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Why does my button disappear from my borderlayout when I add an actionListener to it?

I am writing the back end code for my java project which is implementing a fitness logger. For some reason when I put the actionListener function to a button in my Border Layout then the button disappears.
I tried setting the function in different places in the constructor.
public class Buttons extends JFrame implements ActionListener {
JFrame frame = new JFrame("Menu");
JPanel MyPanel= new JPanel();
JButton b1= new JButton("Daily Logger");
JButton b2= new JButton("View Weekly Logs");
JButton b3= new JButton("Weight Calculator");
JButton b4= new JButton("BMI Calculator");
JButton b5= new JButton("Log Out");
public Buttons(){
MyPanel.setLayout(new BorderLayout());
MyPanel.add(b1, "North");
MyPanel.add(b2, "Center");
MyPanel.add(b3, "East");
MyPanel.add(b4, "West");
MyPanel.add(b5, "South");
b1.addActionListener(this);
add(b1);
frame.getContentPane().add(MyPanel, "North");
frame.setSize(500,115);
frame.setVisible(true);
}
public static void main(String[] args) {
new Buttons();
}
#Override
public void actionPerformed(ActionEvent e) {
String command = e.getActionCommand();
if(command.equals("Daily Logger"))
myMethod();
}
public void myMethod() {
JOptionPane.showMessageDialog(this,"Onto the next step");
}
}
I expected the button to show up in the border layout when I add the actionListener function but it disappears. If the button did work as it should it should implement the myMethod() function. My main goal is to show my JTable that I created in another class to show up when the button is pressed.

add(b1);
Should be removed. The code has already added it via:
MyPanel.add(b1, "North");
A BorderLayout accommodates up to five components, each in a separate layout constraint. If a component is added twice, in different areas, it faces two problems:
A component can only appear in one place.
The component 'overwrites' the original component added to that area of the layout.
More general tips:
Please learn common Java nomenclature (naming conventions - e.g. EachWordUpperCaseClass, firstWordLowerCaseMethod(), firstWordLowerCaseAttribute unless it is an UPPER_CASE_CONSTANT) and use it consistently.
For better help sooner, add a minimal reproducible example or Short, Self Contained, Correct Example. Note: The posted code only needed appropriate import statements to be an MRE / SSCCE.
MyPanel.add(b3, "East"); re East
There are constants for this. E.G. BorderLayout.EAST. always use the constants for compile time checking.
But BorderLayout.LINE_END is sensitive to the locale. It will appear on the RHS for left to right languages, and the left for right to left languages.
All Swing & AWT GUIs should be created & updated on the EDT (Event Dispatch Thread).
The code both extends and keeps a reference to, JFrame. Keep the latter, ditch the former.
Be sure to add the java (language) and swing (GUI toolkit) tags to questions! The only reason I saw this was because I (extraordinarily) checked the question listing for the jframe tag! To the best of my recollection, it's the first time I've ever checked that tag's question listing. Even more ironic, it did not make the list of 5 tags I saw as being most relevant to this question.
frame.getContentPane().add(.. can be shortened to frame.add(.. since Java 1.5.
frame.setSize(500,115); should better be frame.pack();, since 500 x 115 is no better than a guess, and will be 'wrong' for different OS' (the size of the content pane will change due to different frame decorations per system).

Java GUI Design: Use object or use method?

