Resolved conflicts

Author: SriramKiranSenthilkumar

lib/main.dart

@@ -11,9 +11,7 @@ class ChartApp extends StatelessWidget {
   Widget build(BuildContext context) {
     return MaterialApp(
       title: 'Chart Demo',
-      theme: ThemeData(
-        primarySwatch: Colors.blue
-      ),
+      theme: ThemeData(primarySwatch: Colors.blue),
       home: MyHomePage(),
     );
   }
@@ -28,6 +26,14 @@ class MyHomePage extends StatefulWidget {
 }
 
 class _MyHomePageState extends State<MyHomePage> {
+  TooltipBehavior _tooltipBehavior;
+
+  @override
+  void initState() {
+    _tooltipBehavior = TooltipBehavior(enable: true);
+    super.initState();
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
@@ -63,29 +69,25 @@ class _MyHomePageState extends State<MyHomePage> {
                 }
               },
                 primaryXAxis: DateTimeAxis(
-                  interval: 30,
-                  intervalType: DateTimeIntervalType.days
-                ),
+                    interval: 30, intervalType: DateTimeIntervalType.days),
                 // Enable tooltip
-                tooltipBehavior: TooltipBehavior(enable: true),
+                tooltipBehavior: _tooltipBehavior,
                 series: <ChartSeries<SalesData, DateTime>>[
                   LineSeries<SalesData, DateTime>(
-                      enableTooltip: true,
-                      dataSource: <SalesData>[
-                        SalesData(DateTime(2020, 01, 31), 35),
-                        SalesData(DateTime(2020, 02, 28), 28),
-                        SalesData(DateTime(2020, 03, 31), 34),
-                        SalesData(DateTime(2020, 04, 30), 32),
-                        SalesData(DateTime(2020, 05, 31), 40)
-                      ],
-                      xValueMapper: (SalesData sales, _) => sales.date,
-                      yValueMapper: (SalesData sales, _) => sales.sales,
+                    enableTooltip: true,
+                    dataSource: <SalesData>[
+                      SalesData(DateTime(2020, 01, 31), 35),
+                      SalesData(DateTime(2020, 02, 28), 28),
+                      SalesData(DateTime(2020, 03, 31), 34),
+                      SalesData(DateTime(2020, 04, 30), 32),
+                      SalesData(DateTime(2020, 05, 31), 40)
+                    ],
+                    xValueMapper: (SalesData sales, _) => sales.date,
+                    yValueMapper: (SalesData sales, _) => sales.sales,
                   )
-                ]
-            ),
+                ]),
           ),
-        )
-    );
+        ));
   }
 }
 
@@ -94,4 +96,4 @@ class SalesData {
 
   final DateTime date;
   final double sales;
-}
+}