diff --git a/packages/flutter_tools/lib/src/vmservice.dart b/packages/flutter_tools/lib/src/vmservice.dart
index e9df65d2962..332f3520988 100644
--- a/packages/flutter_tools/lib/src/vmservice.dart
+++ b/packages/flutter_tools/lib/src/vmservice.dart
@@ -1124,7 +1124,8 @@ class FlutterView extends ServiceObject {
       // launch errors.
       if (event.kind == ServiceEvent.kIsolateRunnable) {
         printTrace('Isolate is runnable.');
-        completer.complete(null);
+        if (!completer.isCompleted)
+          completer.complete(null);
       }
     });
     await owner.vm.runInView(viewId,