The miscellaneous ramblings and thoughts of Dan G. Switzer, II

MouseIntent jQuery Plug-in

One common pattern I've seen in usability, is that users don't always have great control over their mouse. It's easy to accidentally overshoot a target area with you mouse, which is really frustrating with things like nested dropdown menus, where accidentally mousing away from a target area may end up collapsing/closing the open menu.

Giva's recently released the MouseIntent jQuery Plug-in which aims to give developers a way to control this behavior. It works by monitoring an invisible border around the element to see what the user appears to be doing. If a user quickly moves back into the original element, then then no mouseaway event is ever fired. The plugin has a number of settings that allow you to control the behavior—such as monitoring whether or not the user is still moving the mouse in the invisible border area.

I've used the plugin in one of our dropdown menus that has nested menus and it's really helped to improve our user's experience.

Maskerade Date Mask Input Plugin

Giva has released released a new plugin (Maskerade jQuery Plug-in) which can convert a normal text field into a power date mask input field. The plugin supports a large array of date masks (even quarters) and even supports copy/paste. Here's a list of some of it's key features:

  • Keypress validation (ie. you don't need to submit the form for the mask to be applied)
  • Full keyboard support, including number to text-date interpretation (eg. typing 6 for a month will show June) and number-entry interpretation (eg. typing 02 in a yyyy date field will be interpreted as 2002)
  • Full mouse support
  • Masks can be defined as attributes of the input field; individual jQuery mask calls are not needed
  • Includes time-mask capability, with a date or alone
  • Default values and masks set as placeholders in the input field
  • Ability to set min and max dates allowed on a field
  • Allows for enforcing relational validation (ie. date1 must be before date2)
  • Automatic adjusting for invalid dates (eg. Feb 29, 2001 is adjusted to Feb 28, 2001)
  • Each date/time part fully highlighted on focus
  • Automatic tabbing to next date/time part once interpreted (eg. typing 2 in a "mm" date part will automatically tab you to the next date part), which allows quick keyboard entry
  • Allows for dask masks by quarters (eg. Q1, Q2, etc.)
  • Ability to support multiple languages
  • Custom event handlers; for example, a single keystroke can be defined to change the date to the current date
  • Detach/attach Maskerade behavior from the element

We have actually been using this plugin in production for a long time with great success.

ColdFusion 9/10 generating hidden exceptions when using Images stored in RAM disk

We recently discovered an issue in ColdFusion 9+ when images that were temporarily stored in the RAM disk, but later removed would start throwing exceptions in the application.log, exception.log and coldfusion-out.log. The code itself would run just fine, so the issue is a bit masked because you won't see it unless you're monitoring your log files.

What we were seeing was a lot of errors like the following being thrown throughout our logs:

Could not read from ""ram:///797C39D0-CAE4-21F9-D573CFDC3FE7482E.jpg"" because it is a not a file.

When we tracked down why the log entries were being written, we discovered that the following workflow was causing the problem:

  1. Called a UDF to return a reference to a ColdFusion image object. The UDF would:
    • Use the RAM disk to convert the image into a common image format
    • It would then remove the temp file from the RAM disk
    • It would scale the image
    • Finally, it returned a reference to the ColdFusion image
  2. We would then attempt to write the image object to disk

It was when trying to write the image to disk, we'd start to see 3 exceptions being logged, but the code would generate the expected output. What appears to be happening, is that internally ColdFusion is trying to access the original "source" of the file for some reason.

What we did to fix the issue, was to return a new copy of the image using imageNew(imageGetBufferedImage(source)). What this does is create a copy of the image that no longer references any file on disk, but creates an image purely in RAM.

I'm sure this isn't a very common problem, but if you found that you're using Dave Ferguson's ColdFusion 9 PNG image processing fix you may find yourself running into this issue.

I've filed a Bug #3690487 with Adobe. This problem does affect ColdFusion 9 and 10, so if you think Adobe should fix it, make sure to vote it up!