My problem is that when I change the value from a property of my model the PropertyChangeSupport
fires but the PropertyChangeListener
in the view is never reached.
So I guess I am making something wrong by adding the listener.
Any kind of input is appreciated.
package stackOverflow.allInOne;
import java.awt.FlowLayout;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import static java.lang.System.getProperty;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
public class AllInOne {
public static void main(String[] args) {
final Model Model = new Model();
final Controller Controller = new Controller(Model);
Controller.initializeView();
}
}
class View extends JFrame{
private final Model model;
private final Controller controller;
JTextField fldAny;
JButton btnAny;
public View(Model model, Controller controller) {
super("SBB app");
this.model = model;
this.controller = controller;
}
public void createAndShow() {
initializeComponents();
JPanel contents = layoutComponents();
addActionEvents();
addPropertyChangeListeners();
add(contents);
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
pack();
setVisible(true);
}
private void initializeComponents() {
fldAny = new JTextField("----------");
btnAny = new JButton("klick me");
}
private JPanel layoutComponents() {
JPanel anyPanel = new JPanel(new FlowLayout());
anyPanel.add(fldAny);
anyPanel.add(btnAny);
return anyPanel;
}
private void addActionEvents() {
fldAny.getDocument().addDocumentListener(new DocumentListener() {
@Override
public void changedUpdate(DocumentEvent e) {
change();
}
@Override
public void insertUpdate(DocumentEvent e) {
change();
}
@Override
public void removeUpdate(DocumentEvent e) {
change();
}
public void change() {
System.out.println("action event fired");
controller.setNewValue(fldAny.getText());
}
});
}
private void addPropertyChangeListeners() {
PropertyChangeListener myListener = new MyPropertyChangeListener(this);
List<Model2> xx = model.getAllModel2();
for(Model2 x : xx){
x.addPropertyChangeListener(Model2.BTN_TXT, myListener);
}
}
}
class MyPropertyChangeListener implements PropertyChangeListener{
private View view;
public MyPropertyChangeListener(View view) {
this.view = view;
}
@Override
public void propertyChange(PropertyChangeEvent evt) {
System.out.println(evt);
System.out.println("Receved the fire");
view.btnAny.setText(view.btnAny.getText() + "1");
}
}
class Model2{
private String fldText;
private String btnText;
public static final String BTN_TXT = "btnText";
private final PropertyChangeSupport pcs = new PropertyChangeSupport(this);
Model2(String fldText, String btnText) {
this.fldText = fldText;
this.btnText = btnText;
}
public void setFldText(String fldText) {
this.fldText = fldText;
}
public String getFldText() {
return fldText;
}
public String getBtnText() {
return btnText;
}
public void setBtnText(String btnText) {
System.err.println("Model fires");
pcs.firePropertyChange(BTN_TXT, btnText, this.btnText = btnText);
}
public void addPropertyChangeListener(PropertyChangeListener listener) {
pcs.addPropertyChangeListener(listener);
}
public void addPropertyChangeListener(String propertyName, PropertyChangeListener listener) {
System.out.println("Listener wird zu " +listener.toString() + " hinzugefügt mit property " + propertyName);
pcs.addPropertyChangeListener(propertyName, listener);
final Object value = getProperty(propertyName);
listener.propertyChange(new PropertyChangeEvent(this, propertyName,
value, value));
}
public void removePropertyChangeListener(PropertyChangeListener listener) {
pcs.removePropertyChangeListener(listener);
}
public void removePropertyChangeListener(String propertyName, PropertyChangeListener listener) {
pcs.removePropertyChangeListener(propertyName, listener);
}
public PropertyChangeListener[] getPropertyChangeListeners() {
return pcs.getPropertyChangeListeners();
}
public PropertyChangeListener[] getPropertyChangeListeners(String propertyName) {
return pcs.getPropertyChangeListeners(propertyName);
}
}
class Model {
private List<Model2> model2List = new ArrayList<Model2>();
public Model() {
model2List.add(new Model2("fldText","btnText"));
}
public Model2 getSelectdModel2(){
return model2List.get(0);
}
List<Model2> getAllModel2() {
return model2List;
}
}
class Controller {
private final Model model;
public Controller(Model model) {
this.model = model;
}
public void initializeView() {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
View view = new View(model, Controller.this);
view.createAndShow();
}
});
}
void setNewValue(String text) {
System.out.println("Controller sets new value");
model.getSelectdModel2().setBtnText(text);
}
}
I am currently getting the following output when I start the Application:
Listener wird zu stackOverflow.allInOne.MyPropertyChangeListener@cee47f1 hinzugefügt mit property btnText java.beans.PropertyChangeEvent[propertyName=btnText; oldValue=null; newValue=null; propagationId=null; source=stackOverflow.allInOne.Model2@6fb525d8] Receved the fire
So I am a little bit confused why I am getting this fire because I am setting the value of the btnTxt before I am adding the listener to it. Anyway if I change the text in the field then I am getting the following output:
action event fired Controller sets new value Model fires
So as mentioned in my initial question it seems to my that
x.addPropertyChangeListener(Model2.BTN_TXT, myListener);
Doesn't always work.
And the error was so simple. The Fire and the listener worked. The only problem was that the propertychangesupport never really fired because I was passing every time the same value:
pcs.firePropertyChange(BTN_TXT, btnText, this.btnText = btnText);
While the secound parameter is supposed to be the old value and the third the new one. Because I was already assigning my old variable with the new value
this.btnText = btnText
the pcs thought the values where the same and didn't changed anything.So the right example would be:
pcs.firePropertyChange(BTN_TXT, this.btnText, btnText); this.btnText = btnText;
Thanks for the help