title: ExtJS 4 - How to avoid grid column value becoming null when column editor is combo-box?
body: <p>I have a column in a grid with editor as combo-box. </p>
  
  <p>When the grid is loaded then all the column values get displayed properly.</p>
  
  <p>The issue is, when user clicks at the column (having combobox as editor) to edit it then the column value becomes null as shown in the attached screenshot.</p>
  
  <p>I understand that the value becomes null as the store of combobox has not been loaded yet.</p>
  
  <p>I can not use autoLoad true due to the heavy amount of data present in the combobox store. Moreover, even if I use autoLoad:true for the store with paging in it, then that too safeguards only those values which are present in the first page and not all.</p>
  
  <p>Thus, how can I maintain the value in grid column when that value is not present in the store of combobox used as editor for the column?</p>
  
  <p>Could anyone guide at this?</p>
  
  <p>PS: I am using ExtJS Ver 4.0.2a</p>
  
  <p><img src="https://i.stack.imgur.com/HYWUG.jpg" alt="enter image description here"></p>