Oracle & APEX Geekery

When developing an application in Oracle APEX, I usually have opened two browser tabs, one for the builder and one for the application I’m working on. This works fine, even though both tabs are using different sessions. The other day I noticed a strange annoying behavior using this approach: Each time I opened the application I was working on in the new tab, my builder session was expired. This behavior wasn’t related to the APEX version: it happened with my 4.2 installation running on a VBox as well as with my local installation running 4.1. I was rather puzzled, as I didn’t change anything on my local installation. Here is what caused it (thanks to Christian Neumüller for explaining): I ran into the so-called APEX Listener favicon-bug : On my 4.1 installation I was working on a new theme, build entirely from scratch, and on my 4.2 installation, I was playing around with a mobile application. What both applications (or better: themes) had in common: the lack of a favicon referen...

Maybe you have noticed it, maybe not, but the hover effect of the Normal Button template in the APEX Cloudy theme does not  work in IE. It seems it hasn’t been implemented. So if you want the hover effect in IE, here is the CSS snippet you need to to add to your template: .ie6 a.uButton:hover span, .ie6 a.uButtonLarge:hover span, .ie6 a.uButtonSmall:hover span, .ie7 a.uButton:hover span, .ie7 a.uButtonLarge:hover span, .ie7 a.uButtonSmall:hover span, .ie8 a.uButton:hover span, .ie8 a.uButtonLarge:hover span, .ie8 a.uButtonSmall:hover span, .ie9 a.uButton:hover span, .ie9 a.uButtonLarge:hover span, .ie9 a.uButtonSmall:hover span { background: url(#IMAGE_PREFIX#themes/theme_24/images/app_theme.png) 0 -400px repeat-x #DEDEDE; } This will only affect IE and will load a slightly lighter gray gradient background on the hover state of the normal button. Credits go to Shakeeb. Thanks!

Today (nov. 6th 2012), the book ‘ APEX Best Practices ’ written by Learco Brizzi, Iloon Ellen-Wolff and Alex Nuijten was finally released. I was curious about the book, for several reasons: I promised the book to the winners of my FifApex competition earlier this year I know all three authors and heard some stories about the process of making it As an APEX developer: what ‘Best Practices’ will the book advice Here is my first impression: There is more to APEX then just building pages, and this is where this book comes in handy. Installation , set-up , maintenance , versioning , deployment , printing , are all subjects elaborated in this book. ‘APEX Best Practices’ will help you planning and setting up your environment. Also the book talks about creating pages and reports as well, it’s not the usual step-by-step tutorial. It focuses on the structure of an application and the development process in general. The book contains an extensive chapter (probably written by...

I promised to publish about this subject to one of the attendees during my presentation at KScope 12 in San Antonio. I used this functionality in my demo application ( FifApex ) and it seems there is interest in how to do this. Most of the public websites like Facebook, LinkedIn, Twitter, Amazon or OTN do have it: an option to stay logged in, even if you closed the browser, so you do not have to authenticate each time you visit the site again. I’m pretty used to it and would be surprised if a website didn’t offer this convenient feature. OK, it’s not entirely secure, but, as I said, very convenient. I’m working on a “consumer” site/application, I’m building it with APEX and I want to offer this “remember me” option too. I knew an APEX based website that does offer this feature ( www.plsqlchallenge.com ) and I had a chat with the developer that implemented it’s login mechanism, Paul Broughton from Apex Evangelists . So, here my thanks to him for the original inspiration.   Or...

The build in jQuery UI Datepicker of Application Express is a very versatile component and it is very easy to configure the basic settings with the Page Item properties. One of the properties you can set, is the range of selectable dates by entering a Minimum and Maximum Date value. The “syntax” of these values is based on the jQuery UI Datepicker components date format capabilities, so this might be looking a bit awkward to us Oracle folks at first sight. Next to giving a static value or one of these Datepicker calculations you can reference an APEX Page Item to set the range values, which is a nice thing as we are able to calculate a range dynamically, based on some database value/calculations. The bummer is: the calculation only gets executed during the rendering phase of the page and changing the referencing Page Item’s value won’t change the Datepicker range. What you really want (yes, you do), is to be able to reference Page Items to control the Minimum and Maximum Date dynamica...

