/form lifecycle

• Resolve
  • Create FormInstance
  • Initialize FormInstance input fields from URL parameters
• Create Svelte component (Form)
• Initialize Svelte component (Form)
  • If postOnLoad == true and all required inputs have values, post the form
  • Select response handler and handle the response

Default response handler (FormComponentResponseHandler)

FormComponentResponseHandler is the default response handler. It will

1. set FormInstance output fields
2. render output fields

FormInstance

FormInstance provides API to communicate with the server-side form.

Events

• form:posting - just before form is posted to the server (fired by FormInstance). Uses FormEventArgs for event arguments.
• form:responseReceived - fired when response from the server is received, but hasn't been processed yet (fired by FormInstance). Uses FormEventArgs for event arguments.
• form:responseHandled - fired after response from the server has been handled (fired by FormInstance). Uses FormEventArgs for event arguments.

Form.html

Form is a UI control which can render a form in a browser. Form uses FormInstance to facilitate communication with the server and to ensure form lifecycle.

parent

Components are assembled into a hierarchy. Form components can be nested using InlineForm output field. The nested form can access its parent form via Form.parent.

Custom events with fireAndBubbleUp

Each input or output field can publish events up to its Form component and to all parent forms using Form.fireAndBubbleUp.

Built-in events

Form has several built in-events:

• form:loaded - fired as soon as the form has been rendered and initialized (before the initial post-on-load). arguments.
• form:responseHandled - fired after response from the server has been handled.

inputs

Array of input components (i.e. - Svelte components like Textarea.html) which were instantiated for this form.

Input.html

Each input component gets initialized with the these properties:

• field - InputFieldValue instance
• tabindex - auto-calculated tabindex
• id - auto-generated unique identifier
• app - UmfApp instance
• form - parent Form.html
• wrapper - instance of Input.html which wraps the actual input component.

Output.html

Each input component gets initialized with the these properties:

• field - InputFieldValue instance
• app - UmfApp instance
• form - FormInstance object
• parent - instance of Form.html component inside which the output is rendered