Using a thread to repaint() components - java

It doesn't appear that my thread ever starts. Either that or the run method isn't actually doing anything, for which reason I could not explain.
I have a listener on my button StartRace and it should start the thread which will increment the length of each rectangle until one of them is long enough to be declared winner (by surpassing the width of the window, 250px).
I get all of the components initially painted to the screen, but they're never repainted. Is there something wrong with the way I call the method? Do I have classes nested within others that shouldn't be?
//--------------------------------------------------------------
// Start a race between blue and red, track the winner
// Use threads to manage each rectangle's movement
// Allow for user interaction, like stopping and starting
//--------------------------------------------------------------
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.Random;
public class ConcurrencyRace extends JFrame
{
private ConcurrencyPanel panel = new ConcurrencyPanel();
private JButton startRace = new JButton("Start The Race!");
private JButton stopRace = new JButton("Stop The Race!");
private JLabel winnerText = new JLabel("Winner: ");
private int blueDraw = 5, redDraw = 5;
private Random rn = new Random();
//-----------------------------------------------------------------
// Creates and displays the main program frame.
//-----------------------------------------------------------------
public ConcurrencyRace() {
super("Concurrency");
setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
Container cp = getContentPane();
cp.add(panel, BorderLayout.CENTER);
JPanel p = new JPanel();
p.add(startRace);
p.add(stopRace);
cp.add(p, BorderLayout.NORTH);
cp.add(winnerText, BorderLayout.SOUTH);
pack();
setVisible(true);
}
public static void main (String[] args)
{
ConcurrencyRace tRun = new ConcurrencyRace();
tRun.setVisible(true);
}
private class ConcurrencyPanel extends JPanel
{
public class runnerThread extends Thread {
#Override
public void run() {
while (blueDraw < 250 && redDraw < 250) {
panel.validate();
panel.repaint();
try {
Thread.sleep(200);
} catch (InterruptedException e) {}
}
}
}
public ConcurrencyPanel ()
{
setPreferredSize(new Dimension(600,250));
}
private class ButtonListener implements ActionListener {
runnerThread rectDraw = new runnerThread();
//--------------------------------------------------------------
// Starts the thread to draw each rectangle ("racer")
//--------------------------------------------------------------
public void actionPerformed (ActionEvent event)
{
if (event.getSource() == startRace) {
rectDraw.start();
}
}
}
#Override
public void paintComponent (Graphics page) {
super.paintComponent(page);
page.setColor(Color.blue);
page.fillRect(0,80,blueDraw,20);
page.setColor(Color.red);
page.fillRect(0,120,redDraw,20);
blueDraw += rn.nextInt(10) + 1;
redDraw += rn.nextInt(10) + 1;
page.dispose();
}
}
}

Primarily
You never add a ActionListener to either of your buttons, so nothing is responding when they are activated
Additionally
The state management is all over the place. blueDraw and redDraw should be instance fields of ConcurrencyPanel.
Don't update the state of the UI (or variables which the UI relies on) from within any paint method. Paint methods should paint the state, not change it. Updating the blueDraw and redDraw should be done in a specific method, which can be called when a update is required.
All of that leads me to believe you'd be better of using a Swing Timer
Conceptually...
You could do something like this...
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
public class ConcurrencyRace {
//-----------------------------------------------------------------
// Creates and displays the main program frame.
//-----------------------------------------------------------------
public ConcurrencyRace() {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
Timer timer = new Timer(200, null);
JFrame frame = new JFrame();
frame.add(new ButtonPane(timer), BorderLayout.NORTH);
frame.add(new RacePane(timer));
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public static void main(String[] args) {
new ConcurrencyRace();
}
public class ButtonPane extends JPanel {
private JButton startRace = new JButton("Start The Race!");
private JButton stopRace = new JButton("Stop The Race!");
public ButtonPane(Timer timer) {
startRace.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
timer.start();
}
});
stopRace.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
timer.stop();
}
});
setLayout(new GridBagLayout());
add(startRace);
add(stopRace);
}
}
private class RacePane extends JPanel {
private int blueDraw = 5, redDraw = 5;
private Random rn = new Random();
public RacePane(Timer timer) {
timer.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (updateState()) {
((Timer)e.getSource()).stop();
}
}
});
}
protected boolean updateState() {
blueDraw += rn.nextInt(10) + 1;
redDraw += rn.nextInt(10) + 1;
repaint();
return blueDraw >= getWidth() || redDraw >= getWidth();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(600, 250);
}
#Override
public void paintComponent(Graphics page) {
System.out.println(">>");
super.paintComponent(page);
page.setColor(Color.blue);
page.fillRect(0, 80, blueDraw, 20);
page.setColor(Color.red);
page.fillRect(0, 120, redDraw, 20);
}
}
}
This maintains the Timer as the central concept, which is shared between the buttons and race panels.
I've not added support for generating notification of a winner, this would be done via a simple observer pattern passed to the RacePane

Related

JPanel.remove not working with JButton actionListener? [duplicate]

