David Harris's Technology Blog

Getting Red from my color

Fri, 18 Dec 2009 04:58:00 -0500

I have a situation where I want to manipulate colors in flash. The idea is that the colors will cross fade nicely from one shade to another. While you can define colors like this: 0xef556ef that is stored as a unit data type. Looking at the above string, it's 8 char in length. The first two "0x" tell flash to treat this string as a hexadecimal value. the next two "ef" are the red value, the next two "55" are green and the last 2 "ef" are blue. Given the above value, I wanted to get the red shade of it, and only the red shade. This is what I came up with:



var myColor 		: uint = 0xef556ef

//convert the color to a string on a hex base and get the first 2 chars with "0x" at the front

var redValueString	:String = "0x" + myColor.toString( 16 ).substr(0,2);
				
trace( redValueString );

//convert the sting to the int value

var redValueInt		: int = int( redValueString );
				
trace( redValueInt.toString() );

This does give me the result, which is good, but I'm no flash pro, so is there a better (right?) way to do it? Feel free to tell me if there is!

CfObjective Downunder

Thu, 29 Oct 2009 15:05:00 -0500

I've been a bit slow in blogging, but thanks to a http://www.cfobjective.com.au/go/about-us,hard working team, CFObjective is coming downunder! They have secured a http://www.cfobjective.com.au/go/speakers,stelar line up of speakers, from both down under and up-over! CFObjective is "The Only Enterprise ColdFusion Conference", so expect a lot more than intro sessions here! Website: http://www.cfobjective.com.au/ Twitter: http://twitter.com/cfobjective_anz

Frameworks: Whats good about them, whats bad about them.

Thu, 29 Oct 2009 14:54:00 -0500

Frameworks: Whats good about them, whats bad about them. In my years programming, I've always advocated the use of frame works. While I have only every really used a handful of them myself, (across CF,PHP and Flex) there are underlying principles around frameworks that really appeal to me. But there are things about using frameworks you need to keep in mind. But first, some of the good things (a non-complete list): 1. Most frame works have the MVC paradigm at their heart. This is GOOD 2. Force some degree of fore-thought before launching in to code 3. If you use a documented framework consistently, handing over of projects is simpler. (key word "documented"! ) 4. Enforces a structure to your code base, which, once you understand it, *usually* means you can de-bug it better Now the bad things (also a non-complete list): 1. You are trusting code you may not fully know, or even blindly trusting this code. 2. Frameworks are not "silver bullets" that make you problems go away. 3. "Roll your own" frameworks are often badly documented, so hand over can be a real nightmare 4. You can get (feel?) trapped in a framework if it starts to fail you in anyway 5. There is no "perfect" framework. All have pros and cons. You'll need to find them and work with them. I used to say "The more something does for you, the less you can do with it". Of the past 5 or so years, this statement is less and less true, as there are some very comprehensive frameworks out there that do a very good job of empowering you to do what you need to do, while doing a lot of under-the-hood stuff too. To expound on a couple of the "Bad things" While trusting code you don't "know" isn't always bad, it is bad if you start having issues with it. You are faced with some options. - Abandon it - Dig in to it and "learn" it so you can fix it - Work round it's limitations While I like using frameworks where I can, there is always the "can-o-worms" fear that maybe framework "ABC" or "XYZ" isn't quite a clever as I was expecting under the hood... On the non-silver bullets of frameworks: sometimes it seems (particularly in the "Which framework is king" ~~flame wars~~ discussions), that people are looking for a framework to make all the hard work go away. Unfortunately this isn't what frameworks are for or about. Which ever framework you pick, you will have to learn how it works. You will be slower with it than not using it at first. You will be faced with learning the framework AND solving the problem(s) you are developing to. But... - the more you use it, the faster you will get at it - When faced with problems, you'll know how to solve them within the framework, so you time isn't eaten up with "what goes where", but you can focus on the problem at hand. While the above is by no means complete, I had to let it out somewhere! Thanks for listening! PS: I have nothing but absolute respect and props for the men and women who give up so much of their (usually personal) time to create/code and manage any framework! My hat is off to them! PPS: One other thought: A lot of what I've said above is also true for application platforms too!

