title: Flex 4.6: could not resolve <mx:DataGrid> to a component implementation
body: <p>I'm very new at this. Building a "Flex Application" mobile app for Android devices.
  Running the latest Flex/FlashBuilder (4.6). </p>
  
  <p>Looking at Project Properties:
  Builders: Flex &amp; AIR application Builder
  Flex Compiler: "Use default SDK (currently "Flex 4.6.0")
  In my design view I definitely don't see a MX DataGrid control. I added the control to my app by pasting code from the last example on this page: 
  <a href="http://help.adobe.com/en_US/flex/using/WS2db454920e96a9e51e63e3d11c0bf66ce9-7ff2.html" rel="nofollow">http://help.adobe.com/en_US/flex/using/WS2db454920e96a9e51e63e3d11c0bf66ce9-7ff2.html</a></p>
  
  <p>When I compile I get this error: <em>"could not resolve  to a component implementation"</em>. Here is my code:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;!-- dpcontrols/DataGridPassData.mxml --&gt;
  &lt;s:View xmlns:fx="http://ns.adobe.com/mxml/2009"
                      xmlns:s="library://ns.adobe.com/flex/spark"
                      xmlns:mx="library://ns.adobe.com/flex/mx" 
                      title="Jobs List"&gt;
            &lt;fx:Script&gt;
                      &lt;![CDATA[
                                import mx.collections.*;
                                private var DGArray:Array = [
                                          {Lease:'Bagby Heirs', Well:'1', Location:'Quitman', Customer:'Fair Oil Company', ScheduleDate:'2/23/2012', ServiceDate:'5/16/2012'},
                                          {Lease:'ITU', Well:'301', Location:'Ingram Trinity', Customer:'Southwest Operating, Inc.', ScheduleDate:'3/19/2012', ServiceDate:'4/25/2012'},
                                          {Lease:'ITU', Well:'81', Location:'ITU', Customer:'Southwest Operating, Inc.', ScheduleDate:'3/19/2012', ServiceDate:'4/25/2012'},
                                          {Lease:'Tolliver A', Well:'5', Location:'Turner Town', Customer:'SEDI', ScheduleDate:'4/16/2012', ServiceDate:'5/11/2012'},
                                          {Lease:'W R Cady', Well:'1', Location:'Coffield', Customer:'Green River Resource', ScheduleDate:'5/9/2012', ServiceDate:'4/10/2012'},
                                          {Lease:'Royal National Bar', Well:'2', Location:'Coffield', Customer:'Green River Resource', ScheduleDate:'5/9/2012', ServiceDate:'4/10/2012'},
                                          {Lease:'Pan American L', Well:'1', Location:'Chandler', Customer:'East Texas Oil &amp; Gas', ScheduleDate:'5/14/2012', ServiceDate:'6/8/2012'},
                                          {Lease:'Paluxy B Sand', Well:'5', Location:'West Tyler', Customer:'Culver &amp; Cain', ScheduleDate:'6/1/2012', ServiceDate:'5/25/2012'},
                                          {Lease:'Wh Pittman Hei', Well:'2', Location:'Quitman', Customer:'Southwest Operating, Inc.', ScheduleDate:'7/10/2012', ServiceDate:'6/18/2012'},
                                          {Lease:'Vivian Pruitt', Well:'1', Location:'Crow - Hwy 80M', Customer:'Buffco Productions, Inc.', ScheduleDate:'8/7/2012', ServiceDate:'8/29/2012'}
                                ];
  
                                [Bindable]
                                public var initDG:ArrayList;
  
                                //Initialize initDG ArrayList variable from the Array.
                                //If you use this technique to process an HTTPService,
                                //WebService, or RemoteObject result, use an ArrayCollection
                                //rather than an ArrayList.
                                public function initData():void {
                                          initDG=new ArrayList(DGArray);
                                }
                      ]]&gt;
            &lt;/fx:Script&gt;
            &lt;!--s:states&gt;
            &lt;s:State name="loginState"/&gt;
            &lt;s:State name="State1"/&gt;
            &lt;/s:states--&gt;
  
