Logic - Functions vs Actions

Introduction

Even if Functions and Actions are very close, they have each some specificities:

		Functions	Actions
	Usage examples	Compute text of Button, Compute position of UI Component, Compute math operation, …	Create object in database, send email, perform authentication, …
	Executed when	All inputs are resolved (= have a value) or any input changes	The Control Flow input receives a new “pulse” (e.g. an interaction)
	Order of execution is guaranteed	No	Yes
	Can call other functions	Yes	Yes
	Can call other actions	No	Yes

Custom reusable functions & actions

Custom reusable Functions and Actions can be created in a project.

Inputs and Outputs can be added to the Function / Action:

Actions automatically come with Control Flow Inputs and Outputs:

Function and Actions can be tested using play button:

Best practices

When a function or an action becomes complex, try to create smaller functions/actions and call them from a higher level function/action.

It is a good habit to create reusable functions/actions for any logic that is not directly related to User Interface.

Exercise 9 – Reusable function

The goal of this exercise is to create a reusable function which sums 3 numbers and return the result. This exercise is not linked to the Note app and is here for training purpose.

1. Go to Project “Notes”.
2. Open Folder “Logic”.
3. Create a new Function named “Add 3”.
4. Open the new Function and complete it as follow: