update source and fire event only if features added

src/ol/interaction/DragAndDrop.js

@@ -147,9 +147,6 @@ class DragAndDrop extends Interaction {
         featureProjection: projection,
       });
       if (features && features.length > 0) {
-        break;
-      }
-    }
         if (this.source_) {
           this.source_.clear();
           this.source_.addFeatures(features);
@@ -162,6 +159,9 @@ class DragAndDrop extends Interaction {
             projection
           )
         );
+        break;
+      }
+    }
   }
 
   /**