Datagrid checkbox headerrenderer check off problem

Question

I have a datagrid where one column has select option like what we have in mail inboxes. User can select one or many row items to perform any actions by selecting the checkbox. It has also one select all option which is shown in the header renderer of that particular column. If user clicks on that all checkboxes gets selected.
I have done that but the problem is that whenever i am performing any action by selecting all(header checkbox) and as a result the datagrid sometimes sets visible off or switches to some other mxml component from the component which is holding the datagrid and after coming back from that scenario again to the datagrid, its seen that the checkbox is still checked ... i want that checkbox to set to non-checked.
help me.

Answer 1

Hi subhajit nag,
Say the below is your mxml component in viewStack...
<your component>
<mx:Script>
<![CDATA[
[Bindable]private var headerChecked:Boolean = false;
private function onShow():void
     headerChecked = false;
]]>
</mx:Script>
</your component>
<mx:DataGrid x="35" y="10" id="mydg">
        <mx:columns>        
            <mx:DataGridColumn editable="true" sortable="false">
             <mx:headerRenderer>
              <mx:Component>
                        <mx:CheckBox selected="{outerDocument.headerChecked}" click="checkUnCheckCheckBoxes()">
                         <mx:Script>
                  <![CDATA[
                   import mx.collections.ArrayCollection;
               private function checkUnCheckCheckBoxes():void
                  // You can handle your logic what you want to do when header check box is clicked....   
                  ]]>
              </mx:Script>
                        </mx:CheckBox>
                    </mx:Component>
             </mx:headerRenderer>
                <mx:itemRenderer>                
                    <mx:Component>
                        <mx:CheckBox selected="{data.isSelected}" click="{data.recselected = !data.recselected}"/>
                    </mx:Component>
                </mx:itemRenderer>
            </mx:DataGridColumn>
            <mx:DataGridColumn headerText="Column 1" dataField="firstName"/>
            <mx:DataGridColumn headerText="Column 2" dataField="lastName"/>           
        </mx:columns>
    </mx:DataGrid>
So you just need to change the value of the headerChecked  bindable variable to false..in show event for your first scenario...and your header check box is automatically unselected because this check box is binded to a bindable variable to which you are setting to false...
For your second scenario....you can use the same changing the headerChecked value to false...
You need to set this varibale to false in your second scenario where you know that your Header Render datagrid is making it visible after you made it unvisible...
say you have clicked header check box and you made this datagrid invisible and this header checkbox datagrid will be visible once again when you click toggle button so set the value to false in the toggle button click function....
private function toggleButtonClickHandler():void
     headerChecked = false;
     yourHeaderChkDataGrid.visible = true;
     yourAnotherDG.visible = false;
Hope this is clear for you now...Try this and let me know...
Thanks,
Bhasker Chari