Tags van Technorati: apex , dynamic action , tabular form , add row , focus , cursor I just got the question from a fellow developer, how to focus the cursor to the first input field of a newly added row using the ADD button in a standard APEX Tabular Form. Actually, I would expect APEX to do this automagically. But it doesn’t. To implement this behavior is actually really simple.     For this example I create a simple tabular form based on the demo_customers table: This is what the form looks like when you click the “Add Row” button. As you can see, none of the input field has focus at this time. To focus the cursor on the first field of the new row (Cust First Name), I somehow have to change the behavior of the “Add Row” button. Let’s have a look at it’s definition: The click-action of the button is actually a JavaScript call: addRow();. Naturally I want to keep this action, but after this, I want to start an additional action that should set the focus to the input f...

When working with APEX you certainly want to use the APEX Listener. It’s a great piece of software and Oracle is committed to extend its functionality (Oracle recently release the beta version of the new APEX Listener 2.0 ). When installing the APEX Listener, you basically have two choices: run APEX Listener “Standalone” deploy the Listeners WAR file to one of the supported webservers The problem (at least, my problem): when using the APEX Listener on my laptop/desktop with my local APEX instance, I do not want to set up a whole webserver, just to be able to develop APEX applications. So I,’m choosing the lightweight option: Standalone! But the annoying thing about the standalone installation is, that I have to start the APEX Listener from the command line each time I want it to be available. It just would be so much easier to just have it as a Windows service, stating during system boot. Seems that an APEX developer from Poland, Andrzej Nowakowski , solved this problem for us and...

Tonight (CET) the European Football Championship kicks off. As with every EURO or World Championship I’m organizing a predicting game where you (Yes, you too!) can bet on match results FifApex . And again, the website is build with Oracle Application Express. New this year: I created a mobile version of FifApex ( m.fifapex.net ) with APEX and the jQuery Mobile framework. If you want to know how I’ve done this, come visit my presentation at the ODTUG KScope12 conference in San Antonio, Texas , end of this month. Meanwhile, register for FifApex, enter our predictions, and maybe you will be one of the winners of the prizes …     BTW: if you missed the first games: you still can enter the competition AND, from my experience, I can tell you: there is not a lot football/soccer knowledge required for a good ranking ;-).

This article describes a solution to determine the client device category (i.e. desktop, browser or tablet) your APEX application is accessed from. Until recently, building a web application with Oracle Application Express usually meant to build a desktop browser application. But if you look at the growing number of mobile devices, this will change very soon, if not already has for some of you. Being able to develop applications, that can be accessed by tablets or smart phones offers lots of new possibilities. But it also comes with some challenges. Mobile devices are different. Interaction by touch screen, screen size and (non-) support of certain common web functionality (flash, for example), just to mention a few. Oracles announcement to integrate the jQuery mobile framework into APEX 4.2 will help us to deal with many of the challenges, developing for multiple devices will bring. Until now, one of the biggest challenges is, to determine the actual client your application ...

Yesterdays OGh APEX day in Zeist (NL) was a great success. The probably largest APEX-only congress (almost 300 APEX enthusiasts) was packed with 3 parallel tracks of presentations covering a wide variety of APEX related subjects. The OGh organization committee again managed to invite well known APEX experts as speakers: Dimitri Gielis and John Scott (the dynamic APEX Evangelists Duo), Roel Hartman, Alex Nuijten, Patrick Barel (all ACE or ACED so far). Iloon Ellen Wolff, from Oracle NL, gave us some previews on Oracle’s Cloud Service, mostly slides and video’s. A live demo wasn’t possible, because there is something going on at Oracle and we may can expect some exciting news very soon. The highlight, in my eyes, was Patrick Wolf’s keynote presentation, talking about the recent enhancements of 4.1.1,and, much more exciting, giving us a glimpse of what will come in the long awaited 4.2 upgrade. After showing the usual “Oracle Save Harbor Statement” the conference participants wer...

This short article is actually a shameless plug for my new service and website. So, if you are looking for some technical info on APEX: do not read any further. But if you want to provide your APEX application with a custom UI design without having to dive into HTML, CSS scripting and creating graphical components yourself, pay a visit to my brand new website: themes4apex.com. Define I offer to design and implement APEX themes and templates based on your specifications, whatever these are: an existing web page, concepts created in PowerPoint  or any other image reference or prototyping tool. Design I like to keep things simple. So your custom APEX UI design will be based on HTML and CSS, DIV-based and guaranteed to tested and working in all current browser brands and versions. Deliver You will receive your custom theme ready to import into your APEX environment together with a demo application using the theme. Interested? Visit themes4apex and contact me. ...