Fixed analysis warnings in notus

packages/notus/analysis_options.yaml

   strong-mode:
     implicit-casts: false
     implicit-dynamic: false
-    
+
 # Lint rules and documentation, see http://dart-lang.github.io/linter/lints
 linter:
   rules:

packages/notus/lib/src/convert/markdown.dart

   String _writeLine(String text, NotusStyle style) {
     StringBuffer buffer = new StringBuffer();
     if (style.contains(NotusAttribute.heading)) {
-      _writeAttribute(buffer, style.get(NotusAttribute.heading));
+      _writeAttribute(buffer, style.get<int>(NotusAttribute.heading));
     }
 
     // Write the text itself
     } else if (attribute == NotusAttribute.italic) {
       _writeItalicTag(buffer);
     } else if (attribute.key == NotusAttribute.link.key) {
-      _writeLinkTag(buffer, attribute, close: close);
+      _writeLinkTag(buffer, attribute as NotusAttribute<String>, close: close);
     } else if (attribute.key == NotusAttribute.heading.key) {
-      _writeHeadingTag(buffer, attribute);
+      _writeHeadingTag(buffer, attribute as NotusAttribute<int>);
     } else if (attribute.key == NotusAttribute.block.key) {
-      _writeBlockTag(buffer, attribute, close: close);
+      _writeBlockTag(buffer, attribute as NotusAttribute<String>, close: close);
     } else {
       throw new ArgumentError('Cannot handle $attribute');
     }

packages/notus/lib/src/document.dart

     _loadDocument(_delta);
   }
 
-  NotusDocument.fromJson(dynamic data)
+  NotusDocument.fromJson(List data)
       : _heuristics = NotusHeuristics.fallback,
         _delta = Delta.fromJson(data) {
     _loadDocument(_delta);

packages/notus/lib/src/document/attributes.dart

   /// Embed style attribute.
   static const embed = const EmbedAttributeBuilder._();
 
-  factory NotusAttribute._fromKeyValue(String key, T value) {
+  static NotusAttribute _fromKeyValue(String key, dynamic value) {
     if (!_registry.containsKey(key))
       throw new ArgumentError.value(
           key, 'No attribute with key "$key" registered.');
       new NotusAttribute<T>._(key, scope, value);
 
   @override
-  bool operator ==(other) {
+  bool operator ==(Object other) {
     if (identical(this, other)) return true;
     if (other is! NotusAttribute<T>) return false;
     NotusAttribute<T> typedOther = other;
 
   final Map<String, NotusAttribute> _data;
 
-  static NotusStyle fromJson(Map data) {
+  static NotusStyle fromJson(Map<String, dynamic> data) {
     if (data == null) return new NotusStyle();
 
-    final result = data.map((key, value) {
-      var attr = new NotusAttribute._fromKeyValue(key, value);
+    final result = data.map((String key, dynamic value) {
+      var attr = NotusAttribute._fromKeyValue(key, value);
       return new MapEntry<String, NotusAttribute>(key, attr);
     });
     return new NotusStyle._(result);
   /// [attribute].
   bool containsSame(NotusAttribute attribute) {
     assert(attribute != null);
-    return get(attribute) == attribute;
+    return get<dynamic>(attribute) == attribute;
   }
 
   /// Returns value of specified attribute [key] in this set.
   /// Returns JSON-serializable representation of this style.
   Map<String, dynamic> toJson() => _data.isEmpty
       ? null
-      : _data.map(
-          (_, value) => new MapEntry<String, dynamic>(value.key, value.value));
+      : _data.map<String, dynamic>((String _, NotusAttribute value) =>
+          new MapEntry<String, dynamic>(value.key, value.value));
 
   @override
-  bool operator ==(other) {
+  bool operator ==(Object other) {
     if (identical(this, other)) return true;
     if (other is! NotusStyle) return false;
     NotusStyle typedOther = other;

packages/notus/lib/src/document/block.dart

       while (child != line) {
         child.unlink();
         before.add(child);
-        child = this.first;
+        child = this.first as LineNode;
       }
       line.unlink();
       insertBefore(line);

packages/notus/lib/src/document/leaf.dart

     assert(index >= 0 && index <= length);
     if (index == 0) return this;
     if (index == length && isLast) return null;
-    if (index == length && !isLast) return next;
+    if (index == length && !isLast) return next as LeafNode;
 
     String text = _value;
     _value = text.substring(0, index);
   }
 
   @override
-  LineNode get parent => super.parent;
+  LineNode get parent => super.parent as LineNode;
 
   @override
   int get length => _value.length;

packages/notus/lib/src/document/line.dart

     if (isLast) {
       if (parent is BlockNode) {
         if (parent.isLast) return null;
-        return (parent.next is BlockNode)
+        LineNode line = (parent.next is BlockNode)
             ? (parent.next as BlockNode).first
             : parent.next;
+        return line;
       } else
         return null;
     } else {
-      return (next is BlockNode) ? (next as BlockNode).first : next;
+      LineNode line = (next is BlockNode) ? (next as BlockNode).first : next;
+      return line;
     }
   }
 
       result = result.mergeAll(node.style);
       int pos = node.length - data.offset;
       while (!node.isLast && pos < local) {
-        node = node.next;
+        node = node.next as LeafNode;
         _handle(node.style);
         pos += node.length;
       }

packages/notus/lib/src/document/node.dart

 
     if (isEmpty) {
       assert(index == 0);
-      Node node = defaultChild;
+      T node = defaultChild;
       add(node);
       node.insert(index, value, style);
     } else {

packages/notus/lib/src/heuristics/delete_rules.dart

 
   Map<String, dynamic> _unsetAttributes(Map<String, dynamic> attributes) {
     if (attributes == null) return null;
-    return attributes.map((key, value) => new MapEntry(key, null));
+    return attributes.map<String, dynamic>((String key, dynamic value) =>
+        new MapEntry<String, dynamic>(key, null));
   }
 }
 

packages/notus/lib/src/heuristics/insert_rules.dart

     final target = iter.next();
 
     if (target.data.startsWith('\n')) {
-      Map<String, dynamic> resetStyle = null;
+      Map<String, dynamic> resetStyle;
       if (target.attributes != null &&
           target.attributes.containsKey(NotusAttribute.heading.key)) {
         resetStyle = NotusAttribute.heading.unset.toJson();
       }
     }
 
