Move compass to separate class

mobile/src/com/cradle/iitc_mobile/compass/Compass.java

@@ -0,0 +1,39 @@
+package com.cradle.iitc_mobile.compass;
+
+import java.util.ArrayList;
+
+public abstract class Compass
+{
+    private final ArrayList<CompassListener> mListeners = new ArrayList<CompassListener>();
+    private boolean mStarted = false;
+
+    protected void publishOrientation(final float x, final float y, final float z)
+    {
+        for (final CompassListener listener : mListeners)
+            listener.onCompassChanged(x, y, z);
+    }
+
+    protected abstract void onStart();
+
+    protected abstract void onStop();
+
+    public void registerListener(final CompassListener listener)
+    {
+        mListeners.add(listener);
+        if (!mStarted)
+        {
+            onStart();
+            mStarted = true;
+        }
+    }
+
+    public void unregisterListener(final CompassListener listener)
+    {
+        mListeners.remove(listener);
+        if (mListeners.size() == 0)
+        {
+            onStop();
+            mStarted = false;
+        }
+    }
+}