The idea is to have one "global" JFrame which I can then add/remove JPanels as needed to make a smooth flowing application. Currently, when I try changing from the first JPanel to the second, the second won't display. My code is below:
Handler (class to run the app):
package com.example.Startup;
import com.example.Global.Global_Frame;
public class Handler
{
public Handler()
{
gf = new Global_Frame();
gf.getAccNum();
gf.setVisible(true);
}
public static void main(String[] args)
{
new Handler();
}
Global_Frame gf = null;
}
public static void main(String[] args)
{
new Handler();
}
Global_Vars gv = null;
Global_Frame gf = null;
}
Global Frame:
package com.example.Global;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JFrame;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import com.example.FirstRun.AccDetails;
import com.example.FirstRun.FirstTimeRun;
public class Global_Frame extends JFrame
{
private static final long serialVersionUID = 1L;
ActionListener val = new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
getUserDetails();
}
};
public Global_Frame()
{
try
{
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); // get look and feel based on OS
}
catch (ClassNotFoundException ex) // catch all errors that may occur
{
Logger.getLogger(Global_Frame.class.getName()).log(Level.SEVERE, null, ex);
}
catch (InstantiationException ex)
{
Logger.getLogger(Global_Frame.class.getName()).log(Level.SEVERE, null, ex);
}
catch (IllegalAccessException ex)
{
Logger.getLogger(Global_Frame.class.getName()).log(Level.SEVERE, null, ex);
}
catch (UnsupportedLookAndFeelException ex)
{
Logger.getLogger(Global_Frame.class.getName()).log(Level.SEVERE, null, ex);
}
EventQueue.invokeLater(new Runnable()
{
public void run() //run the class's constructor, therefore starting the UI being built
{
initComponents();
}
});
}
public void initComponents()
{
setPreferredSize(new Dimension(600, 400)); // setting measurements of jframe
revalidate(); // revalidate the elements that will be displayed
repaint(); // repainting what is displayed if going coming from a different form
pack(); // packaging everything up to use
setLocationRelativeTo(null); // setting form position central
}
public void getAccNum()
{
setPreferredSize(new Dimension(600, 400)); // setting measurements of jframe
FirstTimeRun panel1 = new FirstTimeRun(val);
add(panel1);
revalidate();
repaint();
pack();
}
public void getUserDetails()
{
getContentPane().removeAll();
resizing(750, 500);
AccDetails panel2 = new AccDetails();
add(panel2);
revalidate();
repaint();
pack();
}
private void resizing(int width, int height)
{
timer = new Timer (10, new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0)
{
getContentPane().removeAll();
setPreferredSize(new Dimension(sizeW, sizeH));
revalidate();
repaint();
pack();
if (!wToggle)
sizeW += 2;
if (!hToggle)
sizeH += 2;
if (toggle)
{
setLocationRelativeTo(null);
toggle = false;
}
else
toggle = true;
if (sizeW == width)
wToggle = true;
if (sizeH == height)
hToggle = true;
if (hToggle && wToggle)
timer.stop();
}
});
timer.start();
}
//variables used for window resizing
private Timer timer;
private int sizeW = 600;
private int sizeH = 400;
private boolean toggle = false;
private boolean wToggle = false;
private boolean hToggle = false;
public int accNum = 0;
}
First Panel:
package com.example.FirstRun;
import java.awt.Dimension;
import java.awt.event.ActionListener;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JPanel;
public class FirstTimeRun extends JPanel
{
private static final long serialVersionUID = 1L;
public FirstTimeRun()
{
}
public FirstTimeRun(ActionListener val)
{
initComponents(val);
}
private void initComponents(ActionListener val) // method to build initial view for user for installation
{
pnlStart = new JPanel[1];
btnNext = new JButton();
pnlStart[0] = new JPanel();
btnNext.setText("Next"); // adding text to button for starting
btnNext.setPreferredSize(new Dimension(80, 35)); //positioning start button
btnNext.addActionListener(val);
pnlStart[0].add(btnNext); // adding button to JFrame
setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
add(pnlStart[0]);
}
// objects used in UI
private JPanel[] pnlStart;
private JButton btnNext;
}
Second Panel:
package com.example.FirstRun;
import java.awt.BorderLayout;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class AccDetails extends JPanel
