Develop Reference

Bar Chart from different class in to GUI class

I have Gui class with a JPanel and JButton. When the button is clicked i would like to display the graph in my JPanel. The Graph is in different class. Can someone help me do this please?
GUI CLASS:
public class Gui extends JFrame implements ActionListener{
JButton showGraph;
public Gui() {
super("GUI");
setSize(1200,600);
setDefaultCloseOperation(EXIT_ON_CLOSE);
showGraph = new JButton("SHOW GRAPH");
JPanel mainPanel = new JPanel();
add(mainPanel);
mainPanel.setLayout(new GridLayout(2,0,10,10));
mainPanel.setBorder(new EmptyBorder(10,10,10,10));
mainPanel.add(showGraph);
JPanel graphPanel = new JPanel();
graphPanel.setBackground(Color.yellow);
mainPanel.add(graphPanel);
showGraph.addActionListener(this);
}
public static void main (String[] args){
new Gui().setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == showGraph) {
SimpleBarChart b = new SimpleBarChart();
b.getGraph();
}
}
}

Change your getGraph() method to take a JFrame and pass in this.
public void getgraph(JFrame f) {
//JFrame f = new JFrame();
f.setSize(400, 300);
... as before ...
}
Then call in actionPerformed
if (e.getSource() == showGraph) {
SimpleBarChart b = new SimpleBarChart();
b.getGraph(this);
}
You can't have a frame inside a frame. Another option would be to make getGraph() return a JPanel and then you could put the panel in your existing frame instead of updating the whole frame.

How do i add an action to a JFrame JButton?

I have a JFrame gui im making and I need help.
Im trying to find out how to add a action to my button.
as in using it in a "if" statement or make i print something out when you push it.
thanks!
code:
package agui;
import javax.swing.*;
public class Agui extends JFrame {
public Agui() {
setTitle("My Gui");
setSize(400, 400);
JButton button = new JButton("click me");
JPanel panel = new JPanel();
panel.add(button);
this.getContentPane().add(panel);
setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
public static void main(String[] args) {
Agui a = new Agui();
}
}

You want the "addActionListener" method, something like:
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.out.println("You clicked the button");
}
});

how to paint images on clicking button in frame?

I've made two buttons in frame .I want to know how to display different images on clicking different buttons?
is there another way out or i have to make panel?I am at beginner stage
package prac;
import java.awt.*;
import java.awt.event.*;
public class b extends Frame implements ActionListener{
String msg;
Button one,two;
b()
{ setSize(1000,500);
setVisible(true);
setLayout(new FlowLayout(FlowLayout.LEFT));
one=new Button("1");
two=new Button("2");
add(one);
add(two);
one.addActionListener(this);
two.addActionListener(this);
}
public void actionPerformed(ActionEvent e)
{
msg=e.getActionCommand();
if(msg.equals("1"))
{
msg="Pressed 1";
}
else
msg="pressed 2";
repaint();
}
public void paint(Graphics g)
{
g.drawString(msg,100,300);
}
public static void main(String s[])
{
new b();
}
}

Use JLabel and change the icon when button is clicked.
Some points:
call setVisible(true) in the end after adding all the component.
use JFrame#pack() method that automatically fit the components in the JFrame based on component's preferred dimension instead of calling JFrame#setSize() method.
sample code:
final JLabel jlabel = new JLabel();
add(jlabel);
final Image image1 = ImageIO.read(new File("resources/1.png"));
final Image image2 = ImageIO.read(new File("resources/2.png"));
JPanel panel = new JPanel();
JButton jbutton1 = new JButton("Show first image");
jbutton1.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
jlabel.setIcon(new ImageIcon(image1));
}
});
JButton jbutton2 = new JButton("Show second image");
jbutton2.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
jlabel.setIcon(new ImageIcon(image2));
}
});
panel.add(jbutton1);
panel.add(jbutton2);
add(panel, BorderLayout.NORTH);

