I want a button to change the contentPane in a frame. An admin panel and a user panel in two different JPanel classes that gets called in a MainWindow class with a frame.
My code looks as follows:
The method the button calls:
public void ChangeContent() throws Exception{
MainWindow mw = new MainWindow();
AdminUI admin = new AdminUI ();
mw.frame.getContentPane().removeAll();
mw.frame.setContentPane(admin);
mw.frame.revalidate();
mw.frame.repaint();
}
This is the method being called in my "public MainWindow()" method in the MainWindow class (the one with the frame) to show the contentPane in the beginning:
public void Admin() throws Exception {
frame = new JFrame("Admin Panel");
frame.setResizable(false);
frame.setBounds(100, 100, 256, 457);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
AdminUI Admin = new AdminUI();
frame.setContentPane(Admin);
}
An equal method exists for the userUI.
I have tried just called the userUI() method in the MainWindow when I press a button, but that doesn't refresh the window, and neither does the ChangeConten() method. I need some help. I used the search feature on Stackoverflow to no success.
Related
Hi i need help with this code.
I really need help...
package Window;
import java.awt.Color;
import javax.swing.*;
public class Window
{
public static void build()
{
//Create Elements
JFrame frame = new JFrame();
JButton send = new JButton();
JTextArea dialog = new JTextArea();
JTextArea input = new JTextArea();
JScrollPane scroll=new JScrollPane(
dialog,
JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER
);
send.setLocation(505,520);
send.setSize(80,20);
send.setBackground(Color.green);
send.setText("Send");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(590, 600);
frame.setTitle("Bot");
frame.setLayout(null);
frame.setResizable(false);
frame.setBackground(Color.green);
dialog.setLocation(5, 5);
dialog.setSize(575,510);
input.setLocation(15, 520);
input.setSize(490,25);
frame.add(send);
frame.add(dialog);
frame.add(input);
frame.add(scroll);
}
void show()
{
frame.setVisible(true);
}
}
I want to be able to set the frame visible from a separate method. But it cant find the frame object.
Is there any way to fix this??
You need to let the show() method know what to set visible.
Right now, you're defining the JFrame variable only for the scope of your build() method (so it cannot be accessed from other methods directly).
If this is your GUI class, you can make the JFrame a class variable. Like this:
public class Window {
JFrame frame = new JFrame();
.
.
Or you can just define it and create the actual JFrame in your build() method:
public class Window {
JFrame frame;
public static void build(){
frame = new JFrame();
.
.
Now you will be able to access the frame variable in your show() method. If you want to access it in a different class' method for example, you can just pass the frame object as an argument. Like so: objectOfDifferentClass.myMethod(frame); with the method in this class being defined as myMethod(JFrame frame){...}
You can read more about variable scopes here.
public class Create_JFrame extends JFrame{
public Create_JFrame(){
//Create a Frame
JFrame Frame = new JFrame("Bla-Bla");
JPanel Panel_1 = new JPanel();
JPanel Panel_2 = new JPanel();
JButton Option_1 = new JButton("Option-1");
//Layout management for Panels
Frame.getContentPane().add(BorderLayout.WEST, Panel_1);
//Add button to Panel
Panel_1.add(Option_1);
//Registering Listeners for all my buttons
Option_1.addActionListener(new ListenerForRadioButton(Panel_2));
//Make the frame visible
Frame.setSize(500, 300);
Frame.setVisible(true);
}//end of Main
}//end of Class
public class ListenerForRadioButton implements ActionListener{
JPanel Panel_2;
JButton browse = new JButton("Browse");
//Constructor, will be used to get parameters from Parent methods
public ListenerForRadioButton(JPanel Panel){
Panel_2 = Panel;
}
//Overridden function, will be used for calling my 'core code' when user clicks on button.
public void actionPerformed(ActionEvent event){
Panel_2.add(browse);
System.out.println("My listener is called");
}//end of method
}//end of class
Problem Statement:
I have 2 JPanel components in a a given JFrame. Panel_1 is having a Option_1 JButton. When user clicks on that I am expecting my code to add a JButton 'browse' in Panel_2 at runtime.
