Oracle Visual Builder: Applications That Outlive Their First Release · Module 4 · Variables, types and where state lives
The scopes, and what each one means
Lesson 34 of 176 · 3 min · Free preview
PAGE, FLOW and APPLICATION. How long each LIVES, who can SEE it, and what happens to it when the user NAVIGATES OR REFRESHES. Three scopes, and the difference between them is the single most consequential choice in this module. PAGE SCOPE LIVES AS LONG AS THE PAGE IS OPEN AND NOBODY ELSE CAN SEE IT. Navigate away and it is gone; come back and it starts fresh. That is the right default for almost everything — what is in this field, what this page loaded, which row is selected here. FLOW SCOPE LIVES AS LONG AS THE USER IS INSIDE THE FLOW AND EVERY PAGE IN THAT FLOW CAN SEE IT. Move between pages of the same flow and it survives; leave the flow and it is gone. Which is exactly the shape of "the thing the user is currently working on" — the customer they selected, the order they…
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Watch the full lessonIn this module: Module 4 · Variables, types and where state lives
- 1What a variable is here
- 2The scopes, and what each one meansFree preview
- 3Choosing a scope, deliberately
- 4Types, and why you should declare them
- 5Types that mirror a service
- 6Computed values and expressions
- 7Variables that persist
- 8The event that fires when state changes
- 9State that four pages need
- 10Naming state so it is findable
- 11What breaks: four state failures
- 12Lab briefing · Move state and watch it break