Hello Belial_X,
you have add one extra line of code to get the required out put . actually selecting an item programmatically does not automatically change the focus to the ListView control. For this reason, you will typically want to call the Focus method when selecting an item.
int next = Convert.ToInt32(listView1.FocusedItem.Index) + 1;
this.listView1.Focus();
this.listView1.Items[next].Selected = true;
Check the reference :
Select an Item in the Windows Forms ListView Control
Don't forget that there may be
ArgumentOutOfRangeException
error comes as you directly add the index by 1 . so, try to modify the code as per requirement .
thanks