fix 1.17

lib/container/boost_container.dart

@@ -41,7 +41,7 @@ enum ContainerLifeCycle {
 typedef BoostContainerLifeCycleObserver = void Function(
     ContainerLifeCycle state,
     BoostContainerSettings settings,
-);
+    );
 
 class BoostContainer extends Navigator {
   const BoostContainer({
@@ -161,6 +161,15 @@ class BoostContainerState extends NavigatorState {
   void initState() {
     super.initState();
     backPressedHandler = () => maybePop();
+    final String initRoute = widget.initialRoute ?? Navigator.defaultRouteName;
+    if (initRoute != null && routerHistory.isEmpty) {
+      routerHistory.addAll(
+          widget.onGenerateInitialRoutes(
+              this,
+              widget.initialRoute ?? Navigator.defaultRouteName
+          )
+      );
+    }
   }
 
   @override
@@ -177,7 +186,13 @@ class BoostContainerState extends NavigatorState {
 
   @override
   Future<bool> maybePop<T extends Object>([T result]) async {
+    if(routerHistory.isEmpty) {
+      pop(result);
+      return true;
+    }
+
     final Route<T> route = routerHistory.last as Route<T>;
+
     final RoutePopDisposition disposition = await route.willPop();
     if (mounted) {
     switch (disposition) {

lib/container/boost_page_route.dart

@@ -62,4 +62,9 @@ class BoostPageRoute<T> extends MaterialPageRoute<T> {
       return null;
     }
   }
+
+  @override
+  Future<RoutePopDisposition> willPop() {
+    return Future<RoutePopDisposition>.value(RoutePopDisposition.pop);
+  }
 }