{
private static final long serialVersionUID = 1L;
public AccDetails()
{
accAssets();
}
private void accAssets()
{
// instantiating elements of the GUI
pnlAccDetails = new JPanel[2];
lblWelcome = new JLabel();
lblMain = new JLabel();
for (int i = 0; i < 2; i++)
pnlAccDetails[i] = new JPanel();
lblWelcome.setText("Welcome to Example_App"); // label welcoming user
pnlAccDetails[0].setLayout(new BoxLayout(pnlAccDetails[0], BoxLayout.LINE_AXIS));
pnlAccDetails[0].add(lblWelcome); // adding label to form
lblMain.setText("<html>The following information that is collected will be used as part of the Example_App process to ensure that each user has unique Example_App paths. Please fill in all areas of the following tabs:</html>"); // main label that explains what happens, html used for formatting
pnlAccDetails[1].setLayout(new BorderLayout());
pnlAccDetails[1].add(Box.createHorizontalStrut(20), BorderLayout.LINE_START);
pnlAccDetails[1].add(lblMain, BorderLayout.CENTER); //adding label to JFrame
pnlAccDetails[1].add(Box.createHorizontalStrut(20), BorderLayout.LINE_END);
setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
add(pnlAccDetails[0]);
add(pnlAccDetails[1]);
}
private JLabel lblWelcome;
private JLabel lblMain;
private JPanel[] pnlAccDetails;
}
I have tried using both a CardLayout and the "revalidate();" "repaint();" and "pack();" options and I'm stumped as to why it's not showing. Thanks in advance for any help that can be offered.
EDIT:
While cutting down my code, if the "resizing" method is removed, the objects are shown when the panels change. I would like to avoid having to remove this completely as it's a smooth transition for changing the JFrame size.
#John smith it is basic example of switch from one panel to other panel I hope this will help you to sort out your problem
Code:
package stack;
import java.awt.BorderLayout;
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.JLabel;
import javax.swing.JPanel;
public class RemoveAndAddPanel implements ActionListener{
JFrame frame;
JPanel firstPanel;
JPanel secondPanel;
JPanel controlPanel;
JButton nextButton;
public RemoveAndAddPanel() {
JFrame.setDefaultLookAndFeelDecorated(true);
frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
firstPanel = new JPanel();
firstPanel.add(new JLabel("FirstPanel"));
firstPanel.setPreferredSize(new Dimension(100,100));
secondPanel = new JPanel();
secondPanel.add(new JLabel("Second panel"));
secondPanel.setPreferredSize(new Dimension(100,100));
nextButton = new JButton("Next panel");
controlPanel = new JPanel();
nextButton.addActionListener(this);
controlPanel.add(nextButton);
frame.setLayout(new BorderLayout());
frame.add(firstPanel,BorderLayout.CENTER);
frame.add(controlPanel, BorderLayout.SOUTH);
frame.setVisible(true);
frame.setSize(300,100);
}
#Override
public void actionPerformed(ActionEvent e) {
if(e.getSource() == nextButton) {
frame.remove(firstPanel);
frame.add(secondPanel);
nextButton.setEnabled(false);
}
frame.validate();
}
public static void main(String args[]) {
new RemoveAndAddPanel();
}
}
As mentioned in the edit, the problem lay within the resizing method. When the timer stopped, it wouldn't go anywhere, causing the UI to not load. The fix to the code is clearing the screen and adding the call to resizing to the actionlistener. Then adding a call to the next method after:
timer.stop();
Thanks for getting me to remove the mess around it and find the source of the problem #matt & #Hovercraft Full of Eels upvotes for both of you.
The main thing to consider while changing panel in a jframe is the layout, for a body(main) panel to change to any other panel the parent panel must be of type CardLayout body.setLayout(new java.awt.CardLayout());
After that you can now easily switch between panels wiht the sample code below
private void updateViewLayout(final HomeUI UI, final JPanel paneeelee){
final JPanel body = UI.getBody(); //this is the JFrame body panel and must be of type cardLayout
System.out.println("Page Loader Changing View");
new SwingWorker<Object, Object>() {
#Override
protected Object doInBackground() throws Exception {
body.removeAll();//remove all visible panel before
body.add(paneeelee);
body.revalidate();
body.repaint();
return null;
}
#Override
protected void done() {
UI.getLoader().setVisible(false);
}
}.execute();
}

