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Chained ComboBox Flex Sdk 3.5 issue finally got workaround

Hi folks,

Few days earlier I also switched from flex sdk 3.2 to flex sdk 3.5 where in sdk 3.2 every thing was running perfect including chained combobox, but while switching to flex sdk 3.5 I have noticed that in combobox a bug reproduced when using chained combobox and spoils my whole application. I also came to flex forum blog where it was suggested to switch to flex sdk 3.6 but I don't want to switch sdk 3.6 as it was nightly build and I want to prefer release one. So I had decided to go in the code to see why this happens. While playing with code I have seen a shared dataprovider is used for combo box and the dropdown.

So, I realize that there is some issue while re-assigning the dataprovider to the dropdown and only need to correct this. But unfortunately that function where the dropdown dataprovider is set is private. So I decided to manully set the shared dataprovider to the dropdown whenever the comboBox dataprovider is changed by extending combobox and overriding function set dataProvider(value:Object):void . and voila my issue has been relsolved.

But later on I had realized that setting dropdown's dataprovider in combobox dataprovider setter leads to again further unseen issue of dropdown width and rowheight which reproced in my application randomly, which I had not realized earlier and leads to again drill down the ComboBox sdk code.

There I found a mx_internal function hasDropdown():Boolean which is used to determine whether comboBox dropdown is created or not. So I have to decided to override this mx_internal function and return false whenever the dataprovider of comboBox is changed.

By doing this, all issue has been gone as they were never before and works perfectly.
My demo is view source enabled, you can view the source code by right clicking on the application.

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Custom filterable column for DataGrid Flex 3 with Sorting enabled

This post is deeply inspired from the post at Cookbook recipe for filtering data grid. This post is about to enable the sorting on the dataGrid column which I found missing in the recipe.

Code is not very well documented, but is very easy to understand and use.

Please feel free, if you requires any help.

View Source is enable at right click on demo.

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a different kind of popup button

Have you ever had a requirement that the whole clickable area of your popupbutton should show the dropdown instead of just the small button on the right? This control does exactly the same.It derives heavily from the concept of the normal popupbutton and combo box in flex but with the slight twist to the end functionality.Have a look.

Compiling flexlib from source

Flexlib is an excellent component library which I have used extensively , especially the MDI framework. Recently we encountered an issue in flexlib swc which was actually a bug. Hoping that it could have been fixed in the latest builds, i set about to compile it. Although the site itself has almost all the requisite stuff but somehow all the steps are not there at a particular place so maybe this helps somebody out. But please note they are windows specific. you would need

1. an anonymous checkout of the code first using svn as described here.
2. apache ant(mine was 1.7.1) as the build tool. (it helps if you add the bin folder in your installation to the path variable on your machine)

Go to the build folder under flexlib on a command prompt. You will notice a file called build.xml and another build.win.properties. They need to modified a bit according to your settings - For flex 3 - In build.win.properties add these new variables(make sure to change the values to your flex install directory). I added it at line number 15, but its up to you. flexsdk.bin.dir = C:/Program Files/Adobe/Flex Builder 3/sdks/3.2.0/bin flexsdk.lib.dir = C:/Program Files/Adobe/Flex Builder 3/sdks/3.2.0/frameworks/libs flexsdk.locale = en_US flexsdk.locale.dir = C:/Program Files/Adobe/Flex Builder 3/sdks/3.2.0/frameworks/locale/{locale} change these variables to use the new variables asdoc.exe = ${flexsdk.bin.dir}/asdoc.exe compc.exe = ${flexsdk.bin.dir}/compc.exe mxmlc.exe = ${flexsdk.bin.dir}/mxmlc.exe In build.xml uncomment this line (32) <

property file="./build/build.win.properties" / >

and comment this one(33)

<

property file="./build/build.mac.properties" />

on line (24) update the basedir attribute to your flexlib directory(an absolute path is good enough)

<

project name="flexlib" basedir="C:\Project\GoogleCode\flexlib" default="lib" >

Going to line 118,you would need to uncomment this line

<

arg line="-el '${flexsdk.lib.dir}/player'" /> and change it, so that I could compile flexlib for flash player 10. <arg line="-el '${flexsdk.lib.dir}/player/10'" />

Thats it, now on command prompt go the flexlib/build directory and run ant(which is as simple as ant + enter key,if you followed the first part of the post correctly) if all goes good you should see a flexlib.swc in the bin flexlib/bin folder.

Error border skin in Textinput

A flex Textinput control uses the errorcolor property to change the border color when a validator associated with the component fails to validate the textinput.

Interestingly this color does not appear when the same textinput is using a flash based focus skin.The problem is that the focus skin tends to hide the error color around so after a bit of investigation and there is no style which would let us specify a border skin for the error state.So we found the solution by subclassing textinput and defining another style called errorskin(which is just another border skin that you would want to use for showing validation errors,preferably in a red shade).

Check out the working sample(with view source).

LCDS to BlazeDS porting

Introduction

This document is designed to explain key features of BlazeDS and LCDS. Main purpose of this document is to provide a solution to implement Data Management Services with BlazeDS. Data Management Service is currently supported by LCDS only.

Introduction to Live Cycle Data Service

Live Cycle Data Service (LCDS) is a high-performance, scalable, flexible j2ee server based framework that streamlines the development of RIAs using Adobe software and the Adobe AIR runtime. Lifecycle Data Services abstracts the complexity required to create server push–based applications and supports a rich set of features to create real-time and near-real-time solutions. Live Cycle Data Services API, simplifies data management problems such as tracking changes, synchronization, paging, and conflict resolution. Flex and AIR applications use Flex components to communicate with the LiveCycle Data Services server, including the RemoteObject, HTTPService, WebService, Producer, Consumer, and DataService components. The HTTPService, WebService, Producer, and Consumer components are part of the Flex Software Development Kit (SDK). A LiveCycle Data Services application consists of two parts: a client-side application in Flex or AIR and a server-side J2EE web application.

Key features

Some of the real-time feature and capabilities of Live Cycle Data Service are:

• Provides the interactivity required for applications to present real-time data to clients. It enables the client to maintain a persistent connection to the server. Use the Action Message Format (AMF) channel, which enables faster data transmission.
• Provides an enterprise-class, real-time platform that can push data from multiple sources, including changes from other users, to the Flash and Adobe AIR runtimes. Support Data Management service which is discussed latter in this document.
• Provides PDF technology with flex
• Provides Service Adapter which is responsible for updating the persistent data store on the server in a manner appropriate to the specific data store type
• Use message-based framework to send data back and forth between the client and server.
• Facilitates the paging of large data sets, enabling developers to focus on core application business logic instead of worrying about basic data management infrastructure.
• Enables data to automatically be pushed to the client application without polling