Merge pull request #525 from Hixie/yak3-routes-typed

Give type arguments to routes.

packages/flutter/lib/src/material/dialog.dart

@@ -115,8 +115,8 @@ class Dialog extends StatelessComponent {
   }
 }
 
-class _DialogRoute extends ModalRoute {
-  _DialogRoute({ Completer completer, this.child }) : super(completer: completer);
+class _DialogRoute<T> extends ModalRoute<T> {
+  _DialogRoute({ Completer<T> completer, this.child }) : super(completer: completer);
 
   final Widget child;
 

packages/flutter/lib/src/material/page.dart

@@ -36,7 +36,7 @@ class _MaterialPageTransition extends TransitionWithChild {
   }
 }
 
-class MaterialPageRoute extends ModalRoute {
+class MaterialPageRoute<T> extends ModalRoute<T> {
   MaterialPageRoute({
     this.builder,
     NamedRouteSettings settings: const NamedRouteSettings()

packages/flutter/lib/src/widgets/navigator.dart

@@ -5,10 +5,10 @@
 import 'framework.dart';
 import 'overlay.dart';
 
-abstract class Route {
+abstract class Route<T> {
   List<OverlayEntry> get overlayEntries;
   void didPush(OverlayState overlay, OverlayEntry insertionPoint) { }
-  void didPop(dynamic result) { }
+  void didPop(T result) { }
 
   /// The given route has been pushed onto the navigator after this route.
   /// Return true if the route before this one should be notified also. The
@@ -140,6 +140,9 @@ class NavigatorState extends State<Navigator> {
   /// Do not use this for ModalRoutes, or indeed anything other than
   /// StateRoutes. Doing so would cause very odd results, e.g. ModalRoutes would
   /// get confused about who is current.
+  ///
+  /// The type of the result argument, if provided, must match the type argument
+  /// of the class of the given route. (In practice, this is usually "dynamic".)
   void remove(Route route, [dynamic result]) {
     assert(_modal.contains(route));
     assert(route.overlayEntries.isEmpty);
@@ -155,6 +158,10 @@ class NavigatorState extends State<Navigator> {
 
   /// Removes the current route, notifying the observer (if any), and the
   /// previous routes (using [Route.didPopNext]).
+  ///
+  /// The type of the result argument, if provided, must match the type argument
+  /// of the class of the current route. (In practice, this is usually
+  /// "dynamic".)
   void pop([dynamic result]) {
     setState(() {
       // We use setState to guarantee that we'll rebuild, since the routes can't

packages/flutter/lib/src/widgets/routes.dart

@@ -23,6 +23,7 @@ class StateRoute extends Route {
   List<OverlayEntry> get overlayEntries => const <OverlayEntry>[];
 
   void didPop(dynamic result) {
+    assert(result == null);
     if (onPop != null)
       onPop();
   }
@@ -31,7 +32,7 @@ class StateRoute extends Route {
   bool didPopNext(Route nextRoute) => true;
 }
 
-abstract class OverlayRoute extends Route {
+abstract class OverlayRoute<T> extends Route<T> {
   List<WidgetBuilder> get builders => const <WidgetBuilder>[];
 
   List<OverlayEntry> get overlayEntries => _overlayEntries;
@@ -46,7 +47,7 @@ abstract class OverlayRoute extends Route {
   }
 
   // Subclasses shouldn't call this if they want to delay the finished() call.
-  void didPop(dynamic result) {
+  void didPop(T result) {
     finished();
   }
 
@@ -64,11 +65,15 @@ abstract class OverlayRoute extends Route {
   }
 }
 
-// TODO(abarth): Should we add a type for the result?
-abstract class TransitionRoute extends OverlayRoute {
-  TransitionRoute({ this.completer });
+abstract class TransitionRoute<T> extends OverlayRoute<T> {
+  TransitionRoute({
+    Completer<T> popCompleter,
+    Completer<T> transitionCompleter
+  }) : _popCompleter = popCompleter,
+       _transitionCompleter = transitionCompleter;
 
-  final Completer completer;
+  final Completer<T> _popCompleter;
+  final Completer<T> _transitionCompleter;
 
   Duration get transitionDuration;
   bool get opaque;
@@ -82,7 +87,7 @@ abstract class TransitionRoute extends OverlayRoute {
     return new Performance(duration: duration, debugLabel: debugLabel);
   }
 
-  dynamic _result;
+  T _result;
 
   void _handleStatusChanged(PerformanceStatus status) {
     switch (status) {
@@ -97,7 +102,6 @@ abstract class TransitionRoute extends OverlayRoute {
         break;
       case PerformanceStatus.dismissed:
         super.finished(); // clear the overlays
-        completer?.complete(_result);
         break;
     }
   }
@@ -109,9 +113,15 @@ abstract class TransitionRoute extends OverlayRoute {
     super.didPush(overlay, insertionPoint);
   }
 
-  void didPop(dynamic result) {
+  void didPop(T result) {
     _result = result;
     _performance.reverse();
+    _popCompleter?.complete(_result);
+  }
+
+  void finished() {
+    super.finished();
+    _transitionCompleter?.complete(_result);
   }
 
   String get debugLabel => '$runtimeType';
@@ -202,11 +212,11 @@ class ModalPosition {
   final double left;
 }
 
-abstract class ModalRoute extends TransitionRoute {
+abstract class ModalRoute<T> extends TransitionRoute<T> {
   ModalRoute({
-    Completer completer,
+    Completer<T> completer,
     this.settings: const NamedRouteSettings()
-  }) : super(completer: completer);
+  }) : super(popCompleter: completer);
 
   // The API for general users of this class
 
@@ -263,7 +273,7 @@ abstract class ModalRoute extends TransitionRoute {
     super.didPush(overlay, insertionPoint);
   }
 
-  void didPop(dynamic result) {
+  void didPop(T result) {
     assert(_isCurrent);
     _isCurrent = false;
     super.didPop(result);