title: Qt Get char from hex
body: <p>i have a QString with a hex code of one Char in it. I want to get the Char. 
  I tried <a href="http://qt-project.org/doc/qt-5.0/qtcore/qbytearray.html#fromHex" rel="nofollow">http://qt-project.org/doc/qt-5.0/qtcore/qbytearray.html#fromHex</a> but fromHex needs a "const QByteArray". So </p>
  
  <pre><code>QByteArray value = QByteArray::fromHex( "70" ) ;
  </code></pre>
  
  <p>works, but</p>
  
  <pre><code>QByteArray value = QByteArray::fromHex( var ) ; //QString var = "70"
  </code></pre>
  
  <p>doesn't.
  Is there any possibility to get the Char from the Hex-Code?</p>
  
  <p>Thanks in advance!</p>