            &lt;fx:Declarations&gt;
  
                      &lt;!-- Place non-visual elements (e.g., services, value objects) here --&gt;
                        &lt;fx:Component className="AlertMsgDay"&gt;
                                &lt;s:SkinnablePopUpContainer x="70" y="300"&gt;
                                          &lt;s:TitleWindow title="Filtering" close="close()"&gt;
                                                    &lt;s:VGroup horizontalAlign="center" paddingTop="8" paddingBottom="8" paddingLeft="8" paddingRight="8" gap="5" width="100%"&gt;
                                                              &lt;s:Label text="This button will filter jobs to show only TODAY."/&gt;
                                                              &lt;s:Button label="OK" click="close()"/&gt;
                                                    &lt;/s:VGroup&gt;
                                          &lt;/s:TitleWindow&gt;
                                &lt;/s:SkinnablePopUpContainer&gt;
                      &lt;/fx:Component&gt;
  
                      &lt;fx:Component className="AlertMsgWeek"&gt;
                                &lt;s:SkinnablePopUpContainer x="70" y="300"&gt;
                                          &lt;s:TitleWindow title="Filtering" close="close()"&gt;
                                                    &lt;s:VGroup horizontalAlign="center" paddingTop="8" paddingBottom="8" paddingLeft="8" paddingRight="8" gap="5" width="100%"&gt;
                                                              &lt;s:Label text="This button will filter jobs to show only THIS WEEK."/&gt;
                                                              &lt;s:Button label="OK" click="close()"/&gt;
                                                    &lt;/s:VGroup&gt;
                                          &lt;/s:TitleWindow&gt;
                                &lt;/s:SkinnablePopUpContainer&gt;
                      &lt;/fx:Component&gt;
  
            &lt;/fx:Declarations&gt;
  
            &lt;s:BorderContainer x="10"  y="111" borderColor="#808080" cornerRadius="5" borderWeight="2" width="98%" height="369"&gt;
                      &lt;s:Scroller width="100%" height="363" verticalScrollPolicy="on"&gt;
                                &lt;s:Group width="100%" height="100%"&gt;
  
  
                                          &lt;mx:DataGrid id="myGrid" width="900" height="350" dataProvider="{initDG}" &gt;  &lt;&lt;&lt;&lt; THE ERROR IS HERE
                                                    &lt;mx:columns&gt;
                                                              &lt;mx:DataGridColumn dataField="Lease" /&gt;
                                                              &lt;mx:DataGridColumn dataField="Well" /&gt;
                                                              &lt;mx:DataGridColumn dataField="Location" /&gt;
                                                              &lt;mx:DataGridColumn dataField="Customer" /&gt;
                                                              &lt;mx:DataGridColumn dataField="ScheduleDate" headerText="Schedule Date" /&gt;
                                                              &lt;mx:DataGridColumn dataField="ServiceDate" headerText="Service Date" /&gt;
                                                    &lt;/mx:columns&gt;
                                          &lt;/mx:DataGrid&gt;
  
                                &lt;/s:Group&gt;
                      &lt;/s:Scroller&gt;
            &lt;/s:BorderContainer&gt;
  
            &lt;s:Label x="10" y="10" width="96" height="53" fontSize="24" text="Sort by:"
                                 verticalAlign="middle"/&gt;
            &lt;s:Button id="btn_show_today" x="104" y="11" width="105" height="53" label="Today"
                                  fontSize="13" fontWeight="bold" click="(new AlertMsgDay()).open(this, false);"/&gt;
            &lt;s:Button id="btn_show_week" x="216" y="11" width="105" height="53" label="Week"
                                  fontSize="13" fontWeight="bold" click="(new AlertMsgWeek()).open(this, false);"/&gt;
            &lt;s:Button x="348" y="10" width="184" height="53" label="Edit this Job" fontSize="18" click="navigator.pushView(views.JobFormView);"/&gt;
  &lt;/s:View&gt;
  </code></pre>