Tuesday, May 23, 2017

Using CSS Frameworks with Fluid

Unlike PeopleTools Classic, which used almost-pixel-perfect layout, Fluid uses CSS for layout. The benefit of this pattern is flexibility. Unlike Classic pages, which only allowed for one layout, Fluid allows us to manipulate layout with CSS. I like CSS, so I see this as a positive. The more content Oracle development delivers in CSS, the more we can configure and transform the user experience. While I may love what I can do with CSS, it isn't the easiest language/technology to use. As a PeopleSoft developer with a significant amount of front-end development experience, I had this thought:

Could PeopleSoft developers avoid learning and writing CSS by using common, modern CSS frameworks to enhance PeopleSoft pages?

As with anything, the answer is, "Yes," but it isn't that easy. Here is the reason: PeopleSoft stylesheets apply style rules to HTML elements. And this makes sense. Review the most common CSS frameworks and you will see that they do the same thing (honestly, I would despise a CSS framework that didn't apply rules to HTML elements, but that is another story). Here is the problem: since both Fluid and and the framework style HTML elements, there are bound to be conflicts, and those conflicts often cause layout and display problems. Normally this would be fine, because selector specificity and order dictate who wins. The real problem is where the two frameworks have different, but related CSS declarations. The solution? A reset stylesheet. A reset Stylesheet will either reset conflicting Fluid CSS properties or conflicting your-favorite-CSS-framework properties. Now we have a solution. But, this solution has a serious problem: the point of using a CSS framework was to avoid writing CSS. After working through all of these conflicts, it is highly possible that you will write more CSS than you would have without the CSS framework. CSS frameworks are highly powerful and have value, but be careful to pick a CSS framework that uses class selectors only; no element selectors.

I have reviewed many CSS frameworks and it is hard to find one that just uses classes, no element styling. Oracle JET is a CSS framework that supports class-only styling. Oracle JET's Alta CSS stylesheets come in two flavors:

  • HTML element selectors
  • Class-only selectors

To incorporate Oracle JET with PeopleSoft Fluid:

  1. Download the latest class-only oj-alta-notag-min.css file (you can download the uncompressed version if you prefer). It is important that you grab the *-notag-*.css version. This is the one that uses class name selectors rather than HTML element selectors.
  2. Create a new Stylesheet definition and paste the contents of the oj-alta-notag CSS file into the new Stylesheet definition.
  3. Use the AddStylesheet PeopleCode function in a Page Activate event to add the new free form stylesheet to a page.
  4. Add Oracle JET class names to fields on your page.

1. Download the latest oj-alta-notag-min.css file

You don't need to "download" the file, just access its content. We will copy and paste the content into PeopleSoft in the next step. The file is available in raw form on GitHub here.

2. Create a new Stylesheet definition

After logging into your PeopleSoft development instance as an administrator, navigate to PeopleTools > Portal > Branding > Branding Objects. Switch to the Stylesheet tab and select the Upload Style Sheet Object. This will open a dialog where you can paste the CSS from step 1. Be sure to give the Stylesheet an appropriate name. I chose ORACLEJET_FF. Uploading a Stylesheet in this manner creates a managed Stylesheet definition that is accessible from Application Designer, and mixed with all of the other App Designer Stylesheet search results, so naming is important. Be sure to use your site-specific prefix. PeopleTools best practice recommends using the _FF suffix as well to denote this Stylesheet as a Free Form Stylesheet, which differs from the more traditional structured PeopleTools Stylesheet.

3. Use the AddStylesheet PeopleCode function in a Page Activate event

To any page that will use Oracle JET styling, open the PageActivate event and add PeopleCode that looks something like:

AddStyleSheet(StyleSheet.ORACLEJET_FF);

4. Add Oracle JET class names to fields on your page

Now open your Fluid page in Application Designer and identify the field that is supposed to use an Oracle JET class. Open the field's properties and switch to the Fluid tab. In the Fluid tab, set the Default Style Name to an Oracle JET style class. My favorite Oracle style classes to use with Fluid are oj-flex and oj-flex-item because they allow me to use CSS Flex Layout with Groupbox containers to ensure proper responsive design across a variety of form factors.

I think it is safe to say the most popular CSS framework in the world is Bootstrap. A common question developers ask me is, "Can I use Bootstrap with PeopleSoft Fluid?" The answer, of course is, "Yes." While I prefer Oracle JET because of its no-tag alternative, I have friends that successfully use Bootstrap with PeopleSoft Fluid pages. With PeopleSoft, all things are possible!