add clearGenomeStatsCache function and clear and reload the statistisc when the chromosome is changed

Author: timeu

src/main/java/at/gmi/nordborglab/widgets/geneviewer/client/GeneViewer.java

@@ -112,7 +112,6 @@ public enum SHOW_RANGE_SELECTOR  {None,Bottom,Top};
 	protected DataTable stackableGenomeStatsCache = null;
 	protected HashMap<GenomeStat,DataTable> nonstackableGenomeStatsCache = new HashMap<GenomeStat,DataTable>();
 	protected Dygraphs.Options options = Dygraphs.Options.create();
-	protected DataTable statisticsDataTable;
 	protected int width_offset = 31;
 
 	private final ScheduledCommand layoutCmd = new ScheduledCommand() {
@@ -194,6 +193,8 @@ public void setViewRegion(int start, int end) {
 		this.viewEnd = end;
 		if (processing.isLoaded()) {
 			processing.getInstance().setViewRegion(start, end);
+			if (showStatsBand)
+				drawStatistics();
 		}
 	}
 
@@ -213,7 +214,14 @@ public void setRangeSelectorPosition(SHOW_RANGE_SELECTOR show_range_selector) {
 
 
 	public void setChromosome(String chromosome) {
+		boolean redrawStats = false;
+		if (chromosome != null && !chromosome.equals(this.chromosome))
+			redrawStats = true;
 		this.chromosome = chromosome;
+		if (redrawStats) {
+			clearGenomeStatsCache();
+			loadAndDisplayGenomeStats(true);
+		}
 	}
 
 	public void updateZoom(Integer start,Integer end) {
@@ -756,4 +764,9 @@ private void scheduledLayout() {
 	      Scheduler.get().scheduleDeferred(layoutCmd);
 	    }
 	}
+	
+	private void clearGenomeStatsCache() {
+		stackableGenomeStatsCache = null;
+		nonstackableGenomeStatsCache.clear();
+	}
 }