Fix MultiPage with multiple save() calls

 # Changelog
 
+## 1.3.17
+
+* Fix MultiPage with multiple save() calls
+
 ## 1.3.16
 
 * Add better debugPaint on Align Widget

@@ -39,7 +39,7 @@ class PdfObjectStream extends PdfObject {
   void _prepare() {
     super._prepare();
 
-    if (params.containsKey('/Filter')) {
+    if (params.containsKey('/Filter') && _data == null) {
       // The data is already in the right format
       _data = buf.output();
     } else if (pdfDocument.deflate != null) {

@@ -4,7 +4,7 @@ description: A pdf producer for Dart. It can create pdf files for both web or fl
 homepage: https://github.com/DavBfr/dart_pdf/tree/master/pdf
 repository: https://github.com/DavBfr/dart_pdf
 issue_tracker: https://github.com/DavBfr/dart_pdf/issues
-version: 1.3.16
+version: 1.3.17
 
 environment:
   sdk: ">=2.1.0 <3.0.0"

@@ -28,6 +28,7 @@ import 'type1_test.dart' as type1;
 import 'widget_basic_test.dart' as widget_basic;
 import 'widget_clip_test.dart' as widget_clip;
 import 'widget_container_test.dart' as widget_container;
+import 'widget_multipage_test.dart' as widget_multipage;
 import 'widget_table_test.dart' as widget_table;
 import 'widget_test.dart' as widget;
 import 'widget_text_test.dart' as widget_text;
@@ -47,6 +48,7 @@ void main() {
   widget_basic.main();
   widget_clip.main();
   widget_container.main();
+  widget_multipage.main();
   widget_table.main();
   widget_text.main();
   widget_theme.main();

+/*
+ * Copyright (C) 2017, David PHAM-VAN <dev.nfet.net@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import 'dart:io';
+
+import 'package:pdf/widgets.dart';
+import 'package:test/test.dart';
+
+List<Widget> lines = <Widget>[];
+
+void main() {
+  setUpAll(() {
+    for (int i = 0; i < 200; i++) {
+      lines.add(Text('Line $i'));
+    }
+  });
+
+  test('Pdf Widgets MultiPage', () {
+    Document.debug = true;
+
+    final Document pdf = Document();
+
+    pdf.addPage(MultiPage(build: (Context context) => lines));
+
+    final File file = File('widgets-multipage.pdf');
+    file.writeAsBytesSync(pdf.save());
+
+    final File file1 = File('widgets-multipage-1.pdf');
+    file1.writeAsBytesSync(pdf.save());
+  });
+
+  test('Pdf Widgets MonoPage', () {
+    Document.debug = true;
+
+    final Document pdf = Document();
+
+    pdf.addPage(Page(build: (Context context) => Column(children: lines)));
+
+    final File file = File('widgets-monopage.pdf');
+    file.writeAsBytesSync(pdf.save());
+
+    final File file1 = File('widgets-monopage-1.pdf');
+    file1.writeAsBytesSync(pdf.save());
+  });
+}