Adobe Community Road Show Coming to Auckland!

Tue, 23 Jun 2009 19:32:00 -0500

This Thursday http://www.cfug.org.nz/ and http://www.fxug.org.nz/ are hosting an Adobe Roadshow event with http://www.markszulc.com/blog/2009/06/22/flash-catalyst-builder-cf-tour-headed-to-auckland-nz/,Mark Szulc. Come along to hear more about Flash Builder, Flash Catalyst and CF9! I will attempt to broadcast the meeting on http://experts.na3.acrobat.com/nzcfug/, all going well! Related Links: http://groups.adobe.com/posts/1b5f77b054 http://nzroadshow.eventbrite.com/ http://labs.adobe.com/ See you there!

AIR Widget: Snow Reports to your desk top!

Mon, 15 Jun 2009 18:59:00 -0500

The last while I've had the fun of developing an AIR app for one our clients. A pretty simple little widget to let you know the Snow conditions on the Ski fields in New Zealand. So, if you wish you where here skiing, download this widget to make you green! http://www.summitlager.co.nz/widget.html I made use of http://code.google.com/p/flexcairngorm/ and a little http://www.degrafa.org/ in there too! Thanks to the design team for making it look so cool. Enjoy!

NZCFUG this week: Mango Blog 101

Tue, 02 Jun 2009 12:20:00 -0500

Just a quick note to announce what this months NZ CFUG topic. I'm going to do an intro to http://www.mangoblog.org The meeting will be broadcast live @ 6pm NZ time, so feel free to log in an watch if you like! I'll put the Connect link up here: http://cfug.eventbrite.com/ before the time, so watch that space!. The reason we are covering this is that there was a general interest in the group to review (free) pre-baked CMS solutions. While Mango is really a blogging tool, it can be used as a CMS too. In the upcoming months I am hoping to get Presentations from http://www.getmura.com/,Mura( CMS formally known as ~~Prince~~ Sava) and http://www.farcrycore.org/,Farcry. If you know of other free ColdFusion CMS solutions, please let me know so I can include them in the line up!

Simple Example of Randomizing the order of an array in ActionScript

Thu, 16 Apr 2009 15:10:00 -0500

Just got asked this by a work mate and after asking Mr Google and looking at the Array Documentation came up with this (Flex based) example, so thought I would share :-)

ColdFusion and constants - how do you do them?

Sat, 04 Apr 2009 21:05:00 -0500

I've been working on a project a bit lately and found I've had the need to use some constants. This has gotten me thinking how to implement them. When work in Flex, I use the http://code.google.com/p/flexcairngorm/,Extensions for Adobe Cairngorm and when creating your custom events involves you declaring constants in the event. The consts in the event are related to the Event type. The idea behind constants is that this is information that *will never change*, hence the name "constants" :-) In the CF application I've been working on, UUIDs are used, and there is no way you can call a UUID "human readable", so this can make code harder to understand when you see something like:

If you want the person who reads this code later understand which page that is with out having to pull the application apart (and hair out too sometimes), you might to this:

That way the name of the variable will indicate *what* that UUID value indicates. With me so far? "But Dave, my application has more than one template and I don't want to have to do that every time I want to send a user to the info page, and what happens if the UUID of the info page changes?" you cry. Well, why not have a single "thing" that stores all your constants that you can store in one place and use everywhere? What I started doing here is I created a "Const.cfc" that had getter functions on them to return the constants. EG:

So the previous code can be done as:

(to be honest, I'd actually drop the "get" on the function name and just call it "InfoPageUUID", as it is a const and there is no "set", so why "get"?) (Another note: I'd usually declare/call the function in all CAPS too, as this is the "standard" way of naming constants) The above relies on "oConst" being created, which could be stored in application scope for example. What I didn't like about this is that the actual value is hidden from my old friend "cfdump", and if I have alot of constants I can't see their values in one hit. This lead me to the "this" scope of my CFC(s). Something like this:

