcj.
Thanks!
Thanks MadProgrammer for your advise. I went on to think about it and tried commenting away the line of code in run(). The JButton came back!
However, when i un-commented the code in run(), the JButton disappeared. I was thinking maybe the Swing runnable was causing issue with the creation of the JButton.
Hence, what i did was to comment away the whole Swing runnable and just use:
final Demo demo = new Demo();
demo.run();
The demo can now play video and display the Exit button, thanks!
I have a main application frame (MainFrame class). On actionperformed event of a JButton, a JPanel (MyJPanel class) is opened by placing it in JDialog. I am not extending JDialog to create MyJPanel class because I might need MyJPanel at other purposes too.
My Problem is I cannot programmatically close the MyJPanel which is displayed in JDialog. Is there anything that I missing? Could you please figure it out?
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.WindowConstants;
public class MainFrame extends JPanel {
public MainFrame() {
JButton btnOpenJdialog = new JButton("Open JDialog");
add(btnOpenJdialog);
btnOpenJdialog.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
JDialog jd = new JDialog();
MyJPanel mjp = new MyJPanel(true);//showing in JDialog
jd.setTitle("JDialog");
jd.add(mjp);
jd.pack();
jd.setVisible(true);
}
});
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
public static void createAndShowGUI() {
JFrame frame = new JFrame("Test-JFrame");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.getContentPane().add(new MainFrame());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
MyJPanel Class :
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JPanel;
import javax.swing.JButton;
public class MyJPanel extends JPanel {
private boolean isShownInJDialog = false;
public MyJPanel() {
JButton btnCloseMe = new JButton("Finish Action");
add(btnCloseMe);
btnCloseMe.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (isShownInJDialog) {
MyJPanel.this.setVisible(false);
//how to close the JDialog too.
}
else {
//just hide the content,
MyJPanel.this.setVisible(false);
}
}
});
}
public MyJPanel(boolean isShownInJDialog) {
this();
this.isShownInJDialog = isShownInJDialog;
}
}
UPDATE
I was able to solve this using Howard's answer as :
...
if (isShownInJDialog) {
Window w = SwingUtilities.getWindowAncestor(MyJPanel.this);
w.setVisible(false);
}
...
If I understand your question correctly, you want to close the JDialog which your MyJPanel is contained in but do not have a reference to it?
You may either provide such a reference using the constructor of MyJPanel or change the code inside your ActionListener to
Window w = SwingUtilities.getWindowAncestor(MyJPanel.this);
w.setVisible(false);
which looks up the parent window of your panel without direct reference.