fix for deleting the last layer in a geopackage not reloading the geopackage detail view

Author: jclark118

mapcache/src/main/java/mil/nga/mapcache/GeoPackageMapFragment.java

@@ -1028,7 +1028,7 @@ public void onClick(boolean active, GeoPackageTable table) {
             }
         };
 
-        // Listener to forward a button click layer detail page to the appropriate dialog function
+        // (Delete) Listener to forward a button click layer detail page to the appropriate dialog function
         DetailActionListener detailActionListener = new DetailActionListener(){
             @Override
             public void onClick(View view, int actionType, String gpName, String layerName) {
@@ -1193,13 +1193,24 @@ public void onDeleteLayer(String gpName, String layerName){
         // layers live data is updated
 
 
+        // Get current geopackage database object in case removing layer deletes the last layer of the gp
+        GeoPackageDatabase currentDb = geoPackageViewModel.getGeoByName(gpName);
+        GeoPackageTable removableTable = currentDb.getTableByName(layerName);
 
         // First remove it from the active layers
         geoPackageViewModel.removeActiveLayer(gpName, layerName);
         // Ask the repository to delete the layer
         GeoPackageDatabase db = geoPackageViewModel.removeLayerFromGeo(gpName, layerName);
         if(db != null){
             createGeoPackageDetailAdapter(db);
+        } else{
+            // If the layer that was deleted was the last one in the geopackage, the remove layer
+            // method will return null.  In that case, use our original DB object with the deleted
+            // layer to populate the detail adapter view
+            if(currentDb != null && removableTable != null) {
+                currentDb.remove(removableTable);
+                createGeoPackageDetailAdapter(currentDb);
+            }
         }
     }
 

mapcache/src/main/java/mil/nga/mapcache/data/GeoPackageDatabases.java

@@ -338,6 +338,10 @@ public void removeTable(GeoPackageTable table, boolean preserveOverlays) {
         if (database != null) {
             database.remove(table);
             removeTableFromPreferences(table);
+            if (database.isEmpty()) {
+                databases.remove(database.getDatabase());
+                removeDatabaseFromPreferences(database.getDatabase(), preserveOverlays);
+            }
             if (!preserveOverlays && table.getType() == GeoPackageTableType.FEATURE) {
                 List<GeoPackageFeatureOverlayTable> deleteFeatureOverlays = new ArrayList<GeoPackageFeatureOverlayTable>();
                 int count = 0;