Nothing happens when button is clicked

I'm writing a program in Java where I'm using JTabbedPane. Each tab is associated with a different panel with labels, textfields and a button. I have used GridBagLayout in the panels.
I have added an actionlistener to the button, but when I click it nothing happens.
EDIT: I also have other buttons outside the JTabbedPane which works perfectly fine.
I can see that nothing is happening because I do this:
public void actionPerformed( ActionEvent e ) {
if ( e.getSource() == button ) {
System.out.println("blablabla");
}
and nothing is printed out.
Is there any common problems with using buttons and GridBagLayout/JTabbedPane?
EDIT with SSCCE
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.*;
public class Hjelp extends JFrame {
private FlowLayout layout;
private JButton button1;
private JButton button2;
private JPanel menu, frontpage;
private JPanel present, previous, something;
public Hjelp() {
layout = new FlowLayout(FlowLayout.CENTER, 10, 20);
setLayout(layout);
setSize(900, 900);
setLocationRelativeTo(null);
setVisible(true);
setPanels();
something = something();
add(something, BorderLayout.CENTER);
something.setVisible(false);
button1 = new JButton("CLICK ME");
add(button1);
buttonListener();
}
private void buttonListener() {
Buttonlistener listener = new Buttonlistener();
button1.addActionListener(listener);
button2.addActionListener(listener);
}
private void setPanels() {
menu = new JPanel(new FlowLayout(FlowLayout.CENTER, 10, 0));
frontpage = new JPanel();
previous = frontpage;
present = frontpage;
add(menu);
}
public void visiblePanel() {
previous.setVisible(false);
present.setVisible(true);
}
private JPanel something() {
visiblePanel();
JPanel panel = new JPanel();
panel.setLayout(new GridLayout(1, 1));
JTabbedPane tabbedPane = new JTabbedPane();
JComponent panel1 = tab();
tabbedPane.addTab("Click me", panel1);
tabbedPane.setMnemonicAt(0, KeyEvent.VK_1);
tabbedPane.setTabLayoutPolicy(JTabbedPane.SCROLL_TAB_LAYOUT);
panel.add(tabbedPane);
return panel;
}
private JComponent tab() {
JPanel panel = new JPanel(false);
panel.setPreferredSize(new Dimension(870, 300));
panel.setLayout(new GridBagLayout());
GridBagConstraints cs = new GridBagConstraints();
cs.fill = GridBagConstraints.HORIZONTAL;
button2 = new JButton("Click me");
cs.gridx = 1;
cs.gridy = 6;
cs.gridwidth = 1;
panel.add(button2, cs);
return panel;
}
private class Buttonlistener implements ActionListener {
#Override
public void actionPerformed( ActionEvent e ) {
if ( e.getSource() == button1 ) {
present = something;
button1.setVisible(false);
something();
previous = something;
}
else if (e.getSource() == button2) {
System.out.println("Blablabla");
}
}
}
public static void main(String [] args) {
final Hjelp vindu = new Hjelp();
vindu.addWindowListener(
new WindowAdapter() {
#Override
public void windowClosing(WindowEvent e) {
System.exit(0);
}
} );
}
}
SOLVED
Solution

You don't need the getSource check at all—your listener is (hopefully) attached to just one button, so if it was invoked, that already means the button was clicked. Remove the check and unconditionally print your string. If you still don't see anything, then you have a problem.

You may not have attached a handler to the actual button, and therefore the event will never get called.
Part 1:
ButtonHandler handler = new ButtonHandler();
button.addActionListener( handler );
Part 2:
public class ButtonHandler implements ActionListener
{
#Override
public void actionPerformed(ActionEvent event) {
}
}
ALSO: Java GUI can be finicky, rather than using "e.getSource() == button" you could try "button..isFocusOwner()"

How to add JPanel by clicking JButton?

I'm trying to create a small GUI, it has 2 JButtons, and 2 JPanels with some drawing animation on each of them. By default it must show first JPanel, and by clicking on second JButton I want to see my second JPanel. So : I create JFrame, Panel1 and Panel2, where I have drawn my animations, create Button1 and Button2 and adding to them ActionListeners. I have also MainPanel which has in a fields variable i. By changing this "i" my constructor adds to MainPanel either Panel1 (default) or Panel2 (by clicking on JButton2 I change i). Than I add this MainPanel to my frame. So my question : in the class MainPanel I have refreshMe method, what should I write there to make my GUI working properly? Thanks. Here is my code:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class GuiTest {
public static void main(String[] args) {
JFrame f = new JFrame();
MainPanel myPanel = new MainPanel();
f.add(myPanel);
Button1 button1 = new Button1();
Button2 button2 = new Button2();
myPanel.add(button1);
myPanel.add(button2);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.pack();
f.setVisible(true);
}
}
class MainPanel extends JPanel {
Panel1 p1 = new Panel1();
Panel2 p2 = new Panel2();
public int i = 1; //this is being changed later by clicking JButton
// I use this setter later in actionPerformed in order to change i
public void setI(int i) {
this.i = i;
}
MainPanel() {
if (i == 1) {
this.add(p1);
}
if (i == 2) {
this.add(p2);
}
}
public void refreshMe() {
// Need some help here:
// I don't know what should I write, how to make a repaint of myPanel?
System.out.println("just test, if the method refreshMe working by clicking some button");
}
}
class Panel1 extends JPanel {
public Panel1() {
this.setBackground(Color.BLUE);
// a lot of drawing stuff going on here
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
class Panel2 extends JPanel {
public Panel2() {
this.setBackground(Color.GREEN);
// a lot of drawing stuff going on here
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
class Button1 extends JButton {
MainPanel someObj1 = new MainPanel();
Button1() {
setText("Show Annimation A");
addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
someObj1.setI(1);
System.out.println("The variable i is now: " + someObj1.i);
someObj1.refreshMe();
}
});
}
}
class Button2 extends JButton {
MainPanel someObj2 = new MainPanel();
Button2() {
setText("Show Annimation B");
addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
someObj2.setI(2);
System.out.println("The variable i is now: " + someObj2.i);
someObj2.refreshMe();
}
});
}
}

