App Development Concepts for Oracle's Visual Builder Cloud Service

If you are new to app development, or more specifically, visual development, this article introduces some key concepts related to both. Visual Development is also known as Low-Code and/or Rapid Application Development (RAD). Oracle Visual Builder Cloud Service (VBCS) is a low code environment for quickly building and hosting responsive web and mobile apps.

First, let’s talk about what Visual Development is. Visual Development is drag-and-drop, it’s WYSIWYG, its declarative, and it’s fast! Basically, it means the bulk of your app (or all of it) can be created visually, without having to write code, by using designers to layout user interfaces, define data models, and express business logic. Sometimes code is needed but often times the visual design tools can get you very far (or all the way) to a production app in hours rather than weeks or months.

Every (useful) app requires three components. It requires data, business logic, and an user interface. Data refers to the information that is stored and/or retrieved as well the relationships between data elements. Business logic is custom behavior an application exhibits when an action is taken by the user or by the system. User Interface is the part of the application with which the end user directly interacts.

Now that we have a grasp of these basics of an app, let’s discuss some key concepts with regard to visual app development. This next section will define 10 key concepts in each of those key areas, Data, Busines Logic, and User Interface. Let’s start with User Inteface Concepts.

User Interface Concepts

1) UX First

• UX First is a design methodology in which the app developer focuses on the user experience first and foremost, namely how the user interface presents the data and logic to the end user.
• In Visual Development environments, Data and logic are generated as a result of UX design choices.

2)Drag and Drop

• A Visual Design environment contains three primary areas:
• Form
• Component palette
• Property Inspector
• Drag a component from the component palette
• Drop it onto the form where you want it to be displayed
• Set properties of the components to change look and feel

3) Responsive User Interface

• Responsiveness is the ability for an app user interface to change the way it looks depending on the type of device form factor
• Layout and component sizes are automatically managed by the app and change with the form factor
• Specific behavior can be set for each component and form factor

4) Actions

• Actions are events that are captured from user interface and drive a series of behaviors as a result of that event
• For example, when a specified button is pressed

— Read a value from another user interface field and display it in a message “Hello World”

— Send an email

— Create a new business objects

— Run some custom code

Data Concepts

5) Business Objects

• Business Objects (BO) are a set of fields upon which a user can perform a set of CRUD operations
• Custom BOs are stored within the local database in the backend
• External BOs represent an external service, so the data is stored in that service, but you can interact with it within your app

6) CRUD

• Actions that can be taken upon a business object:
• Create to add a new row to a business object
• Read to retrieve a row, set of rows, or the whole dataset from a business object
• Update to change values in an existing row (or set of rows) in a business object
• Delete to remove a row (or set of row) or a whole dataset from a business object

7) Relationships

• Business Objects, i.e. data, can have relationships with one another
• Parent-Child, or Master-Detail, relationships are those in which a BO can “contain” another BO

– Some of the data comes from the parent and some from the child

• Reference BOs are fields that connect to other BO fields

– The data lives in the reference BO

Business Logic

8) Workflow

• Business Logic Workflow is the set of steps a process follows
• A workflow has a begin state, and end state, and several states in between
• A begin state is called a Trigger or Action
• A Trigger is in the data and an Action is in the UI

9) Conditionals and Criteria

• How a workflow moves through states from begin to end is based on conditional logic

– If this, then…

• Criteria specify how the condition is checked

– If field equals true

– If amount is greater than $$$

– If string contains substring

10) The App Lifecycle

• The App Lifecycle is the set of stages that take an app from development, through testing, and finally to production

— dev/test/prod

• To publish an app, move the app through the app lifecycle
• Dev apps are fluid and change a lot
• Test apps are Staged and accessible to others
• Prod apps are Live and cannot be modified by a developer

— a new version must be created