added progressCallback to file upload

for parse-community#366

Author: fischerscode

lib/src/objects/parse_file.dart

@@ -50,15 +50,16 @@ class ParseFile extends ParseFileBase {
     final Directory tempPath = await getTemporaryDirectory();
     file = File('${tempPath.path}/$name');
     await file.create();
-    final Response<List<int>> response = await _client.get<List<int>>(url, options: Options(responseType: ResponseType.bytes));
+    final Response<List<int>> response = await _client.get<List<int>>(url,
+        options: Options(responseType: ResponseType.bytes));
     await file.writeAsBytes(response.data);
 
     return this;
   }
 
   /// Uploads a file to Parse Server
   @override
-  Future<ParseResponse> upload() async {
+  Future<ParseResponse> upload({ProgressCallback progressCallback}) async {
     if (saved) {
       //Creates a Fake Response to return the correct result
       final Map<String, String> response = <String, String>{
@@ -80,8 +81,12 @@ class ParseFile extends ParseFileBase {
     try {
       final String uri = _client.data.serverUrl + '$_path';
       final List<int> body = await file.readAsBytes();
-      final Response<String> response = await _client.post<String>(uri,
-          options: Options(headers: headers), data: body);
+      final Response<String> response = await _client.post<String>(
+        uri,
+        options: Options(headers: headers),
+        data: body,
+        onSendProgress: progressCallback,
+      );
       if (response.statusCode == 201) {
         final Map<String, dynamic> map = json.decode(response.data);
         url = map['url'].toString();

lib/src/objects/parse_file_base.dart

@@ -41,7 +41,7 @@ abstract class ParseFileBase extends ParseObject {
   }
 
   /// Uploads a file to Parse Server
-  Future<ParseResponse> upload();
+  Future<ParseResponse> upload({ProgressCallback progressCallback});
 
   Future<ParseFileBase> download();
 }

lib/src/objects/parse_file_web.dart

@@ -31,7 +31,7 @@ class ParseWebFile extends ParseFileBase {
   }
 
   @override
-  Future<ParseResponse> upload() async {
+  Future<ParseResponse> upload({ProgressCallback progressCallback}) async {
     if (saved) {
       //Creates a Fake Response to return the correct result
       final Map<String, String> response = <String, String>{
@@ -53,8 +53,12 @@ class ParseWebFile extends ParseFileBase {
     };
     try {
       final String uri = _client.data.serverUrl + '$_path';
-      final Response<String> response = await _client.post<String>(uri,
-          options: Options(headers: headers), data: file);
+      final Response<String> response = await _client.post<String>(
+        uri,
+        options: Options(headers: headers),
+        data: file,
+        onSendProgress: progressCallback,
+      );
       if (response.statusCode == 201) {
         final Map<String, dynamic> map = json.decode(response.data);
         url = map['url'].toString();