cleanup code

lib/helpers/api_helper.dart

@@ -27,7 +27,7 @@ Future<dynamic> requestAPI(String path, method,
   if (token != null) {
     headers["Token"] = token;
   }
-  if (devInfo != null && devInfo.deviceID != null && deviceName != null) {
+  if (devInfo.deviceID != null) {
     headers["Device"] = devInfo.deviceID ?? "" + ":" + deviceName;
   }
   headers["Project-ID"] = Config.instance.reportProjectID;
@@ -148,8 +148,8 @@ typedef OnDownloadDone(File file);
 // if token is null
 Future<dynamic> requestDownload(String path, method,
     {dynamic payload,
-    required String token,
-    required String url,
+    required String? token,
+    required String? url,
     required String filePath,
     OnDownloadDone? onDownloadDone}) async {
   DeviceInfoPlugin deviceInfo = DeviceInfoPlugin();
@@ -187,7 +187,7 @@ Future<dynamic> requestDownload(String path, method,
       fileName = cd.substring(cd.indexOf("=") + 1);
     }
 
-    var file = filePath + "/" + fileName;
+    // var file = filePath + "/" + fileName;
     var fileSave = new File(filePath + "/" + fileName);
     response.listen((d) => _downloadData.addAll(d), onDone: () async {
       await fileSave.writeAsBytes(_downloadData);

lib/helpers/firebase_helper.dart

@@ -62,7 +62,7 @@ Future<String> uploadStorage(String path, File? file,
 }
 
 Future<void> deleteStorageFromUrls(List<String?> urls) async {
-  if (urls == null) return;
+  if (urls.isEmpty) return;
   for (int i = 0; i < urls.length; i++) {
     if (urls[i] == null) return;
     await deleteStorageFromUrl(urls[i]!);

lib/helpers/network_connectivity.dart

@@ -51,7 +51,7 @@ class NetworkConnectivity {
       }
     }
 
-    if (_controller != null && !_controller.isClosed)
+    if (!_controller.isClosed)
       _controller.sink.add({"isOnline": isOnline});
   }