make tree select viewed group

ImageGallery/src/org/sleuthkit/autopsy/imagegallery/datamodel/grouping/GroupManager.java

@@ -703,12 +703,12 @@ public class GroupManager {
                     DrawableAttribute attributeOfCurrentGroup
                             = viewedKey.map(GroupKey::getAttribute)
                                     .orElse(null);
-
                     /* if no group or if groupbies are different or if data
                      * source != null and does not equal group */
                     if (viewedGroup.isPresent() == false
                         || (getDataSource() != null && notEqual(dataSourceOfCurrentGroup, getDataSource()))
                         || getGroupBy() != attributeOfCurrentGroup) {
+
                         //the current group should not be visible so ...
                         if (isNotEmpty(unSeenGroups)) {//  show then next unseen group 
                             controller.advance(GroupViewState.tile(unSeenGroups.get(0)));
@@ -718,7 +718,7 @@ public class GroupManager {
                         } else { //there are no groups,  clear the group area.
                             controller.advance(GroupViewState.tile(null));
                         }
-                    }   //else, the current group is for the given datasource, so just keep it in view.
+                    }
                 }
             } finally {
                 groupProgress.finish();

ImageGallery/src/org/sleuthkit/autopsy/imagegallery/gui/navpanel/GroupTree.java

@@ -38,6 +38,7 @@ import org.sleuthkit.autopsy.imagegallery.FXMLConstructor;
 import org.sleuthkit.autopsy.imagegallery.ImageGalleryController;
 import org.sleuthkit.autopsy.imagegallery.datamodel.DrawableAttribute;
 import org.sleuthkit.autopsy.imagegallery.datamodel.grouping.DrawableGroup;
+import org.sleuthkit.autopsy.imagegallery.datamodel.grouping.GroupViewState;
 
 /**
  * Shows path based groups as a tree and others kinds of groups as a flat list (
@@ -82,7 +83,12 @@ final public class GroupTree extends NavPanel<TreeItem<GroupTreeNode>> {
                 change.getAddedSubList().stream().forEach(this::insertGroup);
                 change.getRemoved().stream().forEach(this::removeFromTree);
             }
-            Platform.runLater(this::sortGroups);
+            Platform.runLater(() -> {
+                GroupTree.this.sortGroups();
+                Optional.ofNullable(getController().getViewState())
+                        .flatMap(GroupViewState::getGroup)
+                        .ifPresent(this::setFocusedGroup);
+            });
         });
 
         getGroupManager().getAnalyzedGroups().forEach(this::insertGroup);

ImageGallery/src/org/sleuthkit/autopsy/imagegallery/gui/navpanel/NavPanel.java

@@ -92,11 +92,10 @@ abstract class NavPanel<X> extends Tab {
 
         //keep selection in sync with controller
         controller.viewStateProperty().addListener(observable -> {
-            Platform.runLater(() -> {
-                Optional.ofNullable(controller.getViewState())
-                        .flatMap(GroupViewState::getGroup)
-                        .ifPresent(this::setFocusedGroup);
-            });
+            Platform.runLater(()
+                    -> Optional.ofNullable(controller.getViewState())
+                            .flatMap(GroupViewState::getGroup)
+                            .ifPresent(this::setFocusedGroup));
         });
 
         // notify controller about group selection in this view