title: Telerik radgridview merge/group
body: <p>I'm working on an small C# (WPF + SQLite) application where I'm implementing <code>RadGridView</code> from Telerik.
  I want to merge all columns where is the same ID like in the table. Right now my data looks like this (this is my view).</p>
  <pre><code>╔════╤═══════╤══════════╤══════╗
  ║ id │ ime   │ surname  │ year ║
  ╠════╪═══════╪══════════╪══════╣
  ║ 1  │ Name1 │ Surname1 │ 1994 ║
  ╟────┼───────┼──────────┼──────╢
  ║ 1  │ Name1 │ Surname1 │ 1995 ║
  ╟────┼───────┼──────────┼──────╢
  ║ 2  │ Name2 │ Surname2 │ 1996 ║
  ╟────┼───────┼──────────┼──────╢
  ║ 3  │ Name3 │ Surname3 │ 1996 ║
  ╚════╧═══════╧══════════╧══════╝
  </code></pre>
  <p>And this is what I want to achive in my RadGridView.</p>
  <pre><code>╔════╤═══════╤══════════╤═══════╗
  ║ id │ ime   │ surname  │ year  ║
  ╠════╪═══════╪══════════╪═══════╣
  ║ 1  │ Name1 │ Surname1 │ 1994  ║
  ║    │       │          │ 1995  ║
  ╟────┼───────┼──────────┼───────╢
  ║ 2  │ Name2 │ Surname2 │ 1996  ║
  ╟────┼───────┼──────────┼───────╢
  ║ 3  │ Name3 │ Surname3 │ 1996  ║
  ╚════╧═══════╧══════════╧═══════╝
  </code></pre>
  <p>The solution and the problem is merge option who radgridview has. But it mergers all data who are the same value. And it looks okay but the functionality is bad.</p>
  <p>It does what I sad but when I try to click the merged cell after double click it does this. (In this example I clicked surname1 cell)</p>
  <pre><code>╔════╤═══════╤══════════╤═══════╗
  ║ id │ ime   │ surname  │ year  ║
  ╠════╪═══════╪══════════╪═══════╣
  ║ 1  │ Name1 │ Surname1 │ 1994  ║
  ╟────────────┼──────────┤ 1995  ║
  ║            │ Surname1 │       ║
  ╟────────────┼──────────┼───────╢
  ║ 2  │ Name2 │ Surname2 │ 1996  ║
  ╟────┼───────┼──────────┼───────╢
  ║ 3  │ Name3 │ Surname3 │ 1996  ║
  ╚════╧═══════╧══════════╧═══════╝
  </code></pre>
  <p><a href="https://i.stack.imgur.com/CnaIn.png" rel="noreferrer"><img src="https://i.stack.imgur.com/CnaIn.png" alt="This is my radgridview, the red marked is where i double clicked, and the green cells are one who I want to not to merge + after clicking that row I want it to be selected." /></a></p>
  <p>This is my radgridview, the red marked is where i double clicked, and the green cells are one who I want to not to merge + after clicking that row I want it to be selected.</p>