In order to reflect changes after adding/removing or resizing a component that is on a visible container call revalidate() and repaint() on the containers instance after adding/removing or resizing the component.
Though this will not work in your code the main reason being inside JButton classes you recreate a new instance of MainPanel when in fact the 2 JButtons should share the single instance which is being used (you could pass MainPanel instance to the JButtons constructors, but you shouldn't really be extending a JButton unless adding custom functionality):
class Button2 extends JButton {
MainPanel someObj2 = new MainPanel();//you create an instance of MainPanel which isnt even showing and than do changes on that, this way you will never see any of the changes
Button2() {
}
}
A few other suggestions on your code:
Dont extend JButton class unnecessarily, simply create an instance of JButton like you did with JFrame and call methods on JButton instance.
Dont forget to create/manipulate Swing components on Event Dispatch Thread, via SwingUtilities.invokeLater(..) block, read here for more.
Here is your code fixed (above suggestions ect implemented):
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Test {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame f = new JFrame();
final MainPanel myPanel = new MainPanel();
f.add(myPanel);
JButton button1 = new JButton("Show Animation A");
JButton button2 = new JButton("Show Animation B");
button1.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
myPanel.setI(1);
System.out.println("The variable i is now: " + myPanel.i);
myPanel.refreshMe();
}
});
button2.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
myPanel.setI(2);
System.out.println("The variable i is now: " + myPanel.i);
myPanel.refreshMe();
}
});
myPanel.add(button1);
myPanel.add(button2);
myPanel.checkPanel();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.pack();
f.setVisible(true);
}
});
}
}
class MainPanel extends JPanel {
Panel1 p1 = new Panel1();
Panel2 p2 = new Panel2();
public int i = 1; //this is being changed later by clicking JButton
// I use this setter later in actionPerformed in order to change i
public void setI(int i) {
this.i = i;
}
public void refreshMe() {
checkPanel();
revalidate();
repaint();
// Need some help here:
// I don't know what should I write, how to make a repaint of myPanel?
System.out.println("just test, if the method refreshMe working by clicking some button");
}
public void checkPanel() {
if (i == 1) {
this.add(p1);
this.remove(p2);//or it will remain there as this is default flowlayout
} else if (i == 2) {
this.add(p2);
this.remove(p1);
}
}
}
class Panel1 extends JPanel {
public Panel1() {
this.setBackground(Color.BLUE);
// a lot of drawing stuff going on here
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
class Panel2 extends JPanel {
public Panel2() {
this.setBackground(Color.GREEN);
// a lot of drawing stuff going on here
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
However Id suggest something simpler, fortunately you have 2 choices:
1) Use CardLayout which will allow you to flip between multiple components on a single JFrame/container.
Here is an example I made:
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Test {
private final static String PANEL1 = "panel 1";
private final static String PANEL2 = "panel 2";
public Test() {
initComponents();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Test();
}
});
}
private void initComponents() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel1 = new JPanel();
panel1.add(new JLabel("Panel 1"));
JPanel panel2 = new JPanel();
panel2.add(new JLabel("Panel 2"));
//Create the panel that contains the "cards".
final JPanel cards = new JPanel(new CardLayout());
cards.add(panel1, PANEL1);
cards.add(panel2, PANEL2);
//create button to allow chnage to next card
JButton buttonNext = new JButton(">");
buttonNext.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
CardLayout cl = (CardLayout) (cards.getLayout());//get cards
cl.next(cards);
}
});
//create button to allow chnage to previous card
JButton buttonPrev = new JButton("<");
buttonPrev.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
CardLayout cl = (CardLayout) (cards.getLayout());//get cards
cl.previous(cards);
}
});
//create panel to hold buttons which will allow switching between cards
JPanel buttonPanel = new JPanel();
buttonPanel.add(buttonPrev);
buttonPanel.add(buttonNext);
frame.add(cards);
frame.add(buttonPanel, BorderLayout.SOUTH);
frame.pack();
frame.setVisible(true);
}
}
2) Use removeAll() technique i.e call frame.getContentPane().removeAll() which will remove all components currently on JFrame and than add the new content and call revalidate() and repaint() (also might want to add pack() in there) on JFrame instance to reflect changes. Though Id recommend CardLayout.

I think you can just use CardLayout to implement your function. Please refer to here