I have a noobie question about GUI designing in Java: should we use more methods or more objects? Take a very simple example: dialogs.
For a dialog, I can use a method or use an object:
Using Method:
public static void MakeDialog() {
final JFrame frame = new JFrame();
String help = "";//Reader.readhelp();
JTextArea contentArea = new JTextArea(help, 60, 60);
JScrollPane scroller = new JScrollPane(contentArea);
scroller.setPreferredSize(new Dimension (650,650));
JButton close = new JButton("Close");
close.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent a) {
frame.dispose();
}
});
JPanel panel = new JPanel();
panel.add(scroller);
panel.add(close);
frame.add(panel);
frame.setTitle("Help");
frame.setSize(700, 700);
frame.setVisible(true);
frame.setResizable(false);
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
}
Then I will just need to call this method need this dialog to show up.
However, I can have another approach: make a class of dialog:
public class MyDialog {
public MyDialog() {
final JFrame frame = new JFrame();
String help = "";//Reader.readhelp();
JTextArea contentArea = new JTextArea(help, 60, 60);
JScrollPane scroller = new JScrollPane(contentArea);
scroller.setPreferredSize(new Dimension (650,650));
JButton close = new JButton("Close");
close.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent a) {
frame.dispose();
}
});
JPanel panel = new JPanel();
panel.add(scroller);
panel.add(close);
frame.add(panel);
frame.setTitle("Help");
frame.setSize(700, 700);
frame.setVisible(true);
frame.setResizable(false);
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
}
}
The problem that really bothers me is: which one uses memory more efficiently? For one or two dialogs in a software, this is probably not a problem at all. If I need to deals with hundreds of dialog, I need to think about the memory resources that I might consume. According what I have learned so far, calling that method is better than creating MyDialog object, since memory will be released when once the method is processed. However, the object MyObject will be remained in memory if I don't take any action on it. The problem that I am facing is: after a few hours of developing, I found out that I only have a few MB of memory left and I have to quit Eclipse and restart my computer to release the memory.
Therefore:
1) Which one is better?
2) If creating object is better, how can I remove that object from memory if I am not going to use it anymore?

Memory usage is irrelevant here. The difference will be around 20 bytes, that will be garbage collected.
What matters is correct design. An object's constructor is not meant to have side effects like showing a dialog box. The goal of a constructor is to create an object with a specific state, by initializing its fields, in order to use the object later.
Your example doesn't do anything like that. You would be creating a MyDialog instance, and do nothing with it. All the constructor would do is to have a huge side-effect: displaying a dialog box.
Another bad point in this design is that you're using an instance field to store a value that is in fact a constant, not tied to any specifu MyDialog instance, and only relevant to the constructor. There is no reason at all to have such a field.
And finally, your method doesn't respect the Java naming conventions: methods start with a lower-case letter. And it should be named showDialog() instead of makeDialog, since it doesn't create a dialog box, but shows one.

I'm afraid this question is a bit too general to answer, since you're asking about any and all use cases of GUI design.
Let me instead refer to the specific scenario you mention, which is a dialog.
It might come as a surprise, what's considered as a Swing best practice when it comes to dialogs, is somewhere in between a method and a class.
When working with dialogs in Swing, on the one hand, it's considered a best practice to create a new class for the panel that contains all the GUI, and which will become the content pane of the dialog. On the other hand, you should create a method that will create (and possibly also display) the dialog. In that method, you'll do the following:
Create an instance of JDialog (usually, there's no need to subclass)
Create an instance of your custom panel class (e.g. MyDialogContentPaneClass)
Set the panel as the content pane of the dialog
Display and/or return the dialog

how to call active frame that already exist from another class that extends JDialog then remove all of its component?

I have class main extends jframe, it has a button that calls /shows another class that extends jdialog.
If the button from jdialog is triggered, it will dispose that dialog and will remove all component of jframe, then add it to a new jpanel.
What should I do?
Here's my new broken code:
public class mainz extends JFrame{
mainz(){
setVisible(true);
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
JToolBar r = new JToolBar();
r.add(Box.createHorizontalGlue());
add(r, BorderLayout.NORTH);
JButton n = new JButton();
r.add(n, BorderLayout.EAST);
n.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae){
show();
}
});
}
public void show(){
dialogz d = new dialogz(this);
d.setVisible(true);
}
public void lastHope(){
getContentPane().removeAll();
getContentPane().validate();
getContentPane().repaint();
}
public static void main (String[]args){
new mainz().setExtendedState(MAXIMIZED_BOTH);
}
}
public class dialogz extends JDialog{
public dialogz(final mainz owner) {
setSize(300, 300);
JButton n = new JButton("execute");
add(n);
final JFrame ew = (JFrame)super.getOwner();// <<
n.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae){
dispose();
//owner.lastHope;
ew.removeAll();// <<
ew.validate();// <<
ew.repaint();// <<
}
});
}
void yes(){
getOwner().removeAll();
getOwner().validate();
getOwner().repaint();
}
}
I know I can prevent my main class from extending jframe, and call it from main instead, but I want to do it like that...
Please help me ... T-T
Sorry for my English, I from a far away country ~,~"
update:
the error is
java.lang.ClassCastException: javax.swing.SwingUtilities$SharedOwnerFrame cannot be cast to javax.swing.JFrame
it will be done with delete the line that contain
// <<
then call lastHope();
but i think there's a another way to get that existing jframe to removeall
(by casting it first or something ~,~" )