Prevent JButton repaint() after click

I have a button. I want to change the background after I click on it. My problem here is the button auto call paintComponent(). How can prevent this? I expect after clicking the button the button will be blue, but it will still be red.
package test;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class ButtonDemo extends JButton implements ActionListener{
public ButtonDemo() {
this.setText("BUTTON TEXT");
this.addActionListener(this);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
setBackground(Color.RED);
}
public static void main(String[] args){
JFrame frame = new JFrame();
JPanel contentPane = new JPanel();
frame.setContentPane(contentPane);
contentPane.add(new ButtonDemo());
frame.setSize(500, 500);
frame.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
this.setBackground(Color.BLUE);
}
}
My personal gut feeling is that JButton is probably not suited to your desired goal.
Essentially, you want to control when and how the "selected" state of the piece is changed.
Personally, I would have some kind of controller which monitored the mouse events in some way (probably having the piece component delegate the event back to the controller) and some kind of model which control when pieces become selected, this would then notify the controller of the state change and it would make appropriate updates to the UI.
But that's a long process to setup. Instead, I'm demonstrating a simple concept where a component can be selected with the mouse, but only the controller can de-select. In this example, this will allow only a single piece to be selected
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.LineBorder;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
public class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setLayout(new GridLayout(5, 5));
ChangeListener listener = new ChangeListener() {
private PiecePane selectedPiece;
#Override
public void stateChanged(ChangeEvent e) {
if (!(e.getSource() instanceof PiecePane)) { return; }
PiecePane piece = (PiecePane) e.getSource();
// Want to ignore events from the selected piece, as this
// might interfer with the changing of the pieces
if (selectedPiece == piece) { return; }
if (selectedPiece != null) {
selectedPiece.setSelecetd(false);
selectedPiece = null;
}
selectedPiece = piece;
}
};
for (int index = 0; index < 5 * 5; index++) {
PiecePane pane = new PiecePane();
pane.addChangeListener(listener);
add(pane);
}
}
}
public class PiecePane extends JPanel {
private boolean selecetd;
private Color selectedBackground;
private Color normalBackground;
private MouseListener mouseListener;
public PiecePane() {
setBorder(new LineBorder(Color.DARK_GRAY));
mouseListener = new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
setSelecetd(true);
}
};
setNormalBackground(Color.BLUE);
setSelectedBackground(Color.RED);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(50, 50);
}
#Override
public void addNotify() {
super.addNotify();
addMouseListener(mouseListener);
}
#Override
public void removeNotify() {
super.removeNotify();
removeMouseListener(mouseListener);
}
public void addChangeListener(ChangeListener listener) {
listenerList.add(ChangeListener.class, listener);
}
public void removeChangeListener(ChangeListener listener) {
listenerList.remove(ChangeListener.class, listener);
}
protected void fireSelectionChanged() {
ChangeListener[] listeners = listenerList.getListeners(ChangeListener.class);
if (listeners.length == 0) {
return;
}
ChangeEvent evt = new ChangeEvent(this);
for (int index = listeners.length - 1; index >= 0; index--) {
listeners[index].stateChanged(evt);
}
}
public boolean isSelected() {
return selecetd;
}
public void setSelecetd(boolean selecetd) {
if (selecetd == this.selecetd) { return; }
this.selecetd = selecetd;
updateSelectedState();
fireSelectionChanged();
}
public Color getSelectedBackground() {
return selectedBackground;
}
public void setSelectedBackground(Color selectedBackground) {
this.selectedBackground = selectedBackground;
updateSelectedState();
}
public Color getNormalBackground() {
return normalBackground;
}
public void setNormalBackground(Color normalBackground) {
this.normalBackground = normalBackground;
updateSelectedState();
}
protected void updateSelectedState() {
if (isSelected()) {
setBackground(getSelectedBackground());
} else {
setBackground(getNormalBackground());
}
}
}
}
I created a toggle button.
You set the primary color and the alternate color in the class constructor.
When you call the switchColors method, the JButton background changes from the primary color to the alternate color. When you call the switchColors method again, the JButton background changes from the alternate color to the primary color.
In the following example, I put the switchColors method in the actionListener so you can see the color change. Each time you left-click on the JButton, the background color changes.
You would call the switchColors method when you want the JButton background to change from blue to red, and again when you want the JButton background to change from red to blue. It's under your control.
import java.awt.BorderLayout;
import java.awt.Color;
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 ButtonDemo extends JButton
implements ActionListener {
private static final long serialVersionUID = 1L;
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame("Button Demo");
frame.setDefaultCloseOperation(
JFrame.EXIT_ON_CLOSE);
JPanel contentPane = new JPanel();
contentPane.setLayout(new BorderLayout());
frame.setContentPane(contentPane);
contentPane.add(new ButtonDemo(Color.BLUE,
Color.RED));
frame.setSize(300, 300);
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
});
}
private boolean primaryBackground;
private Color primaryColor;
private Color alternateColor;
public ButtonDemo(Color primaryColor,
Color alternateColor) {
this.primaryColor = primaryColor;
this.alternateColor = alternateColor;
this.primaryBackground = true;
this.setText("BUTTON TEXT");
this.setBackground(primaryColor);
this.addActionListener(this);
}
public void switchColors() {
primaryBackground = !primaryBackground;
Color color = primaryBackground ? primaryColor :
alternateColor;
this.setBackground(color);
}
#Override
public void actionPerformed(ActionEvent e) {
switchColors();
}
}
If you want to change the background for a short while you can do it with swing Timer:
import java.awt.Color;
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.Timer;
public class ButtonDemo extends JButton implements ActionListener{
private static final int DELAY = 600; //milliseconds
private final Timer timer;
public ButtonDemo() {
this.setText("BUTTON TEXT");
this.addActionListener(this);
Color defaultCloor = getBackground();
timer = new Timer(DELAY, e-> setBackground(defaultCloor));
timer.setRepeats(false);
}
public static void main(String[] args){
JFrame frame = new JFrame();
JPanel contentPane = new JPanel();
frame.setContentPane(contentPane);
contentPane.add(new ButtonDemo());
frame.setSize(300, 200);
frame.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
timer.stop();
this.setBackground(Color.RED);
timer.start();
}
}

