Added the possibility to have multiple slivers as child, and even sti…

…cky header (currently one one inside one other works).

Also solves letsar#62

example/lib/examples/double_list.dart

@@ -0,0 +1,63 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_sticky_header/flutter_sticky_header.dart';
+
+import '../common.dart';
+
+class DoubleListExample extends StatelessWidget {
+  const DoubleListExample({
+    Key? key,
+  }) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return AppScaffold(
+      title: 'List Example',
+      slivers: [
+        _StickyHeaderList(index: 0),
+        _StickyHeaderList(index: 1),
+        _StickyHeaderList(index: 2),
+        _StickyHeaderList(index: 3),
+      ],
+    );
+  }
+}
+
+class _StickyHeaderList extends StatelessWidget {
+  const _StickyHeaderList({
+    Key? key,
+    this.index,
+  }) : super(key: key);
+
+  final int? index;
+
+  @override
+  Widget build(BuildContext context) {
+    return SliverStickyHeader(
+      header: Header(index: index),
+      slivers: [
+        SliverList(
+          delegate: SliverChildBuilderDelegate(
+            (context, i) => ListTile(
+              leading: CircleAvatar(
+                child: Text('$index'),
+              ),
+              title: Text('List tile #$i'),
+            ),
+            childCount: 6,
+          ),
+        ),
+        SliverList(
+          delegate: SliverChildBuilderDelegate(
+            (context, i) => ListTile(
+              trailing: CircleAvatar(
+                child: Text('$index'),
+              ),
+              title: Text('List tile #$i'),
+            ),
+            childCount: 3,
+          ),
+        ),
+      ],
+    );
+  }
+}

example/lib/examples/indented_header.dart

@@ -0,0 +1,89 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_sticky_header/flutter_sticky_header.dart';
+
+import '../common.dart';
+
+class IndentedHeaderExample extends StatelessWidget {
+  const IndentedHeaderExample({
+    Key? key,
+  }) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return AppScaffold(
+      title: 'List Example',
+      slivers: [
+        _StickyHeaderList(index: 0),
+        _StickyHeaderList(index: 1),
+        _StickyHeaderList(index: 2),
+        _StickyHeaderList(index: 3),
+      ],
+    );
+  }
+}
+
+class _StickyHeaderList extends StatelessWidget {
+  const _StickyHeaderList({
+    Key? key,
+    this.index,
+  }) : super(key: key);
+
+  final int? index;
+
+  @override
+  Widget build(BuildContext context) {
+    return SliverStickyHeader(
+      header: Header(index: index),
+      slivers: [
+        SliverStickyHeader(
+          header: Header(title: "Subheader #1"),
+          slivers: [
+            SliverList(
+              delegate: SliverChildBuilderDelegate(
+                    (context, i) => ListTile(
+                  leading: CircleAvatar(
+                    child: Text('$index'),
+                  ),
+                  title: Text('List tile #$i'),
+                ),
+                childCount: 6,
+              ),
+            ),
+          ],
+        ),
+        SliverStickyHeader(
+          header: Header(title: "Subheader #2"),
+          slivers: [
+            SliverList(
+              delegate: SliverChildBuilderDelegate(
+                    (context, i) => ListTile(
+                  leading: CircleAvatar(
+                    child: Text('$index'),
+                  ),
+                  title: Text('List tile #$i'),
+                ),
+                childCount: 6,
+              ),
+            ),
+          ],
+        ),
+        SliverStickyHeader(
+          header: Header(title: "Subheader #3"),
+          slivers: [
+            SliverList(
+              delegate: SliverChildBuilderDelegate(
+                    (context, i) => ListTile(
+                  leading: CircleAvatar(
+                    child: Text('$index'),
+                  ),
+                  title: Text('List tile #$i'),
+                ),
+                childCount: 6,
+              ),
+            ),
+          ],
+        ),
+      ],
+    );
+  }
+}

example/lib/main.dart

@@ -1,3 +1,5 @@
+import 'package:example/examples/double_list.dart';
+import 'package:example/examples/indented_header.dart';
 import 'package:flutter/material.dart';
 
 import 'examples/animated_header.dart';
@@ -65,6 +67,14 @@ class _Home extends StatelessWidget {
             text: 'Mixing other slivers',
             builder: (_) => const MixSliversExample(),
           ),
+          _Item(
+            text: 'Multiple Slivers List Example',
+            builder: (_) => const DoubleListExample(),
+          ),
+          _Item(
+            text: 'Indented Slivers List Example',
+            builder: (_) => const IndentedHeaderExample(),
+          ),
         ],
       ),
     );