CODEWITHSUNDEEP
javaswingjlabel
Sajad
Sajad

Reputation: 2363

JLabels don't show when button clicked

I want to see labels when my show Button clicked, But don't work!

public class d4 extends JFrame implements ActionListener {

Connection con;
String dbName = "mydb";
String bdUser = "root";
String dbPassword = "2323";
String dbUrl = "jdbc:mysql://localhost/mydb";
JButton showButton;
static JLabel[] lbl;
JPanel panel;

public d4() {

try {
    con = DriverManager.getConnection(dbUrl, bdUser, dbPassword);
    System.out.println("Connected to database successfully!");

} catch (SQLException ex) {
    System.out.println("Could not connect to database");
}

add(mypanel(), BorderLayout.PAGE_START);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(400, 500);
setLocation(300, 30);
setVisible(true);
pack();
}

public JPanel mypanel() {
panel = new JPanel(new FlowLayout(FlowLayout.LEFT));
showButton = new JButton("Show");
showButton.addActionListener(this);
panel.add(showButton);
revalidate();
repaint();

return panel;
}

@Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == showButton) {
            lbl = recordsLabel();
        for(JLabel jlabel : lbl){
            panel.add(jlabel);  
}
}
public JLabel[] recordsLabel() {
try {
    Statement st1 = con.createStatement();
    ResultSet result1 = st1.executeQuery("select * from mytable");
    ArrayList<String> lableList = new ArrayList<>();
    while (result1.next()) {
        String resultRow = result1.getString(1) + " " + result1.getString(2);
        System.out.println(resultRow);
        lableList.add(resultRow);
    }
    Object[] arrayResultRow = lableList.toArray();

    int rows = result1.last() ? result1.getRow() : 0;

    lbl = new JLabel[rows];
    for (int i = 0; i < rows; i++) {
        lbl[i] = new JLabel(arrayResultRow[i].toString());
    }

} catch (SQLException sqle) {
    System.out.println("Can not excute sql statement");
}
return lbl;
}

public static void main(String[] args) {
new d4();
}
}

Upvotes: 0

Views: 147

Answers (3)

Richard
Richard

Reputation: 509

You have not implemented the ActionListener interface

EDIT: your updated code shows that you have. Now as Hovercraft Full Of Eels suggests, the next step is to isolate the problem with debugging techniques.

Upvotes: 5

Hovercraft Full Of Eels
Hovercraft Full Of Eels

Reputation: 285405

You're calling myPanel() twice, and by doing this, you're adding JLabels to a JPanel that is never added to the GUI.

Solution: don't do this. Your myPanel() is kind of screwy to begin with since it returns a JPanel and also sets the class field panel at the same time. So set the panel variable once, and then use the variable.

And yes, revalidate() and repaint() the container after adding components to it as per Azad's recommendations (1+ to him).

Upvotes: 4

Azad
Azad

Reputation: 5055

Try calling revalidate() and repaint() after adding the lables to the panel, you need also to call pack() on the frame for resizing the frame to fit the new components.

Upvotes: 4

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