You are calling getParent() but you never set the parent (or owner). That should happen in the constructor as already pointed out. Also, be mindful that getParent() returns a Container object and getOwner() returns a Window object. Both of these refer to the JFrame which is the parent and owner. If you want to use it as a JFrame, you'll have to cast the output as (JFrame). But removeAll() is in Container class so if that's all you want, there'll be no need for casting.
Update:
JFrame frame = new JFrame();
JDialog dialog = new JDialog(frame);//frame is owner
JFrame parentOfDialog = (JFrame)(dialog.getParent());
//OR
//JFrame parentOfDialog = (JFrame)(dialog.getOwner());
parentOfDialog.removeAll();
If you are using your custom class, pass JFrame in the constructor and call super.
Please read the javadoc on JDialog before you try to use it. Also, read more about inheritance.

I'm not clear on what your goal is, but if you want to change the components that are displayed in a container, such as a JFrame or JDialog's contentPane, then I recommend that you use a CardLayout to do this since it allows you to easily swap "views".
There could be two ways to do this:
Your JDialog class could use a reference to the JFrame that is passed in via its constructor (and you should then pass it immediately into the dialog's super constructor so that your modality will work correctly). You could then call any public methods in the JFrame's class.
Or since the JDialog is modal, the JFrame's code will halt while the dialog is visible. You could swap "views" immediately after the dialog has been disposed of and is no longer visible. this would keep the JFrame manipulating code in the JFrame class.
Edit: note that if you don't use CardLayout, then you're responsible for calling revalidate() and repaint() on any container who gets its components changed.
As an aside: since English is not your first tongue and nor is it the native language of many folks on this forum, please avoid using non-standard abbreviations. The clearer your communication with us, the easier it will be for us to understand you and help you.

I have a JLabel that doesn't want to update

I've looked at other JLabel threads and though similar, a few just don't seem to apply to what I'm experiencing. First, I want to say I am a novice when it comes to Java. Next, I am trying to follow tutorials and demos at the docs.oracle.com site. Now, I can update the label when I type something into a JTextField and there is an ActionListener on that...
But I also have a Menu, and when I select a Menu Item, that Action does not want to update the label.
Questions -
How do I have action listeners on both JTextFields and JMenuItems? Are there two ActionEvent methods or do I use one method and somehow identify each type of action?
If I use the same basic code in the JTextField ActionEvent and JMenuItem ActionEvent, the JLabel updates correctly with the JTextField event but not JMenuItem event. They both use the messageField.setText property. Could the JMenuItem action be doing something to block the setText?
I can easily copy code in here, but it's pretty spaghetti-like at the moment, so if you want to see anything, let me know specifically and I'll post it.
I would appreciate any assistance that anyone would be able to provide.
---edit---
Wow!! Thanks for all of the comments and suggestions.
1 - I know it has to be my code. As I mentioned, I am really just cobbling stuff together from demos and tutorials, and trying to learn Java along the way. I've just never gotten the hang of object oriented....
2 - I do know the individual Listeners are working. I'm using System.out.println to validate, as well as inspecting those labels in debug mode to see they have indeed changed.
3 - I will look at the various links and code posted here and see if I can figure out what's wrong with my code.
Really, thanks again!
---edit---
Here is what I originally had in my createAndShowGUI method....
private static void createAndShowGUI()
{
JFrame frame = new JFrame("Create XML for Photo Gallery");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
CreateGalleryXML window = new CreateGalleryXML();
frame.setJMenuBar(window.createMenuBar());
frame.add(new CreateGalleryXML());
frame.pack();
frame.setVisible(true);
}

