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View Full Version : Newbie How-to: Remember main Lianja visual parts



josipradnik
2014-10-17, 06:52
806

barrymavin
2014-10-17, 07:36
Hi Josip,

Good job. Thanks for taking the time.

I refer to all of these "Visual parts" as "UI Elements".

Clearly there are many and in an App you can hide/show them by toggling their attributes in the attributes dialogs for page, section, field or gadget.

Additionally the visual appearance of an App that a particular user sees and can interact (at runtime) with is governed by the "Roles and Permissions" that are granted to a user. In v1.2.4 these roles and permissions can be dynamic and assigned when you add a new user to the system. These roles and permissions enable/disable what CRUD operations (Create, Read, Update, Delete) are in effect in a UI Element I.e. App, Page, Section, Formitem (Field or Gadget).

In the attributes dialogs you also have UI Presentation Rules which provide the ability to hide/show UI Elements depending on the current "Data View" that is being displayed. All of the UI e.g sections can be hidden or shown deoending on the data that is currently being viewed. For example, If a field in a form section has two choices "Single or Married" and "Single" is displayed then a section for "Spouse Information" can be hidden. This is the built-in dynamic nature of the Lianja UI which I refer to as ART (Actions, Rules and Transitions). This provides a very high level of abstraction for building Apps.

The UI States Editor is also instrumental in dynamically altering the UI. This is another place where "Inline Delegates" come into play when they can "changestate" to a known state when certain actions occur. This allows you to further separate what occurs when an "Action" occurs and what "Transition" will then result from this "Action".

Getting to know the attributes for the UI Elements is very important as it will save a lot of development time and therefore a lot of ongoing maintenance time too.

As you pointed out in a previous forum post you can re-arrange Formitems in a Form section by dragging them around. This is also the case with sections. These too can be re-arranged in a page by dragging a section header onto another section header.

Similarly grid columns in Grid sections can be dragged around inside the grid to re-arrange them.

If you look at the system menu by clicking on the icon in the HeaderBar and select "View" you can hide/show various other UI Elements while developing an App.