Oracle, Apex, and other musings.........

Apex 4.0: SQL in Plugins and seeing Stars.....

2010-03-16T16:47:00.000Z

This is my first post in a few weeks as I've been a little busy with work recently, which is just criminal as I really just want to play with Apex 4 EA2. Oh well, bills have to be paid and children fed I suppose.

Anyway, let's cut to the chase. There is a nice feature of Apex 4 plugins (which I'm pretty sure wasn't working correctly in EA1) where you can create a custom attribute of type 'SQL Query'. I've added this to the Range Slider plugin I use on my Online Store demo for the min and max default range values, as you can see below:

Anyone using the plugin can write SQL statements for these attributes, and the good part is that they will be parsed when the changes are saved. You can see in the screenshot below that I have set the Default Range Min Value to the mimimum selling price and the Default Range Max Value to maximum selling price. I should, of course, set the Minimum Value and Maximum Value to also be 'SQL Query' attribute types and set them to be slightly smaller and large that the min/max selling prices, but I haven't got around to that yet. Sorry. The plugin can be found here.

And what does he mean by '....seeing Stars' in the Blog post title, I hear you ask? Well let me explain.

You may have noticed that I have used a Star Rating on my application, which is taken from Patrick Wolf's excellent sample Plugin application which can be found via this blog post. I have taken that Star Rating plugin and used some jQuery magic to dynamically update the list of products in a similar manner to the Range Slider and Categories in the Refine Search region. Click on a star and it will displ;ay products that have at least that rating as a minimum. So clicking on star 3 will display all products with ratings of 3, 4 or 5 stars. You can also click on the reset button to the left to set it so that all products are displayed including those without a rating. If you want to know how to do this in more detail, then please let me know and I try and find the time to explain.

At some point I promise I really, really, really am going to smarten the demo up. Bye for now.

Apex EA2 update

2010-02-26T22:23:00.000Z

To see the new style Plugins use this link to the Plugins Application provided by Patrick Wolf:

Plugins Application

I've managed to copy the syntax used in some of these plugins to update those on my Online Store demo.

I've still need to upload some images and it looks like there are a few issue with my schema, but generally the app appears to be working. So, in general it looks like EA1 apps can be imported into EA2 with little need to change anything.

Apex EA2 is now available

2010-02-26T21:45:00.000Z

The good news is that it appears that applications exported from Early Adopter Phase 1 import ok in the new EA2.

The bad news is that plugins have had a bit of an overhaul. It looks like the PL/SQL code used to construct a plugin now uses functions rather than procedures. So back to the drawing board for some of my online store demo plugins!

Can anyone from the team shed some light on what I do with 'apex_plugin.t_page_item_render_result' or 'apex_plugin.t_page_item_validation_result', please?

Static Region Id's and Ajax Fun

2010-02-19T18:43:00.001Z

More Online Store demo shenanigans for you. A bit dry this one I'm afraid.

A couple of days back I decided to export/import my Online Store demo, and whilst viewing the new imported version of the application found it to be completely kaput. It didn't take long to realise that I had made the mistake of hard coding region id's in some of the Javascript. Well, I thought this will be easy to fix as I can just utilise Static id's instead in my regions and in place of #REGION_ID# in templates. So far, so good, but then I realised that the Ajax refreshing of the Products and Shopping Basket regions is done using calls to html_PPR_Report_Page and $a_report, and both these require the internal numeric region id as a parameter. As far as I know neither recognises the Static id (please correct me if I am wrong). Doh!

I get around this by creating hidden items (i.e. P1_PRODUCT_REGION_ID) based on a SQL query that uses the Static id to get the 'real' internal numeric ID. The following SQL does the job:

SELECT region_id
FROM   apex_application_page_regions
WHERE  static_id      = 'PRODUCTS_REP_REG'
AND    page_id        = v('APP_PAGE_ID')
AND    application_id = v('APP_ID');

All well and good I thought, but then I found another issue. In the main Products region if the search is refined so that no rows are returned then instead of displaying the 'When No Data Found Message' wording from Report Attributes section it displayed the whole page embedded within the region. Double Doh!

Again, it appears I had hard coded the internal region id into the 'When No Data Found Message' section, something like:



 - No Products Found -

This had worked nicely in the orginal app from which the export came, as in lieu of a 'No Data Found' template, I simply copied the div and table tags that would appear if rows were returned in the Products region. But now it was useless. Therefore, I employed the following instead to fix the problem:




- No Products Found -

This simply embeds the value of the P1_PRODUCT_REGION_ID (the internal id of the product region) into the HTML. Voila. It works a treat, and no hard coding of id's in sight.

