Merge pull request #1589 from ProjectMirador/close-viewer-on-image-change

close viewer on tile change (cleans up existing tileSources)

src/components/OpenSeadragonViewer.js

@@ -38,11 +38,15 @@ class OpenSeadragonViewer extends Component {
   }
 
   /**
+   * When the tileSources change, make sure to close the OSD viewer.
    */
-  componentDidUpdate() {
+  componentDidUpdate(prevProps) {
     const { tileSources } = this.props;
+    if (prevProps.tileSources !== tileSources) {
+      this.viewer.close();
       tileSources.forEach(tileSource => this.addTileSource(tileSource));
     }
+  }
 
   /**
    */