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Generate JFrames in a loop, naming issue

Beginner Java programmer here. I'm trying to create a card game to learn more about Java. I have an array of names I pulled out a database. For each String in the array I want to create a JPanel and inside JLabels where I will set the name, power, health, etc.
The problem is when I create these in a loop they all have the same name and overwrite each other. Since I read Java doesn't have dynamic Variable names, how do I solve this?
public void loadDatabaseCardElements(ArrayList cards) {
ArrayList<String> buildCards = cards;
int i;
for(i = 0; i != buildCards.size();) {
String var = buildCards.get(0);
//create the Panel etc
JPanel mainHolder = new JPanel();
mainHolder.setLayout(new BoxLayout(mainHolder, BoxLayout.PAGE_AXIS));
JLabel name = new JLabel("Name: " + var);
JLabel powerLabel = new JLabel("Power: ");
JLabel healthLabel = new JLabel("Health: ");
JLabel armorLabel = new JLabel("Armor: ");
JLabel type1Label = new JLabel("Type1");
JLabel type2Label = new JLabel("Type2: ");
JLabel ability1Label = new JLabel("Ability1: ");
JLabel ability2Label = new JLabel("Ability2: ");
JLabel ability3Label = new JLabel("Ability3: ");
JButton card1 = new JButton("Add to deck");
mainHolder.add(name);
mainHolder.add(powerLabel);
mainHolder.add(healthLabel);
mainHolder.add(armorLabel);
mainHolder.add(type1Label);
mainHolder.add(type2Label);
mainHolder.add(ability1Label);
mainHolder.add(ability2Label);
mainHolder.add(ability3Label);
mainHolder.add(card1);
mainHolder.setBorder(BorderFactory.createLineBorder(Color.black));
mainHolder.setPreferredSize( new Dimension( 130, 200 ) );
frame1.add(mainHolder, BorderLayout.WEST);
SwingUtilities.updateComponentTreeUI(frame1);
card1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
preDeck.add(var); //add to another array when clicked
}
});
if (buildCards.size() != 0) {
buildCards.remove(0);
} else {
}
}
}

The reason for overwriting all the panels with same name is due to this part of your code:
int i;
for(i = 0; i != buildCards.size();) {
String var = buildCards.get(0);
You are assigning the first element of your list to each JLabel. This could help you achieve what you need:
for(int i = 0; i < buildCards.size(); i++){
String var = buildCards.get(i);
// Followed by your code
}

set a growable layout for a standard jpanel in the frame and then add a new jpanel to the standard jpanel every time. this should solve the naming problem. if u need access to each panel, you can store them in an array

Trying to add item listener to a JCheckBox object

I am trying add an item listener to a checkbox to see if its been checked, and if it is, to be added to a list of SQL table names to be selected. Inversely, if it is not selected then remove it from the list. I cannot add a listener though to any checkbox because "they are not effitively final". What can I do/is there a better way to attack it?
My method:
public JPanel drawChecks(){
ArrayList<String> list = MainFrame.grabSQLTableNames();
int index = list.size();
int rows = 1;
while(index > 1){
rows++;
index = index - 3;
}
GridLayout c = new GridLayout(rows, 3);
JPanel panel = new JPanel(c);
JCheckBox check[] = new JCheckBox[list.size()];
for(int x = 0; x < list.size(); x++){
check[x] = new JCheckBox(list.get(x));
check[x].setVisible(true);
check[x].addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
if (check[x].getState == true){
//do something
}
}
});
panel.add(check[x]);
}

Get the source of the event using the getSource method of the ItemEvent
public void itemStateChanged(ItemEvent e) {
JCheckBox checkBox = (JCheckBox)e.getSource();
if ( checkBox.isSelected() ){
//do something
}
}
For future reference, please read the following for tips on posting code examples for asking questions on stack overflow: https://stackoverflow.com/help/mcve

java dynamic display JLabel

I have a button. If I click this button, a popup appears. The popup asking me to write a word. if I write a word 6 letter, 6 jlabels appear, but if I enter another word shorter, the JLabels do not disappear
I want my JLabels may decrease according to a shorter word, but i don't know :(
thx for your great help !
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
//BUTTON 1 WORD
Controller c = new Controller();
try {
final JFrame popup = new JFrame();
//display popup
word = JOptionPane.showInputDialog(popup, "Enter one word", null);
//control the length of the word
c.controleW(word);
//display jlabel lenght of word
keyNumber.setText(String.valueOf(word.length()));
//JLabels displays depending on the word length
int pixels = 50;
for (int i = 0; i < word.length(); i++) {
label = new JLabel("_");
label.setBounds(pixels, 200, 30, 30);
add(label);
label.repaint();
pixels += 20;
}
} catch (Exception e) {
System.out.println(e);
}
}
And my class to control the length of the word
public String controleW(String word) {
boolean flag = false;
final JFrame popup = new JFrame();
while (flag == false) {
if (word.length() <= 3) {
word = JOptionPane.showInputDialog(popup, "Enter one word", null);
} else {
flag = true;
}
};
return null;
}

You are always adding labels in your method, never removing any, thus running the code twice will indeed add labels twice. To fix it, you can simply add a removeAll(); in jButton1ActionPerformed before you add any labels. This makes sure that any previously added components will be removed.