Runtime Output:
System is not adding any JButton in Panel_2. However, I see my debug message in output, indicating that system was successful in identifying user's click action on 'option-1'.
Question:
Why is JPanel not adding any component at Runtime?
Panel_2.add(browse);
Panel_2.revalidate();
adding a 'revalidate' will solve the problem.
There are some reasons. but:
usually it's because of using unsuitable LayoutManager.
sometimes it's because of adding the JPanel to it's root component in worng way. which any operation (add, remove,...) works but is not visible.
you must refresh the view when you make some changes on it, like adding or removing components to/from it.
try to use Panel_2.revalidate() to refresh.
if it doesn't work properly use it with Panel_2.repaint() method.
see Java Swing revalidate() vs repaint()
see Difference between validate(), revalidate() and invalidate() in Swing GUI
using setSize twice for your jframe is another way.
Frame.setSize(498, 300); then Frame.setSize(500, 300);
I am trying to open a GUI from my main GUI by pressing a button. When the button is pressed, this is executed:
WorkloadFactor wf = new WorkloadFactor();
wf.setVisible(true);
This doesn't open the WorkloadFactor GUI. I am confused by this because I have other GUIs that open this way without issue.
WorkloadFactor class works fine when I run it by itself but won't open when it is called by my main GUI. Below is my class without imports and stuff:
public class WorkloadFactor extends JPanel {
public WorkloadFactor() {
setLayout(new BorderLayout());
JTabbedPane tabbedPane = new JTabbedPane();
String[] tabnames = { "Zero", "One", "Two", "Three", "Four" };
for (int i = 0; i < tabnames.length; i++) {
tabbedPane.addTab(tabnames[i], createPane(tabnames[i]));
}
tabbedPane.setSelectedIndex(0);
JButton submit = new JButton("Submit All");
submit.setForeground(Color.RED);
add(tabbedPane, BorderLayout.CENTER);
add(submit, BorderLayout.SOUTH);
}
public JPanel createPane(final String t) {
JPanel contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
//setContentPane(contentPane); I think this might be it?
contentPane.setLayout(null);
setBounds(100, 100, 531, 347);
//***** all the components I am including then add them like so
//******contentPane.add(checkbox1);
//****** contentpane.add(label1);
return contentPane;
}
public static void main(String[] args) {
JFrame frame = new JFrame("Set Workload Factor Information");
frame.getContentPane().add(new WorkloadFactor());
frame.setBounds(100, 100, 531, 347);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
}
}
I have tried arranging things in so many ways, putting everything in the constructor and other changes but can't seem to find a reason why instantiating this WorkloadFactor class elsewhere and setting it visible won't work.
Does it have something to do with setContentPane(contentPane) vs contentPane.add(xxxx) and returning it?
Thank you for reading!
WorkloadFactor wf = new WorkloadFactor();
wf.setVisible(true);
To be blunt, this won't display anything. Please understand that WorkloadFactor extends JPanel and like all non-top level components must be placed into a container that is ultimately held by a top-level window in order to be displayed. Look at how you display it in your main method -- you first put it into a JFrame, and then display that JFrame. You must do the same thing if you want to display it on button press -- you need to put it into a JPanel or other container that is held by a JFrame or JDialog, or JOptionPane.
Make sure that you have properly registered the button on your main GUI which opens WorkLoadFactor GUI to an action listener.
Since you have not included code from your main GUI I can't confirm this is the issue. However it is a commonly overlooked issue.
Heres some suggestions from the Java documentation tutorials:
"Problem: I'm trying to handle certain events from a component, but the component isn't generating the events it should.
First, make sure you registered the right kind of listener to detect the events. See whether another kind of listener might detect the kind of events you need.
Make sure you registered the listener on the right object.