JPanel not changing on JFrame

The idea is to have one "global" JFrame which I can then add/remove JPanels as needed to make a smooth flowing application. Currently, when I try changing from the first JPanel to the second, the second won't display. My code is below:
Handler (class to run the app):
package com.example.Startup;
import com.example.Global.Global_Frame;
public class Handler
{
public Handler()
{
gf = new Global_Frame();
gf.getAccNum();
gf.setVisible(true);
}
public static void main(String[] args)
{
new Handler();
}
Global_Frame gf = null;
}
public static void main(String[] args)
{
new Handler();
}
Global_Vars gv = null;
Global_Frame gf = null;
}
Global Frame:
package com.example.Global;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JFrame;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import com.example.FirstRun.AccDetails;
import com.example.FirstRun.FirstTimeRun;
public class Global_Frame extends JFrame
{
private static final long serialVersionUID = 1L;
ActionListener val = new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
getUserDetails();
}
};
public Global_Frame()
{
try
{
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); // get look and feel based on OS
}
catch (ClassNotFoundException ex) // catch all errors that may occur
{
Logger.getLogger(Global_Frame.class.getName()).log(Level.SEVERE, null, ex);
}
catch (InstantiationException ex)
{
Logger.getLogger(Global_Frame.class.getName()).log(Level.SEVERE, null, ex);
}
catch (IllegalAccessException ex)
{
Logger.getLogger(Global_Frame.class.getName()).log(Level.SEVERE, null, ex);
}
catch (UnsupportedLookAndFeelException ex)
{
Logger.getLogger(Global_Frame.class.getName()).log(Level.SEVERE, null, ex);
}
EventQueue.invokeLater(new Runnable()
{
public void run() //run the class's constructor, therefore starting the UI being built
{
initComponents();
}
});
}
public void initComponents()
{
setPreferredSize(new Dimension(600, 400)); // setting measurements of jframe
revalidate(); // revalidate the elements that will be displayed
repaint(); // repainting what is displayed if going coming from a different form
pack(); // packaging everything up to use
setLocationRelativeTo(null); // setting form position central
}
public void getAccNum()
{
setPreferredSize(new Dimension(600, 400)); // setting measurements of jframe
FirstTimeRun panel1 = new FirstTimeRun(val);
add(panel1);
revalidate();
repaint();
pack();
}
public void getUserDetails()
{
getContentPane().removeAll();
resizing(750, 500);
AccDetails panel2 = new AccDetails();
add(panel2);
revalidate();
repaint();
pack();
}
private void resizing(int width, int height)
{
timer = new Timer (10, new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0)
{
getContentPane().removeAll();
setPreferredSize(new Dimension(sizeW, sizeH));
revalidate();
repaint();
pack();
if (!wToggle)
sizeW += 2;
if (!hToggle)
sizeH += 2;
if (toggle)
{
setLocationRelativeTo(null);
toggle = false;
}
else
toggle = true;
if (sizeW == width)
wToggle = true;
if (sizeH == height)
hToggle = true;
if (hToggle && wToggle)
timer.stop();
}
});
timer.start();
}
//variables used for window resizing
private Timer timer;
private int sizeW = 600;
private int sizeH = 400;
private boolean toggle = false;
private boolean wToggle = false;
private boolean hToggle = false;
public int accNum = 0;
}
First Panel:
package com.example.FirstRun;
import java.awt.Dimension;
import java.awt.event.ActionListener;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JPanel;
public class FirstTimeRun extends JPanel
{
private static final long serialVersionUID = 1L;
public FirstTimeRun()
{
}
public FirstTimeRun(ActionListener val)
{
initComponents(val);
}
private void initComponents(ActionListener val) // method to build initial view for user for installation
{
pnlStart = new JPanel[1];
btnNext = new JButton();
pnlStart[0] = new JPanel();
btnNext.setText("Next"); // adding text to button for starting
btnNext.setPreferredSize(new Dimension(80, 35)); //positioning start button
btnNext.addActionListener(val);
pnlStart[0].add(btnNext); // adding button to JFrame
setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
add(pnlStart[0]);
}
// objects used in UI
private JPanel[] pnlStart;
private JButton btnNext;
}
Second Panel:
package com.example.FirstRun;
import java.awt.BorderLayout;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class AccDetails extends JPanel