So, not a lot of visible progress on the store this week. Although, I have managed to make the site look similar and work the same way in IE, FF and Chrome.

Hopefully next week I can start to look at improving the look of the store. I also want to change the templates to be Div based as per the new Apex 4.0 theme.

jQuery Zooming

2010-02-12T16:11:00.001Z

Many online stores offer potential buyers the choice to view large version of images of products, but increasingly there is a tendancy to allow 'zooming' in on products to see more detail. Amazon allows this with many of its products, for instance.

There is a plugin for jQuery which does something similar (ish) which I've add to my store demo. Click on the product name for one of the products, I suggest the iPad or iPod Nano, to view this in action. In the overlay window, hover over the image and you will see how this works. Well this nifty little plugin is called jqZoom, but I also found a non-open source alternative that doesn't use jQuery called Magiczoom, which is used on a number of commercial sites.

You will notice that a few of the images are missing from the demo. With jqZoom, you need to store small and large versions of each product image, although the large image only gets loaded when you hover over the small image. Each image is stored as a Blob linked to the product. As I was loading up the images using the application I kept getting a 'ORA-01691: unable to extend lob segment.....' error, so I need to look into this.

Well Fancy that!

2010-02-08T14:44:00.001Z

I came across a jQuery plugin called FancyBox for creating nice "floating" overlay windows, which I have incorporated into my online store demo. Just click on the product name and it will display the details in a modal window.

It doesn't currently work in IE 6, although I'm not sure about later versions, so you're best viewing it in FF.

Range Slider Plugin

2010-02-02T20:12:00.003Z

I've spent a little time updating my online shop demo recently. I've still a long way to go but initially I am trying to get as much core functionality built into the search page, such as trying not to submit the page at all and do as much with Ajax as I can. From hereonin I think I shall refer to this as 'Ajaxifying' my application. Ok maybe not.

You can go to the demo here....Online Store Demo

Something to note. You can drag and drop the product images into the shopping basket and the basket inventory will update, but this doesn't work with pagination. If you use the range slider this will reset pagination and it will work again. Also note, that this page only works properly with Firefox, which I think maybe down to Apex 4 EA not yet being supported in IE (it doesn't work with Chrome either).

You will notice that I have created a new plugin which I have based on Patrick Wolf's slider plugin, but this uses 2 markers on the slider to represent a range of high and low. You can also specify default high and low values for the slider. You can get the range slider plugin here. (let me know if this link doesn't work). As plugins only return a single value, then the value returned will be made up of 2 values separated by a comma (ie '100,4500'). You will of course need to extract each value from the item you base on the plugin if you want to refer to them in a report Where clause.

I will post some more in the next day or so as I make other improvements.

(Thanks to Anthony for help with the live binding of the drag and drop/slider dynamic actions)

UPDATE: One thing I forgot to mention is that I added a plugin parameter for the range slider that allows you to specify a jQuery theme from a select list. This is not the most efficient way of applying themes to all jQuery based plugins on a page/application, but it gives you a flavour of what can be done.

So yes, it really is just a big iPhone.

2010-01-27T19:41:00.000Z

So, if, and it's still really an if at this stage, the iPad takes off in a big way (and you know how what happens next - designers/marketing/sales, etc buy them, take them to meetings, then everyone in the company wants one) this really is going to have an impact on how we design our web apps, Apex definately included.

It's one thing showing off a tiny iPhone version of an Apex application (just because you can), but it's going to be a reality that we are going to have to now design for mouse'less and keyboard';ess (well physical anyway) devices - welcome to the age of multi-touch.

Multi touch and web applications

2010-01-25T14:31:00.001Z

The award for the "worst kept secret of the last 12 months" will no doubt be awarded to Apple later this week after the unveiling of the iThingamy this Wednesday (27th). As I said in an earlier post, this is likely to herald the start of the era of the ubiquitous tablet computer, in part thanks to the success of the iPhone.

Love 'em or hate 'em, Apple certainly know thing or two about delivering objects of desire, but I can't help feeling that there will be a lot of dissapointment around if this story from The Register is true. It indicates that the tablet's OS may be the same as that on the iPhone, and not based around Mac OS. Considering that multi-touch is native to a 'fully blown' OS like Windows 7 and the cost of the Apple tablet is rumoured to be around $600-$800 dollars, then I wonder what impact this may have on its success?

