title: DART lang, working with list of Map, how?
body: <p>I'e a sales order of many lines, want to handle each line as a Map of (number, Item code, Qty), and need to have all these maps in list, so that orderlines[0] is the Map of the first order line.</p>
  
  <p>If I've 3 lines, then the below worked very well.</p>
  
  <p>But what if I do not know the number of lines, and it depend on the user, then how can define it!</p>
  
  
  
  <pre class="lang-dart prettyprint-override"><code>  var orderLines = [{ 'number'  : '',
                    'Item' : '',
                    'Qty'  : ''
                   },
                   { 'number'  : '',
                    'Item' : '',
                    'Qty'  : ''
                   },
                   { 'number'  : '',
                    'Item' : '',
                    'Qty'  : ''
                   }
                 ];
  </code></pre>
  
  <p>I need to define the "orderLines" so I can get it filled by the data in the below code:</p>
  
  <pre class="lang-dart prettyprint-override"><code>   for(int i=0;i&lt;=number_of_lines;i++){
         orderLines[i]['number']=element.childNodes[i].childNodes[0].value;
         orderLines[i]['number']=element.childNodes[i].childNodes[1].value;
         orderLines[i]['Qty']=element.childNodes[i].childNodes[2].value;  
   }
  </code></pre>