Air HTML based dynamic image display issue

I’ve recently started building my first html based Air application using jQuery and have came across this very bizarre image issue. So here’s the scenario, I’ve got a text link with a image background attached with an onClick function, so when a click event occurred, the image background changes to another image. Now on a normal browser that would work fine but when I ran that in an air environment, the second image just wouldn’t load. I’ve double checked the syntax and even tried using a CSS class that contains the background image and using jQuery to add the class to the link upon onClick event. As expected that didn’t work!

After hours of testing and googling, I have came to a conclusion that jQuery can’t dynamically load images in an Air environment. So what I had to do was to pre-load all div elements with all the required classes on the page for the text link and that will pre-load all the images. Therefore when an onClick event occurs, the background images are displayed. Problem fixed!

Though this is not the best solution but developers should be keep this in mind when developing your Air application, because it would seriously affect how you’ll build/structure your application and could potentially save you hours of head scratching and frustration.

2 databases in one CFQUERY

I discovered this a bit by accident. I was wondering if it was possible to query 2 MYSQL databases in the one CFQUERY as I had 2 tables that I wanted to join in 2 separate databases and instead of moving the tables in question into the same database I thought I’d have a play… here are the results:

Lets make things nice and simple and call the databases database1 and database2… it’s easier. I should also mention that the 2 databases are located on the same MYSQL server and are accessed with the same user account. I have a Coldfusion datasource connected to database1 called database1connector. Here is the query and the syntax, it’s all about aliases people!

<cfquery name="q" datasource="database1connector">
	SELECT tb1.name,tb2.address
	FROM table1 tb1
	INNER JOIN database2.table2 tb2 
		ON tb2.id  = tb1.id
</cfquery>

Note that I include the second database by name in the join clause, simply referring to it by ‘databasename.’ then the table name. Note that I don’t use the ‘databasename.’ notation for the database being accessed via the CF datasource (the first database, ie database1 in the above example) as it will error.

I haven’t tried it but I am guessing that it would be possible to essentially join multiple databases using this same setup, give it a go!

Quick Tip – cf Initial Caps

Ever have a lower case string and needed the initial letter of each word to be in capital? well I did and luckily found a nice regular expression via google.

rereplace(“this string is all lowercase”, “(\b\w)”, “\u\1″, “all”) would produce ‘This String Is All Lowercase’

problem solved.

Regular Expressions in MySQL??

The other day while I was walking to work I found myself day dreaming. As my thoughts wondered I dreamt of a perfect world where you could use regular expressions whenever, wherever you liked.

Once arriving at work I was back to reality not everything in life can be a regular expression!

As I worked away writing some boring queries, I figured I might liven up my day and try using regular expressions to improve a query. After some research, much to my surprise I found that MySQL could handle regular expressions… maybe my day dream was coming true.

In my case I was looping over a list and comparing with another list found within the database, previously I had been using numerous ‘LIKE’ statements to match the two lists (see below)

<cfquery name="qData" datasource="#application.dsn#">
 SELECT *
 FROM tableName
 WHERE status != 'Archive'
 AND
 <cfset iCount = 1 />
 <cfloop list="#arguments.groups#" index="i">
 <cfoutput>
 (availability LIKE '#i#,%' OR availability LIKE '%,#i#' OR availability LIKE '%,#i#,%' OR availability = #i#)
 </cfoutput>
 <cfif iCount LT listLen(arguments.groups)>
 <cfoutput> OR </cfoutput>
 </cfif>
 <cfset iCount = iCount + 1 />
 </cfloop> 

 ORDER BY #arguments.sort# #arguments.sortOrder#

 </cfquery>

After some messing about with regexp (and some help from my boss) I was able to reduce this to a simple regular expression so my query became.

<cfquery name="qData" datasource="#application.dsn#">
 SELECT *
 FROM tableName
  WHERE status != 'Archive'
 AND
 <cfset iCount = 1 />
 <cfloop list="#arguments.groups#" index="i">
 <cfoutput>
 availability REGEXP '[^0-9]*(#i#)[^0-9]*'
 </cfoutput>
 <cfif iCount LT listLen(arguments.groups)>
 <cfoutput> OR </cfoutput>
 </cfif>
 <cfset iCount = iCount + 1 />
 </cfloop> 

 ORDER BY #arguments.sort# #arguments.sortOrder#

 </cfquery>

Next time you are writing a query take a second to ask yourself is this a good time to try out regexp? and hopefully the answer will be yes.

Faster UUID creation in Farcry 5.1x and above…

It’s simple and makes a whole bunch of sense, if UUID creation in coldfusion was faster then farcry will be faster given that it seems to use it quite a bit. Unfortunately the native CF UUID creation is really quite slow which is very well documented and does not need anymore coverage, if you want to find out why then use google.

Fortunately the guys at Daemon have decided to make it nice and easy to use their UUID method for generating UUIDs if you are using farcry 5.1x and above by simply swapping any instance of createUUID() with application.fc.utils.createJavaUUID() , that’s it!

This new method checks for the existence of 2 separate java libraries (depending on your version of JRUN) that can be used to create UUIDs before falling back to the native CF UUID method. If one of the 2 java libraries exist then you should notice a significant performance gain where the createUUID() method has been replaced because the java versions are so much more efficient, eg an import script.

Edit dynamic object in Farcry data library

Ever wonder how great it would be if you can edit the content of an object that you have selected in the library? Well now you can! By adding a form tool attribute ‘ftAllowLibraryEdit’ into your CF property such as below, it allows you to individually edit each object.

