I have a Flex app that sends an image to a servlet which then resizes it and
writes it to the disk. It also updates the database with the image name for
that record. Then that row in the datagrid needs to change to show the new
image uploaded to the server.

Inside the set data() of the itemRenderer, this code seems to sometimes
replace the image with the new one,

outerDocument.myGrid.invalidateList();

But 9 out of 10 times, it doesn't seem to work at all. After uploading, the
image stays at the old one and doesn't get refreshed to be the new one. What am
I doing wrong? Can you point me to some examples. Thank you.

Is set data() being called when you expect it should?

How are you updating the dataProvider?

Tracy

The propertiesXML variable gets populated an XML file using an HTTPService
call. In its RESULT handler, we call the useHttpService(), which uses values
from the XML file.

In turn, in the RESULT handler of the useHttpService(), we set the
dataProvider of the grid, called dgPremiums (code below).

As for the set data(), I'm not sure how to test to see when it's being called
and when it needs to be called. Where should the call to the invalidateList()
be? I've got it both inside the set data() and also in the UPLOAD_COMPLETE_DATA
event handler of the file upload.

I've spent three days on this and am no closer to an answer. Your help is much
appreciated

private function useHttpService():void {
serviceGridReader.cancel();
var dateate = new Date();
this.serviceGridReader.url =
propertiesXML.property.(name=="ViewHandler").value + "?dt=" +
date.toTimeString();
serviceGridReader.resultFormat = "e4x";
serviceGridReader.contentType = "application/xml"; // Must
have this or will get IOError -- servlet generates XML document.
serviceGridReader.method = "POST";
serviceGridReader.addEventListener(ResultEvent.RES ULT,
httpViewHandlerResult);
serviceGridReader.addEventListener(FaultEvent.FAUL T,
httpViewHandlerFault);
serviceGridReader.send();
}

private function httpViewHandlerResult(event:ResultEvent):void {
premiums = XML(event.result);
this.dgPremiums.dataProvider = premiums.premium;
}

private function httpViewHandlerFault(event:FaultEvent):void {
var errorMessage:ErrorMessage = event.message as ErrorMessage;
Alert.show("rootCause: " + errorMessage.rootCause.toString());
}

If you are re-assigning the dataProvider, as you are, then you can be assured
that set data() is being called on all renderers.

This means the problem is "after"that.

Use a trace() statement (in set data()) to write out the value of the property
that contains the image url. make sure it is correct.

Does your image item renderer store the item in an instance variable in set
data(), then call invalidateProperties()?

Then, in commitProperties() are you using that instace var to set the source
of the image?

Tracy

Hi, Tracy. Thank you for your continued help! It's very much appreciated; I've
been stuck for so long on this problem, I saw no light at the end of the
tunnel.

In answer to your questions, here's what the code does and perhaps you can
guide me as to where the invalidateProperties() and the commitProperties() need
to be called:
- The user clicks the Browse button in the row to select an image file.
- Then s/he can click the Upload button. At this point, the file is sent to
the Java servlet, which resizes it and stores it on the server, with the
record's "Premium ID" being its filename. The Premium ID is an alphanumeric
value, such as "ABCD123".
- The server generates a small XML response, which Flex then reads in the
UPLOAD_COMPLETE_DATA handler. This contains the filename, which is stored on
the datagrid.selectedItem.FileName custom variable; this variable isn't part of
the original dataprovider XML.
- In the set data() of the image column, the code checks to see if that value
exists; if so, it does an image.load() with the path + data.FileName. Else it
sets the image's load() to the value from the dataprovider.

After loading the image using data.FileName, the code calls the
outerDocument.datagrid.invalidateList(). I also have a Refresh button that
calls this. On some occasions, if I hit the Refresh button on the row enough
times, it seems to get the new image in. The code also has calls to the
outerDocument.datagrid.invalidateDisplayList() to no avail.

How does the invalidateProperties() and commitProperties() fit into this? May
you have a wonderful evening. Thanks for your help. Once I'm in the office on
Monday, I can use the trace method. By the way, how do you see the trace
statements? Do they come up in Flex Builder when the app is running? Sorry for
the newbie questions.

I'm eager to learn Flex because I see the potential for it for everybody who
builds for the Web. For me, these are growing pains

Hi. I've tried using the invalidateProperties() and commitProperties() in the
itemRenderer, but it's not working correctly. Here's the code for the column,

<mx:AdvancedDataGridColumn id="imageCol" headerText="Image Column"
wordWrap="true">
<mx:itemRenderer>
<mx:Component>
<mx:VBox>
<mx:Script>
<![CDATA[
import mx.controls.Text;
import mx.events.FlexEvent;

private var fileName:String = "";
private var loaded:Boolean = false;

override public function set data(value:Object):void {
super.data = value;

invalidateProperties();
dispatchEvent(new FlexEvent(FlexEvent.DATA_CHANGE));

if (data.FileName != undefined && data.FileName != null
&& data.FileName != ""){
loaded = true;
fileName = data.FileName;
}
else if (getFilename(data) != null) {
loaded = true;
fileName = getFilename(data);
}
}

public function getFilename(item:Object):String {
if (item.image == undefined || item.image.filename == undefined) {
return null;
}
else {
return item.image.filename;
}
}

// Implement the commitProperties() method.
override protected function commitProperties():void {
super.commitProperties();

var path:String = "http://myserver.com/servlet/fpauto/uploads/";

photoLoad.load(path + fileName);
}

override protected function createChildren() : void {
super.createChildren();

if (loaded) {
photoLoad.visible = true;
photoBox.removeAllChildren();
}
else {
var text:Text = new Text();
text.text = "";
text.text = "No Photo Found";

photoBox.removeAllChildren();
photoBox.addChild(text);
photoLoad.visible = false;
}
}
]]>
</mx:Script>
<mx:Image id="photoLoad" visible="false" autoLoad="false" />
<mx:HBox id="photoBox">
</mx:HBox></mx:VBox>
</mx:Component>
</mx:itemRenderer>
</mx:AdvancedDataGridColumn>

"curious_Lee" <webforumsuser@macromedia.com> wrote in message
news:ge4g9u$f3n$1@forums.macromedia.com...
> Hi. I've tried using the invalidateProperties() and commitProperties() in
> the
> itemRenderer, but it's not working correctly. Here's the code for the
> column,

instead of using photoLoad.load(), have you considered setting
photoLoad.source = path+fileName?

I tried that, but get no images displaying. Not sure why.

"curious_Lee" <webforumsuser@macromedia.com> wrote in message
news:ge4je0$j68$1@forums.macromedia.com...
>I tried that, but get no images displaying. Not sure why.

I'd put a breakpoint on the closing brace of commitProperties() and inspect
the properties of photoLoad. Might give you some insight.

Finally found a solution:
- Changed the Java servlet to concatenate the time in milliseconds to the
filename, ensuring it will be unique. Earlier, the filename for that record was
the same as its ID; this increased the likelihood of caching.
- Modified the Flex app to refresh the dataProvider for the grid with each
upload. Based on a tip by a blogger
(http://joelhooks.com/2008/02/07/flex...g-when-the-dat
aprovider-is-updated/), I'm able to put the user back at the same record again
after the refresh.