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Using Google Maps Places API and ColdFusion's CFMAP to render places of interests

Google announced the Places API recently at Google I/O (2011) and I was looking into this, to see how this API can be used in conjunction with ColdFusion maps created with CFMAP. The Places API can be used to retrieve place information which includes: Places of interests such as parks, restaurants, hospitals which are nearby to the users location. More detailed information on the place, such as the address, phone number etc,. The API can also be used to perform check-in at a particular place and to add\delete a place. These check-ins can then be used to evaluate the popularity of the place. In this post I'll explain how to retrieve the places of interests and displaying the same on a ColdFusion map using CFMAP.

Custom validation messages for HTML5 Input elements using the constraint validation API

HTML5 has introduced several input types such as EMAIL, URL, RANGE, SEARCH, DATE, TIME, etc,. Most of the modern browsers have implemented them and are ready to be used in a HTML document. Another exciting feature introduced in HTML5 is the form validation. Instead of writing JavaScript to validate users input, browsers can now validate it and show an appropriate message if the validation fails. The validation message is shown in line with the field for which the validation has failed. The default error message is shown when the validation fails. In this post I'll explain how these error messages can be changed.

Submitting Form using FormData object in HTML5 using XmlHttpRequest Level 2

The other day I had posted on uploading a file using XmlHttpRequest 2 and tracking the progress of the file upload process using the progress event on XHR2 object and the progress tag. Another enhancement added to the XHR2 specification is the introduction of FormData object. Using the FormData object, one can create a set of key-value pairs and send them as form data in a XHR request. The FormData object is passed in the send() method of the XHR object:

Auto Insertion of Tag attributes and Function arguments in ColdFusion Builder 2

The Editor is the most important feature in an IDE and the code assist features in the Editor helps in developing applications quickly and hence help in increasing the productivity. One of features is the 'auto insertion of tag attributes'. Most of the tags in ColdFusion have a mandatory attribute, for example the attribute 'name' is mandatory when using the cffunction tag. In ColdFusion Builder 2, these attributes are auto inserted i.e. when a user types in the cffunction tag and invokes code assist (using CTRL + SPACE) the name attribute is auto inserted. auto insertion also works for function arguments wherein the required arguments are auto inserted. Auto Insertion of Tag attributes As explained above, the mandatory attributes are auto inserted whenever the code assist is invoked for tags such as cffunction : In the above picture, code assist for cffunction is invoked and the tag is selected from the list. This would auto insert the required attribute 'name'

De-obfuscating javascript code in Chrome Developer Tools

I had blogged about JavaScript debugging with Chrome Developer Tools  some time back, wherein I have explained how these developer tools can help in debugging javascript code. Today Google Chrome 12 was released and my Chrome browser was updated to this version. As with every release, there have been some improvements made on performance, usability etc,. One feature that stood out for me is the ability to De-obfuscate the javascript code. What is Minification? Minification is the process of removing unnecessary characters such as white spaces, comments, new lines from the source code. These otherwise would be added to make the code more readable. Minifying the source code helps in reducing the file size and thereby reducing the time taken to download the file. This is the reason why most of the popular javascript libraries such as jQuery are minified. A minified jQuery file is of 31 KB in size where as an uncompressed one is about 229 KB. Unfortunately, debugging minified javascript f

Getting notifications of Network Status changes using online and offline events introduced in HTML5

I was working on an online\offline application, wherein I wanted to display a set of records stored in the local database to the user when he goes offline. The only way to determine the network status is to send a XHR request to the server at particular time intervals (polling). If the server responds back with some data it is understood that the user is online. However, I came across two event listeners 'ononline' and 'onoffline' which are triggered when the network status changes.

ColdFusion's CFDIV tag can be used to output HTML5's semantic tags

HTML5 has introduced several semantic tags such as HEADER, FOOTER, SECTION, ARTICLE, ASIDE, NAV etc,. The rationale behind creating these structural tags is to divide the web pages into logical parts with tags that are descriptive of the type of content they contain. Before HTML5 the div tags were used in creating blocks of content in a HTML document. Recently, I was having a conversation with one of my team members from whom I learnt that the CFDIV tag can be used to output these semantic tags. The CFDIV tag has an attribute  'tagname' . This attribute can be used to specify the HTML container tag i.e. one can specify tagname="header" to output the header tag. Similarly the tagname attribute can be used to specify other HTML5 semantic tags. Why should I use CFDIV tag to output the semantic tags? Well, this is an obvious question you are likely to ask yourself before you write the CFDIV tag. It is not so obvious to one who uses CFDIV tag in their day to day de

Drawing paths on Google Maps, the Indiana Jones way

I was looking into the Google Maps API the other day and came across some APIs which are really cool. I came up with a use case to show path from the current location to a particular destination entered by the user. I was also trying to achieve that Indiana Jones like effect on the map i.e. to show an animation of the path being drawn on the map. The idea here is to show the moving path until the destination is reached and also to pan the map accordingly. Unable to display content. Adobe Flash is required. As seen in the video, a marker is added to the map specifying my current location (Bangalore, India). The current location data is retrieved using the HTML5’s Geolocation API. Once the latitude and longitude information are available, a marker can be added to the map. You can now enter one of your favorite destinations in the text box provided and click the Submit button to see a path drawn from your current location to the destination. The path is drawn using the Google map