...which them means the example code can be written like this:

Before you cry "But people can change the values in the 'this' scope and break stuff!", I've always thought if people want to do that, it's up to them, but don't come running to me if it breaks! (Also, CFCs are not secure at all anyway! see related entry) The two things I like about using the "this" scope for constants are:

1: You can see all the values if you cfdump it
2: If you CFC has functions, you don't have lots of functions to work out that don't really do anything

Let me explain the second point a bit further. Imagine I have a DB table that stores information of pages on my site. My CFC has functions to work with this data. In my application I have 1meeeeeeelllion UUIDs to do with various parts of the application, that are used in various ways, that would help the readability of my code if they are stored as constants. This would render the "One Constant.cfc to rule them all" a bit hard to manage. What I have been doing is storing the UUIDs to do with that part of the application in the CFC that deals with that part of the application. EG:

by default (CF8 I think...) I would see all my constants at the top and all my functions would be collapsed. Given the above code uses no frameworks and if any of you managed to read all my brain dump, what thoughts do you have on the above and/or how have you approached ColdFusion constants? Disclaimer: all the above code is psedo code and hasn't actually been tested, but feel free to point out syntax errors etc. I may change it, I may not...

Transfer: Something I like about it.

Mon, 02 Mar 2009 19:55:00 -0500

I've been looking in to Mark Mandel's http://www.transfer-orm.com/,Transfer bit since he presented to the http://www.cfug.org.nz end of last year. One thing (of the many things) I like about it is the XML config file. Why do I like it? 2 reasons. 1. The fact you can introduce some form of package.class hierarchy to the Database, so flat database's can be organized better EG:

So this means I call my "myclass" like this:


transfer.getTransfer().new("mypackage.myclass");

2. The second reason is: I CAN COMMENT THE XML! Why is this good? I'm sure we have all returned to database tables with a few to many columns and tried to would out what "status" column and "anotherStatus" column actually relates to in the business logic of the application. This process involves digging through code and random comments. With the XML config of transfer, a simple comment on the property can explain it so the next person who needs to work with it knows where look to find out what the class (db table) is for and what purpose the property servers. Hopefully I'll find the time to blog some examples on Transfer later. EG: Event model and decorators

NZ CFUG: Mark Mandel on Transfer

Tue, 04 Nov 2008 18:27:00 -0500

Only 2 days till the next NZ Cfug meeting. This month we are going to have Mark Mandel giving us his "Introduction to Building Applications with Transfer ORM" presentation live via Adobe Connect. We attempted to have this last month, but due to technical issues last month [cough]VPN[cough] Mark agreed to give it this month. This month we are meeting for the first time at http://projectpartner.com/,ProjectPartner, so a big thank you to them! The meeting will be broadcast via Connect on the URL http://experts.na3.acrobat.com/nzcfug/, so feel free to sit in if you are round @ 6pm (NZ time) on the 6th November. If you RSVP (remote or in person) and are based in NZ, you'll be in the prize draw too! RSVP: http://nzcfug.eventbrite.com/ See you there!

Adventures in jQuery

Thu, 03 Jul 2008 12:41:00 -0500

The last week or so I've had the pleasure of working deeply with http://jquery.com/,jQuery. And I mean that, it's been a pleasure. Once you get used to the 'style' of how it works, it makes sense and has a consistent coding experience. I've worked mainly with the core and the ui.jquery libraries, with fileupload thrown in. In the mix is also , and they have all played together nicely (so far!) I've got jQuery adding and removing custom DOM elements on the fly, while updating information on the server, uploading and deleting images and also maintaining the structure of the form so that when it is submitted in the usual "post" manner, the server knows what to do with the data it receives. So all in all I've had a good experience with it. Things it has helped me understand is the use of "anonymous Functions" (I think that is what they are called) EG:


