Timetable better week swipe, timetable performance upgrade

lib/screen/pages/timetable/timetable.dart

@@ -13,6 +13,8 @@ class Timetable extends StatefulWidget {
 }
 
 class _TimetableState extends State<Timetable> {
+  bool draggable = true;
+
   @override
   void initState() {
     super.initState();
@@ -36,14 +38,19 @@ class _TimetableState extends State<Timetable> {
             Expanded(
               child: GestureDetector(
                 child: WeekView(value),
-                //onDoubleTap: () => timetable.nearest(),
-                onHorizontalDragEnd: (details) {
-                  if(details.primaryVelocity! < 0) {
-                    timetable.switchWeek();
-                  } else {
+                onHorizontalDragUpdate: (details) {
+                  if(!draggable) return;
+                  if(details.delta.dx > 5) {
+                    draggable = false;
                     timetable.switchWeek(previous: true);
+                  } else if(details.delta.dx < 5) {
+                    draggable = false;
+                    timetable.switchWeek();
                   }
                 },
+                onHorizontalDragEnd: (details) {
+                  draggable = true;
+                },
               ),
             ),