I am very confused, many examples I have seen only deal with one button listener being passed. I want to be able to pass ALL Components of a View Class (JFrame) to the Controller Class which will have easy access to the listeners of those components. How Can I do this easily. This is what I've done so far with JMenuItem
, but in the JFrame i have more buttons, dont want to repeat in the Constructor every time.
public class EventController implements ActionListener {
private EventModel model;
private EventView view;
public EventController(){
model = new EventModel();
}
@Override
public void actionPerformed(ActionEvent e) {
if (e.getActionCommand().equals("add")) {
JOptionPane.showMessageDialog(null, "add button clicked");
} else if (e.getActionCommand().equals("edit")) {
JOptionPane.showMessageDialog(null, "edit button clicked");
} else if (e.getActionCommand().equals("delete")) {
JOptionPane.showMessageDialog(null, "delete button clicked");
}
}
//class View
public class EventView extends javax.swing.JFrame {
Connection conn = JavaConnect.ConnectDB();
PreparedStatement pst = null;
ResultSet rs = null;
public EventView() {
initComponents();
updateEventTable();
addEvent.addActionListener(new EventController());
addEvent.setActionCommand("add");
editEvent.addActionListener(new EventController());
editEvent.setActionCommand("edit");
deleteEvent.addActionListener(new EventController());
deleteEvent.setActionCommand("delete");
}
public void updateEventTable() {
try {
String sql = "SELECT date as 'Date',eventName as 'Name', time as 'Start Time' FROM Event";
pst = conn.prepareStatement(sql);
rs = pst.executeQuery();
tableEvent.setModel(DbUtils.resultSetToTableModel(rs));
tableEvent.getColumnModel().getColumn(0).setPreferredWidth(80);
tableEvent.getColumnModel().getColumn(1).setPreferredWidth(170);
tableEvent.getColumnModel().getColumn(2).setPreferredWidth(110);
}
catch (Exception e ) {
JOptionPane.showMessageDialog(null, e);
} finally {
try {
rs.close(); pst.close();conn.close();;
} catch(SQLException e){}
}
}
Create listener instance just once and reuse it. Like this
EventController lst=new EventController();
addEvent.addActionListener(lst);
addEvent.setActionCommand("add");
editEvent.addActionListener(lst);
editEvent.setActionCommand("edit");
deleteEvent.addActionListener(lst);
deleteEvent.setActionCommand("delete");
Add a method like this:
private void setListener(AbstractButton button, ActionListener listener, String command) {
button.addActionListener(listener);
button.setActionCommand(command);
}
Build a single EventController
instance.
EventController controller = new EventController();
Then, call it for each button:
setListener(addEvent, controller, "add");
...
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