Android on change class event

//It's not possible directly. However, you can make your field private, add getters and setters, and create a method of adding listeners (this is called the Observer pattern):

interface ConnectionBooleanChangedListener {
    public void OnMyBooleanChanged();
}

public class Connect { 
     private static boolean myBoolean;
     private static List<ConnectionBooleanChangedListener> listeners = new ArrayList<ConnectionBooleanChangedListener>();

     public static boolean getMyBoolean() { return myBoolean; }

     public static void setMyBoolean(boolean value) {
         myBoolean = value;

         for (ConnectionBooleanChangedListener l : listeners) {
             l.OnMyBooleanChanged();
         }
     }

     public static void addMyBooleanListener(ConnectionBooleanChangedListener l) {
         listeners.add(l);
     }
}

//Then, wherever you want to listen to changes of the boolean, you can register a listener:

Connect.addMyBooleanListener(new ConnectionBooleanChangedListener() {
    @Override
    public void OnMyBooleanChanged() {
        // do something
    }
});

//Adding a method to remove listeners is left as an exercise. Obviously, for this to work, you need to make sure that myBoolean is only changed via setMyBoolean, even inside of Connect.

Source: stackoverflow.com

Similar codes

2 votes170 views1 answer
Android studio start another activity
Java
3 votes177 views2 answers
Java how to change the length of an array
Java
18 votes227 views2 answers
How to get int from string java
Java
0 vote170 views3 answers
HashMap to Pojo
Java
0 vote195 views1 answer
Java domande risposta multipla
Java
0 vote201 views1 answer
Java optional to collection
Java
0 vote188 views1 answer
Java windowbuilder multiple monitors windowed mode
Java
2 votes181 views1 answer
Jlabel on the center of a jpanel
Java
0 vote161 views1 answer
Android studio layout bring to front
Java
0 vote202 views1 answer
Pdf intent does not have permission to launch
Java