A couple of weekends ago, I did a presentation for The Chennai Cold Fusion User Group (CCFUG Homepage). Am posting the ppt here. The presentation covered the basics - intro to RIAs, intro to Adobe Flex, a couple of examples and a little bit about Adobe AIR. Check it out… if you have nothing else to do … The audience were cold fusion developers who were new to Adobe Flex and Adoe AIR. I touched the basics and then walked them through some code examples of Flex and Air.

Check out some snaps from the event and check out this post by Akbar after the event. You may also want to check out the CCFUG homepage at http://www.cfugind.com.

Lately I have been getting a lot of mails about using CForm. So, I kind of wrapped up the whole thing into a SWC and here it is. So all you need to do is download this and add this to the Lib of your project. For the source code, you can still check it out of SVN. But, to just use the CForm, you really do not need the source-code, you can just use this swc component. Click here to download the component.

CForm is all about creating data entry screens. This component allows developers to create standardized forms/CRUD screens in their applications. The CForm component is a Data Entry component that can be very useful if -

1. you are building business applications with many data entry/view screens
2. you are working with a lot of developers. each handling separate screens/modules
3. you wish all your screens to have the standard look & feel across the application
4. you wish to avoid different developers/designers designing their own UI/UX paradigms for their specific screens

Let me try to explain this in a very simplified manner. CForm reads XML file to create user entry forms. To implement CForm, the following steps are involved.

• Developer creates XML file for each screen. The XML will contain the list of fields, controls to be used etc.
• CForm is called in an MXML.
• Now, the developer can use many of CForm’s exposed methods to access/manipulate data in the CForm.

The Demo walks you through a few use cases of how CForm can be used in real world. There are clear instructions on each example in the demo. For a detailed documentation on the XML part of this component, check out here and for the AS and MXML angle check out below. The source code will also be made available shortly in a 2 or 3 weeks. As of now, if you need the source code you will have to check it out from the SVN repository at http://flexedtoolkit.googlecode.com/. If you like this component and would be willing to extend a helping hand, send me a mail .

If you have any questions/suggestions after viewing the demo, leave a comment on this page!!

**Update: Compiled SWC now available for download.

[ SWC | Demo | XML Documentation | Source of Example ]

CForm Properties

CForm Methods

Events

Internals

CForm internally uses extended versions of the standard flex widgets. The extended widgets implements a common single interface - CFormItemRenderer.The extended widgets have some preset properties like height, width, stylename etc. These constant values are picked from DefaultConfig class.

Using CForm

MXML code

<flexed:CForm id=”cfrm”widgetsFile=”controls.xml” cFormValidation=”validateForm”verticalCenter=”0″ verticalScrollPolicy=”auto”
horizontalCenter=”0″ horizontalScrollPolicy=”off”
width=”100%” height=”100%”/>

AS Code

To set xml path and load CForm

str = “examples/cform/xmls/controls.xml”;
cfrm.widgetsFile = str;cfrm.init();

To get data from CForm

obj = cfrm.getData(); // to get only modified values
obj = cfrm.getData(false); // to get all values

To reset CForm

cfrm.resetCForm();

To set data to CForm

var oDataToSet:Object = new Object();
oDataToSet.fname = “udayms”;
oDataToSet.age = 27;
oDataToSet.gender = “male”;
cfrm.setData(oDataToSet);

To access one field in the CForm and access properties of the widget

cfrm.getWidget(“fname”).getUIComponent().addEventListener();

To create CForm on the fly using dynamic XML

cfrm.createCFormFromXML(new XML());

To Validate CForm using custom validation

// custom validation function
private function validateForm(id:String,
value:Object, values:Object):ValidationResult{
var result:ValidationResult = new ValidationResult(false);
if(id == “txtCoName”){
if(value == “” || value == null) result = new ValidationResult(true,null,“”,
“You HAVE to enter a company name!”);
}
return result; }
// do this to actually validate the
// CForm. Internally it
// will use validateForm() method.
cfrm.validateCForm();

I guess this covers most of the usecases. Anyway check out the demo. That should give pretty much a clear idea of what is possible with this component.

So, after a couple of months of hibernation, am slowly trying to catch up on my blogging activities …. Here’s wishing you all a very Happy and Prosperous 2008. Looking forward to another year of pleasant surprises from Adobe, Apple, M$, Google, Yahoo and all the other folks who actually make technology work for the rest of us!!!

I have finally managed to wrap up work on a component that has been pending for a long time. A component for developers to create data entry/crud forms easily. Check out my separate post on this!!!

So, once again… Cheers! And let’s hope this year is filled with less destruction and more peace than last year…

I guess this is already old news by now. But, I just recently happened to check it out. I came to know about such an application when my Manager suggested it. After trying it out, I have one word - AWESOME!!!!

Ok. What I am talking about here is a full fledged online document application (Yeah! Just like Writely, Google Docs) developed in FLEX!!!! I was amazed at not only how feature rich the app was. I was stumbled totally because many of the stuff they have achieved. They have done stuff which I never thought was possible using Flex.

