Mobile forms component enables XFA forms on mobile devices. The same XFA form that can be used for generating pdf, can be used to generate html form as well. The html version should behave almost exactly same as the pdf version. XFA has a very rich support for scripting. It supports tons of APIs and almost all the properties are exposed via scripting interface. But as the famous 80-20 rule suggests our customers use only 20 % of that capability. The difficult part was to find those script constructs that are used in real world cases and prioritize them higher than the rest of the script constructs. We have run through the large collection of customer XDPs we have and generated the list of javascript constructs that people use. Interestingly, we found that usage to be less than 20%. Out of 2600 javascript object properties and APIs, forms were using around 200 constructs at least once. So we decided to prioritize based on it. Mobile Form is covering that gap fast but there would be certain things that would never make sense in html or mobile world.
Here is screenshot of both pdf as well as html form for comparison.
Then there are things that matters in pdf world doesn’t have same importance in html/mobile world, e.x. barcodes. Barcodes are more relevant in printed documents so we decided to do away with this barcode object purely from UI level. We still keep it at model level so one can always generate pdf with barcode using the data exported from the html form. If required, one can always insert custom widgets to show barcodes on html form. That is the beauty of Mobile Form architecture. It is way more open than the pdf form where all the widgets are locked down. In Mobile Forms world, one can customize the widgets to enhance the user experience on Mobile devices. For example, one can replace the xfa numeric field with the slider object to capture number information from users.
Signature field is another component that can be interestingly done using the html world solutions like e-sign. So we decided to de-prioritize it for Mobile Forms. On the other hand, we provide a scribble object, using that one can scribble his signature on the form and it will be saved as an image on the form. More detail on the scribble form can be found here.
As I mentioned, Mobile Form will look like almost same as Pdf form. Time has come to explain the almost part here. Mobile Form, because of its html nature has lot of advantages, for example easier to customize, faster opening time, availability on mobile etc. But it has its own set of inherent issues also like support for very thin lines thinner than 1 px.
We use data uri scheme to show images in the Mobile Form. This is supported by all the modern versions of the browsers but you cannot help but notice the differences in the range of image formats that these browsers support. So one should test the images across all the browser matrix before deploying the forms.
In mobile form, pagination, the ability to generate pages due to content changes like adding enough text in the text box to go beyond page boundaries, doesn’t matter. But keeping all the content cluttered would not look nice either. Mobile Form, that is why, chooses a hybrid approach where it generates panels, a box to give feel of pages, as many as there is in the template but it doesn’t increase or reduce panels by data content merged or by user content.