$("#myelement").hide();

will hide the element with the id of "myelement" now the "hide" method will accept an argument of a function that it will call when it has completed. Commonly called a "callback", so i we had a function like this:


function alertme(){ alert('me'); }

you could call that function when hide was complete like this:


$("#myelement").hide( alertme );

so the function has the name "alertme", so is not anonymous. To use an anonymous function to do the same thing, this is what you would do:


$("#myelement").hide( function(){ alert('me'); } );

You can also do this in Flex. eg: rather than:


addEventListener( "SomeEvent" , someFunction );

You can go:

 
addEventListener( "someEvent" , function( event: Event): void { [do stuff here] } );

While you can put as much in you function as you like, I did find it makes code a bit hard to read. One thing that works, but somehow feels wrong, is that the anonymous functions have direct access to the variables declared in the calling function. eg:


function myFunction()
{

	var someString = "bob";
	$("#myelement").hide( function(){ alert( someString ); } );

}

This seems to be true of both JS and AS. I guess this is because the function itself belongs to the function it is being called in, so has access to the variables called in there... So all in all I've enjoyed getting to know http://jquery.com/,jQuery, and suspect it's the beginning of a beautiful friendship! ...but, I still prefer Flex!

CF8 Ajax Goodness - Ray Camdens Recording

Thu, 05 Jun 2008 22:07:00 -0500

Tonight we had the honor of http://www.coldfusionjedi.com,Ray Camden staying up till 1am his time to present to us @ 6pm NZ time. The meeting was the http://www.cfug.org.nz,NZ ColdFusion UG June meeting, and the topic was CF8 Ajax Goodness After a couple of technical issues (involving screen issues and incorrect Connect meeting rooms on my part...*cough*) we got the meeting under way. Ray, as always, gave a great presentation which promoted good discussion in the group afterwards. So a big thanks to Ray for his continued giving of time and energy to the community! The recording URL is https://admin.adobe.acrobat.com/_a200985228/p21985414/ and I have also added it to http://carehart.org/ugtv/list.cfm,UGTV Enjoy!

Ray Camden Presenting to New Zealand CFUG

Fri, 30 May 2008 21:52:00 -0500

With great appreciation, I am happy to announce that Ray Camden will be presenting to the http://www.cfug.org.nz,New Zealand ColdFusion User Group live via Adobe connect. He is going to sacrifice sleep at 1am his time to present to us on Thursday 5th June. The topic is yet to be confirmed, so keep an eye on http://www.cfug.org.nz for the topic. The meeting will be broadcast ,recorded and open to all to join, so check out the CFUG website for details! This is the second time Ray has done this for us, and last time was a great success! Meeting Details: This month is being sponsored by Shift.co.nz and will be held at their offices RSVP: http://nzcfug.eventbrite.com/ Date Thursday, June 5, 2008 Time 5:45 pm - 7:00 pm Location Shift Offices, Level 3, National Equity House 75 Queen Street Auckland, 0100 New Zealand (Aotearoa)

ColdFusion 8.0.1 fixed my bug!

Wed, 30 Apr 2008 22:38:00 -0500

I while ago I logged a bug for the first time with in ColdFusion 8. http://www.harrisfamily.net.nz/devblog/index.cfm/2007/10/17/cfpresentation-and-attributeCollection-issue,Here is the entry about it. While looking over the 8.0.1 release notes I decide to check... and yes, at the top of page 15, bug number 70594 has been addressed! Thank you!

Transfer 1.0 ORM is released!

Mon, 28 Apr 2008 21:56:00 -0500

Just noticed this on a mailing list: http://www.compoundtheory.com/?action=displayPost&ID=303,Transfer 1.0 Release Candidate - Out Now! Well done Mark! Mark presented to the NZCFUG last year on TransferORM. I'll be downloading Transfer 1.0 soon to have take it for a spin!