For me, Buzzword definitely takes Flex to the next level. It has been developed by the folks at Virtual Ubiquity. It says on their site -

Buzzword, the first real word processor for the web, is a breakthrough in collaborative authoring for documents that matter. Many online pundits agree with us.

And Guess what? Adobe is acquiring them. You can register and try it out yourself here. Check out the screenshots here. Click on thm to see a larger view.

I am releasing the v1.2 of CGrid. It’s been in drafts for a long while now.This time, a few more basic niceties have been added to the CGrid.

1. Export to Excel (Copy selected rows or entire grid to clipboard and paste in excel)
2. User can select columns to view and width of the columns etc. This setting for each grid in the application is remembered across sessions.(For this to work properly, you will have to ensure that you always specify a distinct ID for for each grid in your application.) This feature is very useful, if you are fetching a lot of columns to display but are not sure whether all the users would be interested in all the columns. Now, the user can choose to see columns of his/her choice and that choice is remembered across sessions.
3. Fixed the sorting logic in the column sort.
4. The CGrid can now take in custom itemRenderer from the caller.

Check it out… For more details about what CGrid is all about, check out this post.

It’s been a long time since I updated the grid component. Hey, for that matter… It’s been a log while since I last posted here. Been quiet a bit busy lately. Anyway, am almost back. This month is also going to be a bit hectic. But, I hope to post regularly from September onwards.

Note: Thanks to all who downloaded CGrid v1.0 and used them in their projects. It really feels nice to see that the component has served some good purpose. The CGrid component is individually responsible for keeping my blog alive and  bringing in readers even though I haven’t posted anything new for the last couple of months. So, this component is kind of the ‘old man’ of this blog. Anyway, Lemme thank all visitors for checking it out. Keep downloading. Keep leaving comments ….

[ Demo | Source | Sample Printout ]

WANTED: Developers who can contribute to this open source initiative

I have created a google project to put in some of the stuff that we have been working on and releasing through this blog. Some of the stuff that you can already download from Flexedtoolkit are -

1. Autorefresher
2. Client Idle Timeout
3. Custom Alerts
4. Custom Grid

I am working on a small component - CForms. The idea is to have a generic UI rendering engine that will create forms from an XML file. This is particularly useful in serious business applications where you have a lot of user entry screens. So, if the developer needs to have a screen, they just include something like -

<widgets:CForm controlsFile=”controls.xml” id=”VLAN”/>

Everything else - Styles, layout, look and feel etc. will be handled by the CForm component as per instructions in the abc.xml… Getting a picture?

We initially did this as part of my project requirements at work. And it was a life-saver. Now, I would like to extend it beyond what it is today. I want to make it more generic and feature rich so that others can leverage on it.

The project homepage is http://code.google.com/p/flexedtoolkit. If you are interested in joining the project, do leave a comment. Really hope some of you folks would find time to work on this.

Readers: I will be in Bangalore till the 25th of this month. Would love to meet some of you folks… If you have time, do leave a comment and maybe we can catch up for tea or something…..

If you have been working on applications which serve highly dynamic data on the screen, you are most likely to have had to rely on the “polling” mechanism to get updated data from the back-end. We had similar requirement in our project and we created a tiny component using Flex’s Timer Class to fire a specific method at set frequencies.

And as usual, we didn’t to go around writing code all across the application to do this. The component we created can take in a function as an attribute. This function could be anything. It could be one that fires an SQL query and updates an ArrayCollection, or it could be one that sends out a Feed request or whatever! It’s pretty easy to use the AutoRefresher. All you have to do is add the AutoRefresher to your view -

<flexed:AutoRefresher id="exampleAutoRefresh" delay="5000" refreshFunction="FunctionToBeFiredPeriodically" />

The view then, refreshes every x milliseconds specified for delay. The default is 15000 milliseconds or 15 seconds. In the init method of your view, before starting the autorefresher, set the owner of the refresher to the parent like this-

exampleAutoRefresh.owner = this;
exampleAutoRefresh.start();


Setting the owner is to make sure that our refresher stops and starts based on the views visibility. In most cases, Polling mechanism ends up being really costly on the back-end. Especially if you are dealing with multi-tiered architecture and trying to talk to a web server, database server etc over the network. And its very much possible, that multiple views in your application might be required to autorefresh periodically. If you are polling in all the screens whether they are required or not, you are most likely to end up crashing the back-end infrastructure. In order to address this problem and minimize the load on the back-end, we built in a mechanism into the refresher by which it stops if the view is visible and starts automatically when the view is visible. This is why we are setting the owner in the init method. So, if you have autorefresher running on view A and B; and the user is viewing view B, then only view B is refreshing and when the user moves to view A; view B stops refreshing and view A starts.

Special thanks to Easwar for making this idea work! This component might come in handy for many . It sure saved a lot of effort for us . Check it out.

Note: The demo is very basic. All it does is gets the time every 3 seconds and updates the label in the view.

[ Demo | Source | ASDocs ]