How to set Divider in PopupMenuItem of flutter?

You can do this very easily using the Theme class, using which you can change the icon color, text color and Default PopupMenuDivider color.

Again, you can easily do this on Divider at PopupMenuItem using PopupMenuDivider.

actions: [
      Theme(
        data: Theme.of(context).copyWith(
          dividerTheme: DividerThemeData(
            color: Colors.black,
          ),
          iconTheme: IconThemeData(color: Colors.white),
          textTheme: TextTheme().apply(bodyColor: Colors.white),
        ),
        child: PopupMenuButton<int>(
          color: Colors.indigo,
          //onSelected: (item) => onSelected(context, item),
          itemBuilder: (context) => [
            PopupMenuItem<int>(
              value: 0,
              child: Text('Settings'),
            ),
            PopupMenuDivider(),
            PopupMenuItem<int>(
              value: 1,
              child: Text('Share'),
            ),
            PopupMenuDivider(),
            PopupMenuItem<int>(
              value: 2,
              child: Row(
                children: [
                  Icon(Icons.logout),
                  const SizedBox(width: 8),
                  Text('Sign Out'),
                ],
              ),
            ),
          ],
        ),
      ),
    ],