{
private static final long serialVersionUID = 1L;
public AccDetails()
{
accAssets();
}
private void accAssets()
{
// instantiating elements of the GUI
pnlAccDetails = new JPanel[2];
lblWelcome = new JLabel();
lblMain = new JLabel();
for (int i = 0; i < 2; i++)
pnlAccDetails[i] = new JPanel();
lblWelcome.setText("Welcome to Example_App"); // label welcoming user
pnlAccDetails[0].setLayout(new BoxLayout(pnlAccDetails[0], BoxLayout.LINE_AXIS));
pnlAccDetails[0].add(lblWelcome); // adding label to form
lblMain.setText("<html>The following information that is collected will be used as part of the Example_App process to ensure that each user has unique Example_App paths. Please fill in all areas of the following tabs:</html>"); // main label that explains what happens, html used for formatting
pnlAccDetails[1].setLayout(new BorderLayout());
pnlAccDetails[1].add(Box.createHorizontalStrut(20), BorderLayout.LINE_START);
pnlAccDetails[1].add(lblMain, BorderLayout.CENTER); //adding label to JFrame
pnlAccDetails[1].add(Box.createHorizontalStrut(20), BorderLayout.LINE_END);
setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
add(pnlAccDetails[0]);
add(pnlAccDetails[1]);
}
private JLabel lblWelcome;
private JLabel lblMain;
private JPanel[] pnlAccDetails;
}
I have tried using both a CardLayout and the "revalidate();" "repaint();" and "pack();" options and I'm stumped as to why it's not showing. Thanks in advance for any help that can be offered.
EDIT:
While cutting down my code, if the "resizing" method is removed, the objects are shown when the panels change. I would like to avoid having to remove this completely as it's a smooth transition for changing the JFrame size.
#John smith it is basic example of switch from one panel to other panel I hope this will help you to sort out your problem
Code:
package stack;
import java.awt.BorderLayout;
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.JLabel;
import javax.swing.JPanel;
public class RemoveAndAddPanel implements ActionListener{
JFrame frame;
JPanel firstPanel;
JPanel secondPanel;
JPanel controlPanel;
JButton nextButton;
public RemoveAndAddPanel() {
JFrame.setDefaultLookAndFeelDecorated(true);
frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
firstPanel = new JPanel();
firstPanel.add(new JLabel("FirstPanel"));
firstPanel.setPreferredSize(new Dimension(100,100));
secondPanel = new JPanel();
secondPanel.add(new JLabel("Second panel"));
secondPanel.setPreferredSize(new Dimension(100,100));
nextButton = new JButton("Next panel");
controlPanel = new JPanel();
nextButton.addActionListener(this);
controlPanel.add(nextButton);
frame.setLayout(new BorderLayout());
frame.add(firstPanel,BorderLayout.CENTER);
frame.add(controlPanel, BorderLayout.SOUTH);
frame.setVisible(true);
frame.setSize(300,100);
}
#Override
public void actionPerformed(ActionEvent e) {
if(e.getSource() == nextButton) {
frame.remove(firstPanel);
frame.add(secondPanel);
nextButton.setEnabled(false);
}
frame.validate();
}
public static void main(String args[]) {
new RemoveAndAddPanel();
}
}
As mentioned in the edit, the problem lay within the resizing method. When the timer stopped, it wouldn't go anywhere, causing the UI to not load. The fix to the code is clearing the screen and adding the call to resizing to the actionlistener. Then adding a call to the next method after:
timer.stop();
Thanks for getting me to remove the mess around it and find the source of the problem #matt & #Hovercraft Full of Eels upvotes for both of you.
The main thing to consider while changing panel in a jframe is the layout, for a body(main) panel to change to any other panel the parent panel must be of type CardLayout body.setLayout(new java.awt.CardLayout());
After that you can now easily switch between panels wiht the sample code below
private void updateViewLayout(final HomeUI UI, final JPanel paneeelee){
final JPanel body = UI.getBody(); //this is the JFrame body panel and must be of type cardLayout
System.out.println("Page Loader Changing View");
new SwingWorker<Object, Object>() {
#Override
protected Object doInBackground() throws Exception {
body.removeAll();//remove all visible panel before
body.add(paneeelee);
body.revalidate();
body.repaint();
return null;
}
#Override
protected void done() {
UI.getLoader().setVisible(false);
}
}.execute();
}