Anyway, onto the main reason for this post, which is that I got thinking about multi-touch and web based apps in general. I was playing with one of my Apex applications on my iPhone. This app has a slider and drag and drop functionality, but of course neither of these work using the iPhone's Safari browser. So, I'm now intrigued by how this kind of functionality is going to work, particularly if Apple's device is just going to be a jumbo iPhone? Any thoughts?

Speaking of which, why is it that when I think of this tablet just being a big iPhone, does this image appear in my head:

Shop 'til ya drop, Apex 4 style.

2010-01-21T21:28:00.003Z

Bad title I know, but it's late here in the UK, so I hope you'll cut me a little slack?

Now I said I would update you on my progress with creating an online shop for my wifes business. So, this is what I have so far.

I've taken the original Online Shop packaged application, then modified and funked it up a little it using Apex 4 early adopter (if you haven't already then get yourself an account at Apex 4 EA). Specifically, I have used some of Anthony Rayner's excellent plugins from his recent blogpost, which I highly recommend that you use as a starting point. The plugins in question are those to create and control a slider and drag and drop.

Please visit my demo shop application and have a play around. It's obviously only a first cut, just to test drive some Apex 4 features, and is obviously a long long way off being useful. The features you may want to try are:

You can drag and drop products (the image) to the shopping basket and the number of items will increment.
There is a slider which can be used to view all products with the slider value as the minimum price. A bit of Ajax is used to reduce/increase the products displayed.
There is an autocomplete search box using the new Text Item with Autocomplete, straight out of the box.

If you want to play with the drag and drop, you will need to do this first as setting the slider renders this feature unusable. I will work on this, just not tonight.

Let me know how you get on, and if anyone is interested then I will blog again on how it was developed.

iSlate, iPad, or whatever it will be called

2010-01-19T16:33:00.000Z

Interesting article on the BBC News site regarding how Apple 'manages' controlled leaks.

It looks like a dead cert that Apple will anounce the iWhatever next week, and in doing so will arguably kick start the next generation of computing, that of the tablet based computer. This will be the start of the two horse race between Apples new device and other Windows 7 (with its native mutli-touch) based devices.

So, I'm thinking this can only be good news for us developers out there, as the low cost tablet (though low-cost may not apply to the Apple device) takes over from the low cost netbook. Modern web based applications are just crying out for devices like these, particularly the kind of business centric applications we Apex developers specialise in. I think Apex version 4, with a focus on easier Javascript development, and Ajax functionality, is going to be well positioned for development on these devices.

I'm interested to see what new Apex themes and code, particularly plugins, that take advantage of multi-touch abilities will start to appear in the future once tablets become more widespread. I'm not aware of any examples for the iPhone and the only technical info I could find is the presentation by Brian Spendolini, but I'm happy to be pointed in the direction of any others.

Eventually......

2010-01-19T08:00:00.007Z

Well just 3 years after creating an account on Blogger I am writing my first post. This of course is at a time when, we are told, blogging is dying (or should actually be dead now according to this Wired article from a little while back).

So, with this in mind, it means I will likely start some serious twittering in around another 2-3 years, long after the twitter dust has settled. I had come here armed with an arsenal of excuses, but to hell with those, I'm just going to get on with it.

You see, I'm coming to the end of a long'ish contract where again my Apex skills were called upon once again and, after it finishes, will probably spend some time building an online shop for my wifes business which supplies jewellery to other businesses, but wants to sell direct to consumers. I say 'probably' as what usually happens when I make plans in this way is that a nice little contract comes along which I start as the other finishes.

Assuming for now that this plan does happen, then I need to consider how I am going to go about this. As its an established business that I would be developing for, then we want something more than the usual limited template driven options available from some of the hosting companies. So, I had already started looking at other options, you know, the usual suspects - osCommerce, Zen Cart, Actinic, Avactis, etc, some of them highly configurable but most over complicated for what we need.

Then I got thinking, why not utilise the skills I have and create the online shop using Oracle and Apex. This makes complete sense. Apex is perfect for this - its sits in the DB so benefits from all the security that offers (I know, I know, there are security issues but I have that covered), there's enough hosting companies out there now, and with Apex version 4 I can take advantage of many new features (ie auto comlete text boxes, dynamic actions, jQuery, plus hopefully a whole raft of third party plugins that will be available). Plus, of course the Oracle Stor e is Apex based (though I suspect the development budget for that is a teeny bit more than we have).

So, that is where I am at the moment. I've taken a look at the Online Store packaged application and may use this as a starting point, but I'm interested in other peoples experience of doing a similar thing with Apex. Good or bad, any comment is appreciated, and I shall keep you posted with my progress.