Adding multiple instances of a JButton to JFrame in grid

The code below is supposed to create and object instance for a specific type (say color) JButton I want to represent in a grid. When I iterate through the for-loop to add the buttons to the jframe it adds nothing. But if I add a single instance variable it will add that. Anybody have an idea?
public class Grid {
protected JButton [][] board;
private JButton player;
private JButton openCell;
private JButton wall;
private JButton closedCell;
public Grid(String [] args) { // args unused
// Instantiation
board = new JButton [6][6];
layout = new String [6][6];
blueCell = new JButton("BLUE CELL");
redCell = new JButton("RED CELL");
greenCell = new JButton("GREEN CELL");
whiteCell = new JButton("WHITE CELL");
// Configuration (add actions later)
// Decoration
blueCell.setBackground(Color.blue);
redCell.setBackground(Color.red);
greenCell.setBackground(Color.green);
whiteCell.setBackground(Color.white);
for (int rows = 0; rows < 6; rows++) {
for (int cols = 0; cols < 6; cols++) {
if ((layout[rows][cols]).equals('*')) {
board[rows][cols] = blueCell;
}
else if ((layout[rows][cols]).equals('.')) {
board[rows][cols] = redCell;
}
else if ((layout[rows][cols]).equals('x')) {
board[rows][cols] = greenCell;
}
else {
board[rows][cols] = whiteCell;
}
}
}
JFrame game = new JFrame();
game.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
game.setLayout(new GridLayout (6, 6));
game.setSize(500, 500);
for (int i = 0; i < board.length; i++) {
for (int j = 0; j < board.length; j++) {
if ((board[i][j]).equals(blueCell)) {
grid.add(blueCell);
}
else if ((board[i][j]).equals(redCell)) {
grid.add(redCell);
}
else if ((board[i][j]).equals(greenCell)) {
grid.add(greenCell);
}
else {
grid.add(whiteCell);
}
}
}
grid.setVisible(true);
} // end of constructor
} // end of Grid class

You can add a component to your GUI only once. If you add it to another component, it will be removed from the previous component. You're trying to add the same JButtons several times, and that won't work. Instead you're going to have to create more JButtons. Consider having your buttons share Actions which is allowed.
If you need more help, consider posting compilable code (your current code is not), a small runnable, compilable program that demonstrates your problem, in other words, an sscce.
Edit
You comment:
But don't these count as instances of a JButton not the same JButton? (I don't understand what your answer meant...)
Think of it mathematically... how many JButtons do you create in your code above? Well, this is easy to figure, exactly 4:
blueCell = new JButton("BLUE CELL");
redCell = new JButton("RED CELL");
greenCell = new JButton("GREEN CELL");
whiteCell = new JButton("WHITE CELL");
So, now ask yourself, how many JButtons are you trying to display in your GUI with these four JButtons? If it's four, then you're possibly OK (as long as you use each button), but if it's more, then you're in trouble. From your 6x6 grid, board = new JButton [6][6];, it looks like you're trying to display 36 JButtons, and if this is true, you've got problems.
But again, if still stuck, please consider creating and posting an sscce.

Creating dynamic JLabels and JButtons

I am trying to create dynamic JButton and JLabel based on the number of URLs defined in the properties file.
What I have tried so far is:
AppResources.properties file
urls=http://google.com,http://stackoverflow.com,http://gmail.com
urlLabels=Internet Users,MPLS Users,Physical Access (Not Advised)
In my Java program I am reading the properties file and based on the comma separator splitting the string and now i need to generate the buttons and labels accordingly. Like the first URL Label --> first URL as Button and so on.
The way I have done this so far is:
String url = properties.getProperty("urls");
String urlLabel = properties.getProperty("urlLabels");
String[] jButton = url.split(",");
String[] jLabel = urlLabel.split(",");
for (int i = 0; i < jLabel.length; i++) {
JLabel labels = new JLabel(jLabel[i]);
panel.add(labels);
for (int j = 0; j < jButton.length; j++) {
JButton button = new JButton(jButton[j]);
panel.add(button);
}
}
But it prints the button three times for a label. How to fix this? Also how to write the action listeners for these buttons?

If you want to implement action listeners for your buttons, you can simply create and add a new ActionListener while creating the button.
Example :
for (int i = 0; i < jLabel.length; i++) {
final String str = jLabel[i];
JLabel labels = new JLabel(str);
panel.add(labels);
JButton button = new JButton(jButton[i]);
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(panel, str);
}
});
panel.add(button);
}

Remove the inner loop (j based).