Trying To Delay the Appearance of JLabels in a JDialog

Hi I've there a little problem: What I want is to delay the appearance of JLabels in a JDialog-Window, in terms of that the first line of JLabels shoud come out and then two seconds later the second line of Jlabels etc.
I've tried something with Windowlistener,the doClick()-Method etc., bu every time the Jdialog revalidates all of its panels AT ONCE and shows them without any delaying!
Please help me(Just copy the code below and try out)!
package footballQuestioner;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.border.EtchedBorder;
import javax.swing.border.TitledBorder;
public class attempter {
public static void main(String[] args) throws InterruptedException {
JDialog dialog = new Punkte();
}
}
class Punkte extends JDialog {
private JPanel screenPanel = new JPanel(new GridLayout(4, 1));
private JButton button = new JButton();
private int i = 1;
private class WindowHandler implements WindowListener {
#Override
public void windowActivated(WindowEvent e) {
}
#Override
public void windowClosed(WindowEvent e) {
}
#Override
public void windowClosing(WindowEvent e) {
}
#Override
public void windowDeactivated(WindowEvent e) {
}
#Override
public void windowDeiconified(WindowEvent e) {
}
#Override
public void windowIconified(WindowEvent e) {
}
#Override
public void windowOpened(WindowEvent e) {
button.doClick(1000);
button.doClick(1000);
button.doClick(1000);
button.doClick(); // here im trying to delay the appearance of the
// JLabels....
}
}
private class ButtonHandler implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
switch (i) {
case 1:
settingUpPanel(getPanelFromScreenPanel(i), "Right", new Color(
102, 205, 0));
settingUpPanel(getPanelFromScreenPanel(i), "Wrong", Color.RED);
break;
case 2:
settingUpPanel(getPanelFromScreenPanel(i), "Trefferquote",
Color.YELLOW);
break;
case 3:
settingUpPanel(getPanelFromScreenPanel(i), "Ausgezeichnet",
Color.BLUE);
break;
}
System.out.println(i);
i++;
}
}
public Punkte() {
button.addActionListener(new ButtonHandler());
addWindowListener(new WindowHandler());
setModal(true);
setResizable(true);
setLayout(new BorderLayout());
setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
settingUpScreenPanel();
add(screenPanel);
setSize(1200, 1000);
centeringWindow();
setVisible(true);
}
private void settingUpScreenPanel() {
JPanel titlePanel = new JPanel(new GridBagLayout());
JPanel rightWrongCountPanel = new JPanel(new GridLayout(1, 2));
JPanel shareOfRightQuestions = new JPanel(new GridBagLayout());
JPanel grade = new JPanel(new GridBagLayout());
settingUpPanel(titlePanel, "Result", Color.BLACK);
// settingUpPanel(rightWrongCountPanel,
// "Right: "+numberOfRightAnsers+"/6",new Color(102,205,0));
// settingUpPanel(rightWrongCountPanel,
// "Wrong: "+(6-numberOfRightAnsers)+"/6", Color.RED);
// settingUpPanel(shareOfRightQuestions,
// "Trefferquote: "+(numberOfRightAnsers*100/6)+"%",Color.YELLOW);
// settingUpPanel(summaSummarum,
// getBufferedImage("footballQuestioner/Strich.png"));
// settingUpPanel(grade,"Aushezeichnet", Color.BLUE);
borderingJPanel(screenPanel, null, null);
titlePanel.setOpaque(false);
rightWrongCountPanel.setOpaque(false);
shareOfRightQuestions.setOpaque(false);
grade.setOpaque(false);
screenPanel.add(titlePanel);
screenPanel.add(rightWrongCountPanel);
screenPanel.add(shareOfRightQuestions);
screenPanel.add(grade);
}
private void settingUpPanel(JComponent panel, String string, Color color) {
Font font = new Font("Rockwell Extra Bold", Font.PLAIN, 65);
JPanel innerPanel = new JPanel(new GridBagLayout());
JLabel label = new JLabel(string);
label.setForeground(color);
label.setFont(font);
innerPanel.add(label);
innerPanel.setOpaque(false);
panel.add(innerPanel);
panel.validate();
panel.repaint();
}
public JPanel getPanelFromScreenPanel(int numberOfPanel) {
JPanel screenPanel = (JPanel) getContentPane().getComponent(0);
JPanel labelPanel = (JPanel) screenPanel.getComponent(numberOfPanel);
return labelPanel;
}
public void centeringWindow() {
Dimension dimension = Toolkit.getDefaultToolkit().getScreenSize();
int x;
int y;
x = (int) (dimension.getWidth() - getWidth()) / 2;
y = (int) (dimension.getHeight() - getHeight()) / 2;
setLocation(x, y);
}
public void borderingJPanel(JComponent panel, String jPanelname,
String fontStyle) {
Font font = new Font(fontStyle, Font.BOLD + Font.ITALIC, 12);
if (jPanelname != null) {
panel.setBorder(BorderFactory.createTitledBorder(BorderFactory
.createEtchedBorder(EtchedBorder.LOWERED, Color.GRAY,
Color.WHITE), jPanelname,
TitledBorder.DEFAULT_JUSTIFICATION,
TitledBorder.DEFAULT_POSITION, font));
} else if (jPanelname == null || fontStyle == null) {
panel.setBorder(BorderFactory.createTitledBorder(BorderFactory
.createEtchedBorder(EtchedBorder.LOWERED, Color.BLACK,
Color.WHITE)));
}
panel.setOpaque(false);
}
}
This is a really good use case for javax.swing.Timer...
This will allow you to schedule a callback, at a regular interval with which you can perform an action, safely on the UI.
private class WindowHandler extends WindowAdapter {
#Override
public void windowOpened(WindowEvent e) {
System.out.println("...");
Timer timer = new Timer(2000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
JPanel panel = getPanelFromScreenPanel(1);
panel.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
for (int index = 0; index < 100; index++) {
panel.add(new JLabel(Integer.toString(index)), gbc);
}
panel.revalidate();
}
});
timer.start();
timer.setRepeats(false);
}
}
Now, if you wanted to do a series of actions, separated by the interval, you could use a counter to determine the number of "ticks" that have occurred and take appropriate action...
private class WindowHandler extends WindowAdapter {
#Override
public void windowOpened(WindowEvent e) {
System.out.println("...");
Timer timer = new Timer(2000, new ActionListener() {
private int counter = 0;
private int maxActions = 10;
#Override
public void actionPerformed(ActionEvent e) {
switch (counter) {
case 0:
// Action for case 0...
break;
case 1:
// Action for case 1...
break;
.
.
.
}
counter++;
if (counter >= maxActions) {
((Timer)e.getSource()).stop();
}
}
});
timer.start();
}
}
Take a look at How to use Swing Timers for more details

Increment/decrement with GUI(Java)