Did you implement the event handler correctly? For example, if you extended an adapter class, then make sure you used the right method signature. Make sure each event-handling method is public void, that the name spelled right and that the argument is of the right type."
source: Solving Common Event-Handling Problems
Make a JFrame and add a JButton in it than add action listener in button and add this code in it like this:
This code makes a frame with a button and when button is pressed new window is opened.
public class Example extends JFrame {
public Example() {
super("Title");
setLayout(new FlowLayout());
JButton b = new JButton("Open new Frame");
b.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
newWindow nw = new newWindow();
}
});
add(b);
}
}
newWindow Code:
public class newWindow extends JFrame {
newWindow() {
super("title");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(400,400);
setVisible(true);
}
}
I have a button that when pressed calls a changecolor() method in a different class where some drawing is done. The button listener works fine and I see from some logging that the color was in fact changed but my drawing is not updated. This is my current implementation:
(This method is called when a button is clicked)
public void changeWarningLightColor(){
System.out.println("change color method called");
if(warningLights.equals(Color.GREEN)){
warningLights=Color.RED;
System.out.println(warningLights);
repaint();
}
else{
warningLights=Color.GREEN;
repaint();
}
}
and my drawing is created in the same file in the above method as follows:
#Override
protected void paintComponent(Graphics g){
super.paintComponent(g);
g.drawSomething();
//draw a bunch of lines
}
My question is what is the proper way to call repaint() in order to actually update the drawing? Do I need to somehow call g.repaint() or do something different?
Separate class where the frame is created:
public class MainWindow extends JFrame {
public MainWindow(){
JPanel Window = new JPanel();
JPanel LeftSidePanel = new JPanel();
LeftSidePanel.setLayout(new BorderLayout());
LeftSidePanel.add(new DrawStatus(),BorderLayout.CENTER); //where the drawing is added
Window.setLayout(new BoxLayout(Window,0));
Window.add(LeftSidePanel);
add(Window);
}
public static void main(String[] args) {
//main method for showing the frame we created with the panels, and circles inside it
MainWindow frame = new MainWindow();
frame.setSize((int) (.75*Toolkit.getDefaultToolkit().getScreenSize().getWidth()),(int) (.75*Toolkit.getDefaultToolkit().getScreenSize().getHeight()));
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
frame.setTitle("DVPWS v1.0");
frame.setResizable(false);
MenuBar menu = new MenuBar();
frame.setJMenuBar(menu);
frame.setVisible(true);
}
}
If you are using a Jframe (most likely are) do
yourFrame.repaint();
Optionally
yourPanel.repaint();
In this case you could do
public MainWindow mw = new MainWindow();
mw.repaint();
If that doesnt work(i had a similar problem) than your going to have to make an instance of JFrame instead of extending it.
I'm following through a book called "The JFC Swing Tutorial (Second Edition)" and I'm pretty much at the start I have followed this code and it should be displaying the button and the label in the content pane, but All im getting is a blank screen. any ideas?
Thanks.
import java.awt.GridLayout;
import javax.swing.*;
public class m extends JFrame
{
void UserFrame()
{
//JFrame.setDefaultLookAndFeelDecorated(true);
JFrame frame = new JFrame("Hellow You");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel jp = new JPanel(new GridLayout(0,1));
//makes label
JLabel label = new JLabel("Sup ");
//adds to the frames content pane a label
frame.getContentPane().add(label);
JButton button = new JButton("Hai");
frame.getContentPane().add(button);
jp.add(button);
jp.add(label);
jp.setBorder(BorderFactory.createEmptyBorder(30,30,10,30));
//pack set the window to what it needs AKA to display all components
frame.pack();
//frame.setSize(250, 250);
//shows window
frame.setVisible(true);
}
public static void main(String[] args)
{
final m window = new m();
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
window.UserFrame();
}
});
}
}
Simply add
frame.add(jp);
just before
frame.pack();
What's happening here? You correctly add all your widgets to a JPane, but you basically threw that JPane away and didn't use it anywhere.
This will be sufficient just to get it to work properly.
If you want to do it correctly, you should also remove frame.getContentPane().add(label); and frame.getContentPane().add(button); (Thank you #dic19 for noting that!). These will not work the way you used it.