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

1 vote336 views3 answers
How to add string to array in java
Java
0 vote316 views3 answers
Transcoder converter for python to java
Java
3 votes340 views4 answers
Round corner imageview android
Java
5 votes315 views2 answers
Android get screen width and height
Java
0 vote353 views1 answer
Syntax for new module creation in java
Java
0 vote313 views1 answer
Java swing on close
Java
0 vote362 views2 answers
Csv file data structure java
Java
0 vote346 views1 answer
Exoplayer how to put loader while video is still loading android java
Java
0 vote286 views1 answer
One space diagonally in java
Java
0 vote326 views1 answer
Common exceptions in java
Java