Skip to main content

Changing appearances.

Lately I've been working on an application that can serve offices in different countries. So what I hear you say.........I do that every day.............use the 'locale.language', use a bundle and be happy ;-) Ok, I know that, but I want to have changing appearances, not only changing text. That can also be done by using a skin selector for instance like the one below:

<skin-family>#{facesContext.viewRoot.locale.language=='de' ? 'german' :

You can use this in the same way as I did in one of my previous posts.

However, I want the application to behave in a way that not the whole look and feel changes, but that only some country specific elements automatically change. I will not go in to the details of the application, but I will try to explain the concept, based on license plates. Imagine a car rental company with cars and offices in different countries.

Whatever country (or even state for that matter) you are in, the license plates are different. Yellow with black numbers, white with red numbers and so on and so on.....

If you have an application in which you show license plates, you can do that by using a 'plain' outputtext field in a table column. This will show the license of the car as plain text.

For me that just doesn't 'feel' right. It would be much nicer if you could add some features that enable you to recognize the country by just looking at the licenseplate.

Wow........... I want that, how can I do that ?

There are several problems here. First one is that licenses have different colors for the background color, the text color and the borders. The dutch plate has a yellow background background-color:rgb(255,255,0);

and a belgian plate has red text color:Red;

You can achieve this by using the styleClass attribute.
<af:column sortable="false" headerText="License">

You can define the style in a css like this;

border:2px solid black;
text-align: center;
color: black;
height: 20pt;
padding-top: 10pt;
If you define all the necessary styles in a css, according to the standard of a country, the looks of the license plate should be recognizable.

A good reader should have noticed by now that something is missing. The styleClass InputLicensePlateStyleNL is only valid for one specific (the dutch) license. This is the second problem. If you want to have coutry specific look and feel, you need something extra.

You can concatenate a String and EL expression. This will evaluate to a valid value.

Now you can try to take this one step further.
There are license plates that are not country specific, but state specific.

Maybe they even have their own specific background images.

If you really want, you might even try to add county and city to this expression.


In the case of this example you would have InputLicensePlateStyle concatenated with US and CA resulting in InputLicensePlateStyleUSCA. This is defined in the stylesheet.
This styleclass has the appropriate background image, and colors to render a Californian plate, and looks like this:
border:2px solid black;
text-align: center;
color: black;
height: 20pt;
padding-top: 10pt;

This post shows that you can style almost anything, as long as you 'have the looks'. Dynamically building the styleClass is a very powerful (and maybe even hidden ? ) feature. I will use it more often from now on.


Popular posts from this blog

ADF 12.1.3 : Implementing Default Table Filter Values

In one of my projects I ran into a requirement where the end user needs to be presented with default values in the table filters. This sounds like it is a common requirement, which is easy to implement. However it proved to be not so common, as it is not in the documentation nor are there any Blogpost to be found that talk about this feature. In this blogpost I describe how to implement this.

The Use Case Explained
Users of the application would typically enter today's date in a table filter in order to get all data that is valid for today. They do this each and every time. In order to facilitate them I want to have the table filter pre-filled with today's date (at the moment of writing July 31st 2015).

So whenever the page is displayed, it should display 'today' in the table filter and execute the query accordingly. The problem is to get the value in the filter without the user typing it. Lets first take a look at how the ADF Search and Filters are implemented by the f…

ADF 11g Quicky 3 : Adding Error, Info and Warning messages

How can we add a message programatically ? Last week I got this question for the second time in a months time. I decided to write a short blogpost on how this works.

Adding messages is very easy, you just need to know how it works.
You can add a message to your faces context by creating a new FacesMessage. Set the severity (ERROR, WARNING, INFO or FATAL ), set the message text, and if nessecary a message detail. The fragment below shows the code for an ERROR message.

1: public void setMessagesErr(ActionEvent actionEvent) {
2: String msg = "This is a message";
3: AdfFacesContext adfFacesContext = null;
4: adfFacesContext = AdfFacesContext.getCurrentInstance();
5: FacesContext ctx = FacesContext.getCurrentInstance();
6: FacesMessage fm =
7: new FacesMessage(FacesMessage.SEVERITY_ERROR, msg, "");
8: ctx.addMessage(null, fm);
9: }

I created a simple page with a couple of buttons to show the result of setting the message. When the butto…

How to: Adding Speech to Oracle Digital Assistant; Talk to me Goose

At Oracle Code One in October, and also on DOAG in Nurnberg Germany in November I presented on how to go beyond your regular chatbot. This presentation contained a part on exposing your Oracle Digital Assistant over Alexa and also a part on face recognition. I finally found the time to blog about it. In this blogpost I will share details of the Alexa implementation in this solution.
Typically there are 3 area's of interest which I will explain. Webhook Code to enable communication between Alexa and Oracle Digital AssistantAlexaDigital Assistant (DA) Explaining the Webhook Code The overall setup contains of Alexa, a NodeJS webhook and an Oracle Digital Assistant.
The webhook code will be responsible for receiving and transforming the JSON payload from the Alexa request. The transformed will be sent to a webhook configured on Oracle DA. The DA will send its response back to the webhook, which will transform into a format that can be used by an Alexa device. To code exposes two REST …