David PHAM-VAN

Fix dart warning

@@ -144,7 +144,7 @@ class TableOfContent extends StatelessWidget { @@ -144,7 +144,7 @@ class TableOfContent extends StatelessWidget {
144 child: Row( 144 child: Row(
145 children: [ 145 children: [
146 SizedBox(width: 10.0 * l), 146 SizedBox(width: 10.0 * l),
147 - Text('${c.title}'), 147 + Text(c.title!),
148 SizedBox(width: 8), 148 SizedBox(width: 8),
149 Expanded( 149 Expanded(
150 child: Divider( 150 child: Divider(