Seems like you yourself are doing something wrong, in your code. Without a proper SSCCE it's hard to say what thing you doing wrong, since it works perfectly, using same ActionListener for both JMenuItem and JTextField.
Here is a sample program to match with yours :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class UpdateLabel
{
private JLabel label;
private String labelText;
private ActionListener action = new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
setLabelText((String) ae.getActionCommand());
label.setText(getLabelText());
}
};
private void setLabelText(String text)
{
labelText = text;
}
private String getLabelText()
{
return labelText;
}
private void createAndDisplayGUI()
{
final JFrame frame = new JFrame("Update Label");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setLocationByPlatform(true);
JMenuBar menuBar = new JMenuBar();
JMenu programMenu = new JMenu("Program");
JMenuItem exitMenuItem = new JMenuItem("Exit");
exitMenuItem.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
frame.dispose();
}
});
JMenu labelMenu = new JMenu("Label");
JMenuItem updateMenuItem = new JMenuItem("Update Label");
updateMenuItem.setActionCommand("Updated by JMenuItem");
updateMenuItem.addActionListener(action);
programMenu.add(exitMenuItem);
labelMenu.add(updateMenuItem);
menuBar.add(programMenu);
menuBar.add(labelMenu);
frame.setJMenuBar(menuBar);
JPanel contentPane = new JPanel();
label = new JLabel("I am the LABEL which will be updated!!");
contentPane.add(label);
JTextField tfield = new JTextField(10);
tfield.setActionCommand("Updated by JTextField");
tfield.addActionListener(action);
frame.add(contentPane, BorderLayout.CENTER);
frame.add(tfield, BorderLayout.PAGE_END);
frame.pack();
frame.setVisible(true);
}
public static void main(String... args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
new UpdateLabel().createAndDisplayGUI();
}
});
}
}
And here is the output in both the cases :
and
Do check out the main method, might be you had failed to put your code inside EDT - Event Dispatcher Thread, that can lead to such issues too. All updates on the Swing GUI, must be done on the Event Dispatcher Thread.
LATEST EDIT
It seems to me that CreateGalleryXML extends JPanel by the look of it. See at Line 3 of this below code taken from your update, here you are initializing a new Object of CreateGalleryXML inside, when you already had one Object window created at Line 1:
CreateGalleryXML window = new CreateGalleryXML();
frame.setJMenuBar(window.createMenuBar());
frame.add(new CreateGalleryXML());
So try to change the above thingy to this
CreateGalleryXML window = new CreateGalleryXML();
frame.setJMenuBar(window.createMenuBar());
frame.add(window);
and see what happens and Please do revert back again :-)

Use Action to encapsulate common functionality that must be shared by menus and related components. See this example that extends AbstractAction.

Pretty much everything you could need to know is in the Java tutorials. Down the bottom they have demo's on how to do both menu's and text fields. They include source code to look at as well.
There's not much more I can say that they don't say better, but in answer to your questions:
Both, you can have separate listener's on each component, or one that figures out what component is responsible for causing the action event. I would suggest you use separate ones for each thing.
Can't really say with out seeing the code, are you sure that the action on the JMenu is even firing? Does it print something to the console etc if you use System.out.println somewhere?

Java Refreshing a screen

I have a screen in which one of its components is made invisible depending on a boolean value. If the boolean changes after the screen has been created, how do I refresh the screen to take this into account?

I think revalidate() is more appropriate here if you are dealing with JComponents.
From the JavaDoc:
Supports deferred automatic layout.
Calls invalidate and then adds this component's validateRoot to a list of components that need to be validated. Validation will occur after all currently pending events have been dispatched. In other words after this method is called, the first validateRoot (if any) found when walking up the containment hierarchy of this component will be validated. By default, JRootPane, JScrollPane, and JTextField return true from isValidateRoot.
This method will automatically be called on this component when a property value changes such that size, location, or internal layout of this component has been affected. This automatic updating differs from the AWT because programs generally no longer need to invoke validate to get the contents of the GUI to update.

Call the validate() method on the container that needs to be laid out -- probably your window's content pane.

Try calling repaint() which in turn will call paintComponent().

I thought that (with Java 6?) you need not do anything... This should happen automatically - no?
With the following example, it does happen automatically...
public class TT extends JFrame
{
public TT()
{
setLayout(new FlowLayout());
JLabel label = new JLabel();
label.setText("Label:");
add(label);
final JTextField textField = new JTextField();
add(textField);
JButton button = new JButton();
button.setText("Button");
button.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
if (textField.isVisible())
{
textField.setVisible(false);
}
else
{
textField.setVisible(true);
}
}
});
add(button);
setSize(100,100);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
TT frame = new TT();
frame.setDefaultCloseOperation(TT.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}
}
[Add] And using a layout manager like GridBagLayout would also solve the problem of "Re-Laying out" the page.