--- /dev/null
+/*
+ * Jalview - A Sequence Alignment Editor and Viewer ($$Version-Rel$$)
+ * Copyright (C) $$Year-Rel$$ The Jalview Authors
+ *
+ * This file is part of Jalview.
+ *
+ * Jalview is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, either version 3
+ * of the License, or (at your option) any later version.
+ *
+ * Jalview is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Jalview. If not, see <http://www.gnu.org/licenses/>.
+ * The Jalview Authors are detailed in the 'AUTHORS' file.
+ */
+package jalview.viewmodel;
+
+import java.beans.PropertyChangeSupport;
+
+public abstract class ViewportProperties
+{
+ protected PropertyChangeSupport changeSupport = new PropertyChangeSupport(
+ this);
+
+ public void addPropertyChangeListener(ViewportListenerI listener)
+ {
+ changeSupport.addPropertyChangeListener(listener);
+ }
+
+ public void removePropertyChangeListener(ViewportListenerI listener)
+ {
+ changeSupport.removePropertyChangeListener(listener);
+ }
+
+}