I am supposed to implement an application to the user that has 2 buttons(Increment/decrement) and a label. When increment is pressed the number increases and decreases by one when decrement is pressed. The number starts at 50. I have it to where it shows the buttons and they work, but they work on 2 different variables, so their is 2 number printed to the screen instead of 1. My question is how can i make the button act on only one number. I have seen people use push etc. but is there another way to do this by passing in a value to both or something? Thanks
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class ButtonModifier
{
public static void main(String[] args)
{
JFrame frame = new JFrame();
FlowLayout flow = new FlowLayout();
frame.getContentPane().setLayout(flow);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400,300);
frame.setTitle("Button Modifier");
IncrementPanel panel = new IncrementPanel();
DecrementPanel panel1 = new DecrementPanel();
frame.add(panel);
frame.add(panel1);
frame.setVisible(true);
}
}
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class DecrementPanel extends JPanel
{
private JButton button1;
private JLabel label;
private int number = 50;
public DecrementPanel()
{
button1 = new JButton("Decrement");
button1.addActionListener(new /*DecrementPanel.*/ButtonListener());
label = new JLabel("" + number);
this.add(button1);
this.add(label);
}
private class ButtonListener implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
//int increment = 50;
number--;
label.setText("" + number);
}
}
}
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class IncrementPanel extends JPanel
{
private JButton button;
private JLabel label;
int number = 50;
public IncrementPanel()
{
button = new JButton("Increment");
button.addActionListener(new ButtonListener());
label = new JLabel("" + number);
this.add(button);
this.add(label);
}
private class ButtonListener implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
//int increment = 50;
number++;
label.setText("" + number);
}
}
}
I am supposed to implement an application to the user that has 2 buttons(Increment/decrement) and a label."
Then why do you have two?
IncrementPanel panel = new IncrementPanel();
DecrementPanel panel1 = new DecrementPanel();
Just use one and change the text on that one
Should be more like this
public class ButtonModifier extends JFrame {
private JLabel numberLabel = new JLable("50");
private JButton decrease = new JButton("-1");
private JButton increase = new JButton("+1");
private static int num = 50;
public ButtonModifier(){
setLayout(new GridLayout(1, 3));
add(increase);
add(numberLabel);
add(decrease);
increase.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
num++;
numLabel.setText("" + num);
}
});
decrease.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
num--;
numLabel.setText("" + num);
}
});
}
public static void main(String[] args){
JFrame frame = ButtonModifier();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400,300);
frame.setTitle("Button Modifier");
frame.setVisible(true);
}
}
You should have one JLabel which will display the only number in your program.
Then your two buttons will do operations on that number and update the label.
Your mistake is that each Panel has its own number and its own Label to display the number.
public class ButtonModifier {
private static int number = 50;
private static JLabel label;
public static void main(String[] args) {
JFrame frame = new JFrame();
label = new JLabel("" + number);
// <SNIP>
JButton increment = new JButton("Increment");
increment.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent event) {
number++;
label.setText("" + number);
}
}
JButton decrement = new JButton("Increment");
increment.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent event) {
number--;
label.setText("" + number);
}
}
frame.add(label);
frame.add(increment);
frame.add(decrement);
frame.setVisible(true);
}
}
An important note: Swing is not thread-safe, and all the operations with GUI components must be performed on Event Dispatch Thread. So your main must actually look this way:
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
// Here you create the frame and all the components
}
});
}
Take a look at this program :
import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.Font;
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;
public class IncDecApp extends JFrame {
private JButton incBtn = new JButton("Increment");
private JButton decBtn = new JButton("Decrement");
private JPanel lowPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
private JLabel showLbl = new JLabel("00", JLabel.CENTER);
private Font myFont = new Font("Tahoma", Font.BOLD, 60);
private int valueInt;
public IncDecApp() {
setTitle("IncDec Application =)");
setDefaultCloseOperation(EXIT_ON_CLOSE);
lowPanel.add(incBtn);
lowPanel.add(decBtn);
incBtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
valueInt = Integer.parseInt(showLbl.getText());
valueInt++;
if (valueInt >= 10) {
showLbl.setText(String.valueOf(valueInt));
} else {
showLbl.setText("0" + String.valueOf(valueInt));
}
}
});
decBtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
valueInt = Integer.parseInt(showLbl.getText());
if (valueInt > 0) {
valueInt--;
}
if (valueInt >= 10) {
showLbl.setText(String.valueOf(valueInt));
} else {
showLbl.setText("0" + String.valueOf(valueInt));
}
}
});
showLbl.setFont(myFont);
add(showLbl, BorderLayout.CENTER);
add(lowPanel, BorderLayout.SOUTH);
pack();
setLocationRelativeTo(null);
setVisible(true);
}
public static void main(String[] args) {
new IncDecApp();
}
}
Create the JLabel in the main function. Have the incrementPanel and DecrementPanel classes constructors take a JLabel as an argument that they store as a private variable. The ButtonListeners csn also be passed the JLabel as an argument. Now the button listeners csn update a common JLabel.
Now, you can improve things by combining the code of IncrementPanel and DecrementPanel classes by passing an int in the constructor indicating the increment of +1 or -1.
A quick and dirty way to implement the functionality is through the use of anonymous classes implementing button listeners within a single monolithic class.
import java.awt.*;
import java.awt.event.*;
import java.applet.*;
public class ButtonApplet extends Applet implements ActionListener{
Button buttonInc, buttonDec;
int x=0;
public void init(){
buttonInc=new Button("Increment");
buttonDec=new Button("Decrement");
buttonInc.addActionListener(this);
buttonDec.addActionListener(this);
add(buttonInc);
add(buttonDec);
}
public void paint(Graphics g){
g.drawString("Count is : "+x,50,100);
}
public void actionPerformed(ActionEvent ev){
if(ev.getSource() == buttonInc)
{
x++;
repaint();
}
else if(ev.getSource() == buttonDec){
x--;
repaint();
}
}
}
Make Java GUI Application using AWT
You are required to make one label (Count), one textfield, one button (Increment), one button (Decrement) and one button (Close)
When the increment button is clicked, you need to increment the value in textfield, value should be incremented again and again when the button is clicked
When the decrement button is clicked, you need to decrement the value in textfield, value should be decremented again and again when the button is clicked
When the close button is clicked, you need to close the AWT Frame

Categories

Resources