-    Map<String, dynamic> resetStyle = null;
-    Map<String, dynamic> blockStyle = null;
+    Map<String, dynamic> resetStyle;
+    Map<String, dynamic> blockStyle;
     if (lineStyle != null) {
       if (lineStyle.containsKey(NotusAttribute.heading.key)) {
         resetStyle = NotusAttribute.heading.unset.toJson();

packages/notus/test/convert/markdown_test.dart

 
 final doc =
     r'[{"insert":"Zefyr"},{"insert":"\n","attributes":{"heading":1}},{"insert":"Soft and gentle rich text editing for Flutter applications.","attributes":{"i":true}},{"insert":"\nZefyr is an "},{"insert":"early preview","attributes":{"b":true}},{"insert":" open source library.\nDocumentation"},{"insert":"\n","attributes":{"heading":3}},{"insert":"Quick Start"},{"insert":"\n","attributes":{"block":"ul"}},{"insert":"Data format and Document Model"},{"insert":"\n","attributes":{"block":"ul"}},{"insert":"Style attributes"},{"insert":"\n","attributes":{"block":"ul"}},{"insert":"Heuristic rules"},{"insert":"\n","attributes":{"block":"ul"}},{"insert":"Clean and modern look"},{"insert":"\n","attributes":{"heading":2}},{"insert":"Zefyr’s rich text editor is built with simplicity and flexibility in mind. It provides clean interface for distraction-free editing. Think Medium.com-like experience.\nimport ‘package:flutter/material.dart’;"},{"insert":"\n","attributes":{"block":"code"}},{"insert":"import ‘package:notus/notus.dart’;"},{"insert":"\n\n","attributes":{"block":"code"}},{"insert":"void main() {"},{"insert":"\n","attributes":{"block":"code"}},{"insert":" print(“Hello world!”);"},{"insert":"\n","attributes":{"block":"code"}},{"insert":"}"},{"insert":"\n","attributes":{"block":"code"}}]';
-final delta = Delta.fromJson(json.decode(doc));
+final delta = Delta.fromJson(json.decode(doc) as List);
 
 final expectedMarkdown = '''
 # Zefyr

packages/notus/test/document/attributes_test.dart

 void main() {
   group('$NotusStyle', () {
     test('get', () {
-      var attrs = NotusStyle.fromJson({'block': 'ul'});
+      var attrs = NotusStyle.fromJson(<String, dynamic>{'block': 'ul'});
       var attr = attrs.get(NotusAttribute.block);
       expect(attr, NotusAttribute.ul);
     });

packages/notus/test/document_test.dart

     test('json serialization', () {
       final original = dartconfDoc();
       final jsonData = json.encode(original);
-      final doc = NotusDocument.fromJson(json.decode(jsonData));
+      final doc = NotusDocument.fromJson(json.decode(jsonData) as List);
       expect(doc.toDelta(), original.toDelta());
       expect(json.encode(doc), jsonData);
     });

packages/zefyr/lib/src/widgets/scope.dart

 
 import 'controller.dart';
 import 'cursor_timer.dart';
+import 'editor.dart';
 import 'image.dart';
 import 'render_context.dart';
-
+import 'view.dart';
+
+/// Provides access to shared state of [ZefyrEditor] or [ZefyrView].
+///
+/// A scope object can be created by an editable widget like [ZefyrEditor] in
+/// which case it provides access to editing state, including focus nodes,
+/// selection and such. Editable scope can be created using
+/// [ZefyrScope.editable] constructor.
+///
+/// If a scope object is created by a view-only widget like [ZefyrView] then
+/// it only provides access to [imageDelegate].
+///
+/// Can be retrieved using [ZefyrScope.of].
 class ZefyrScope extends ChangeNotifier {
+  /// Creates a view-only scope.
+  ///
+  /// Normally used in [ZefyrView].
   ZefyrScope.view({@required ZefyrImageDelegate imageDelegate})
       : assert(imageDelegate != null),
         isEditable = false,
         _imageDelegate = imageDelegate;
 
+  /// Creates editable scope.
+  ///
+  /// Normally used in [ZefyrEditor].
   ZefyrScope.editable({
     @required ZefyrController controller,
     @required ZefyrImageDelegate imageDelegate,
     _focusNode.addListener(_handleFocusChange);
   }
 
+  static ZefyrScope of(BuildContext context) {
+    final ZefyrScopeAccess widget =
+        context.inheritFromWidgetOfExactType(ZefyrScopeAccess);
+    return widget.scope;
+  }
+
   ZefyrImageDelegate _imageDelegate;
   ZefyrImageDelegate get imageDelegate => _imageDelegate;
   set imageDelegate(ZefyrImageDelegate value) {
   /// objects which are not dependent on editing flow, e.g. [imageDelegate].
   final bool isEditable;
 
-  static ZefyrScope of(BuildContext context) {
-    final ZefyrScopeAccess widget =
-        context.inheritFromWidgetOfExactType(ZefyrScopeAccess);
-    return widget.scope;
-  }
-
   set toolbarFocusNode(FocusNode node) {
     assert(isEditable);
     assert(!_disposed || node == null);