<cfproperty ftSeq="15" ftwizardStep="Body" ftFieldset="Relationships" name="aRelatedIDs" type="array" required="no" default="" ftJoin="dmNavigation,dmHTML,dmNews,dmEvent,dmFacts,dmLink" ftLabel="Associated Content" ftAllowLibraryEdit="true" />

Once you have included the new attribute, update the application. You should see a new button named ‘Edit Item’ appearing next to the ‘Remove Item’ button.

Regular Expressions

Regular Expressions are your friend. Once you’ve learn the dark art, you’ll wonder how you ever got by without. It does take a little time and some mastering however. Here are a few links to get you started on your way.

Farcry MYSQL Table Name Case Fixer

Annoyingly, depending on the setup of the MYSQL server at your host (and more specifically if they host their MYSQL server on a Windows box) the case sensitivity setting of the database may be set to be ‘case insensitive’… which is a pain if you are moving from a Linux MYSQL server to Windows and back etc because Farcry will not think that any of the object tables have been deployed along with all sorts of other issues. So to get around this issue I wrote a script that produces a nice bunch of sql statements to plant into your MYSQL GUI (eg. sqlYog) and it will rename all the tables back ito the case expected by farcry. This beats the heck out of doing it manually…. zippedy doo!

<cfset lcoretables = "container_aRules,dmExternalGroupToPolicyGroup,dmGroup,dmPermission,dmPermissionBarnacle,dmPolicyGroup,dmUser,dmUserToGroup,fqAudit,refCategories,refContainers,refDSAS,reffriendlyURL,refObjects,statsCountries,statsDays,statsHours,statsSearch" />

<cfloop index="i" list="#lcoretables#">
	<cfoutput>ALTER table #lcase(i)# RENAME _#i#;</cfoutput>
</cfloop>

<cfloop index="i" list="#lcoretables#">
	<cfoutput>ALTER table _#i# RENAME #i#;</cfoutput>
</cfloop>

<cfset lTypes = "#structKeyList(application.types)#">

<cfloop list="#lTypes#" index="st">
	<cfoutput>ALTER table #lcase(st)# RENAME _#st#;</cfoutput>
</cfloop>

<cfloop list="#lTypes#" index="st">
	<cfoutput>ALTER table _#st# RENAME #st#;</cfoutput>
</cfloop>

</cfset><cfset lRules = "#structKeyList(application.rules)#">

<cfloop list="#lRules#" index="st">
	<cfoutput>ALTER table #lcase(st)# RENAME _#st#;</cfoutput>
</cfloop>

<cfloop list="#lRules#" index="st">
	<cfoutput>ALTER table _#st# RENAME #st#;</cfoutput>
</cfloop>


<cfloop index="i" list="#lTypes#"></cfloop><cfloop collection="#application.types[i].stProps#" item="st"><cfif application.types[i].stProps[st].metadata.type is 'array'>
	<cfoutput>ALTER table #lcase(i&"_"&st)# RENAME _#i&"_"&st#;</cfoutput>
</cfif></cfloop>

<cfloop index="i" list="#lTypes#"></cfloop><cfloop collection="#application.types[i].stProps#" item="st"><cfif application.types[i].stProps[st].metadata.type is 'array'>
	<cfoutput>ALTER table _#i&"_"&st# RENAME #i&"_"&st#;</cfoutput>
</cfif></cfloop>


<cfloop index="i" list="#lRules#"></cfloop><cfloop collection="#application.rules[i].stProps#" item="st"><cfif application.rules[i].stProps[st].metadata.type is 'array'>
	<cfoutput>ALTER table #lcase(i&"_"&st)# RENAME #i&"_"&st#;</cfoutput>
</cfif></cfloop>

<cfloop index="i" list="#lRules#"></cfloop><cfloop collection="#application.rules[i].stProps#" item="st"><cfif application.rules[i].stProps[st].metadata.type is 'array'>
	<cfoutput>ALTER table _#i&"_"&st# RENAME #i&"_"&st#;</cfoutput>
</cfif></cfloop>

Tree Inspector, Version 0.51

Good news for children everywhere… Tree Inspector now alerts you when you are with the wrong parent!

Ever thought your navigation node was appearing under the wrong parent node?

Well the updated Tree Inspector helps ease your anxiety, take a look at the image below.

In the case above you will see that the footer nodes parentid does not match the utility nodes objectid. There are two possible causes for this and I will explain them and the fixes below.

1. The footer node is underneath the wrong parent; in this case you would simply update the nLeft and nRight (as normal) so that the node jumps underneath the correct parent node.
2. The footer node is underneath the correct parent, but for some reason the parentid in the database in wrong; you would need to manually update the nested_tree_objects table so that the footer nodes parentid is the same as the utily nodes objectid.

Have a shot at using this release and if you have any thoughts / improvements please post them here.

Simple farcry object debugging

Now and then when building a custom farcry object you might get the error ‘Element [insert object name] is undefined in a CFML structure referenced as part of an expression.’ upon accessing one of its methods by using the application scoped path eg:

createObject("component",application.types['insert type name here'].typepath)

Basically, this means that during the initialisation of the farcry application there was some sort of syntax error in the farcry object and was not able to be referenced in the application scope.

The simplest way to debug this is to make a small test file, put it into the webroot and call the object directly eg:

<cfset o = createObject("component","farcry.projects.projectname.packages.types.objectname") />
<cfdump var="#o#" />

Run the test file and it will try and create the farcry object and crash letting you know where the problem lies. All you have to do is fix the problem until you are able to run your test file without it crashing, then update the farcry application and boomshanka, all will return to a perfect state of harmony.