#950 Resolves issue where message and event panels were aggregating across all selected now playing channels. (#951)

Co-authored-by: Denny <denny@denny-desktop>

src/main/java/io/github/dsheirer/module/HistoryModule.java

@@ -80,6 +80,15 @@ public abstract class HistoryModule<T> extends Module implements Listener<T>
         mBroadcaster.addListener(listener);
     }
 
+    /**
+     * Removes the listener from receiving items.
+     * @param listener to remove
+     */
+    public void removeListener(Listener<T> listener)
+    {
+        mBroadcaster.removeListener(listener);
+    }
+
     /**
      * Primary item receiver method.
      */

src/main/java/io/github/dsheirer/module/decode/event/DecodeEventPanel.java

@@ -139,7 +139,7 @@ public class DecodeEventPanel extends JPanel implements Listener<ProcessingChain
     {
         if(mCurrentEventHistory != null)
         {
-            mCurrentEventHistory.addListener(null);
+            mCurrentEventHistory.removeListener(mEventModel);
         }
 
         EventQueue.invokeLater(() -> {

src/main/java/io/github/dsheirer/module/decode/event/MessageActivityPanel.java

@@ -85,7 +85,7 @@ public class MessageActivityPanel extends JPanel implements Listener<ProcessingC
     {
         if(mCurrentMessageHistory != null)
         {
-            mCurrentMessageHistory.addListener(null);
+            mCurrentMessageHistory.removeListener(mMessageModel);
         }
 
         if(processingChain != null)