I wish I could claim credit, but I'm not the FlexExamples guy. I was thinking of my post here: http://blogs.adobe.com/aharui/2008/02/checkbox_selection_in_datagrid.html
From: [email protected] [mailto:[email protected]] On Behalf Of stldvd Sent: Tuesday, January 06, 2009 5:39 PM To: [email protected] Subject: [flexcoders] Re: Validating Checkboxes in an item renderer I also tried adding this to the arrColl_collectionChange function: if(list.selectedIndex == -1) { Alert.show("No items are selected!"); } But the only time it fires is when the app first loads, presumably because the list isn't yet populated. If I uncheck all the checkboxes, it doesn't show. The event in question is the change event of the checkbox, so it seems to me this ought to work. No? I did get it to work by modifying as follows: if(!tArr.length) { Alert.show("No items are selected!"); } --- In [email protected]<mailto:flexcoders%40yahoogroups.com>, "stldvd" <stl...@...> wrote: > > Hi Alex, > > I've been studying your code at > http://blog.flexexamples.com/2008/01/27/using-a-checkbox-control-as-a-list-item-renderer-in-flex/ > > You use the filter method on the underlying array (source) for the > arrayCollection datasource of the list. The signature of your function is: > > private function selectedOnly(item:ListItemValueObject, idx:uint, > arr:Array):Boolean { > return item.isSelected; > } > > The filter method, according to the Flex docs, 'executes a test > function on each item in the array and constructs a new array for all > items that return true for the specified function.' That I understand, > and I can see that you're being returned an array, tArr. But how are > you able to call a function with that signature and know that all > three parameters are going to be passed in? I tried adding a fourth > parameter - , porky:String - and it broke. How does this method know > that idx:uint is OK, but porky:String isn't? > > > > --- In [email protected]<mailto:flexcoders%40yahoogroups.com>, Alex > Harui <aharui@> wrote: > > > > You could use a derivative of the example on my blog and then just > test if selectedIndex != -1 > > > > From: [email protected]<mailto:flexcoders%40yahoogroups.com> > > [mailto:[email protected]<mailto:flexcoders%40yahoogroups.com>] > On Behalf Of stldvd > > Sent: Tuesday, January 06, 2009 1:47 PM > > To: [email protected]<mailto:flexcoders%40yahoogroups.com> > > Subject: [flexcoders] Validating Checkboxes in an item renderer > > > > > > Hi All, > > > > I've got a checkbox in an item renderer. I need to know that at least > > one checkbox has been selected in order for the data to be considered > > valid and the 'save' function to go through. But I'm not sure how to > > iterate through the checkboxes, since in the code there's only one: > > > > <mx:VBox> > > <mx:List id="myList" dataProvider="{_dp}" > > > <mx:itemRenderer> > > <mx:Component> > > <mx:HBox horizontalScrollPolicy="off"> > > <mx:CheckBox selected="false" /> > > <mx:Label text="Sample" textAlign="right" width="150" /> > > </mx:HBox> > > </mx:Component> > > </mx:itemRenderer> > > </mx:List> > > </mx:VBox> > > > > Any help appreciated. > > > > -- David > > >
