Takeaway From This Article

In this article, you’ll learn what StateFlow is, how to use it, the advantages of using it, and the explanation of some real-time problems, with solutions. By comparing it to the LiveData, I’ll post my thoughts about the use of StateFlow over the use of LiveData.

Introduction

Flow API in Coroutines is a better way to handle the stream of data; StateFlow attempts to bring the powerful features of Flow to manage a state in your application. If you see the syntax of StateFlow, it’s extended by SharedFlow. Have a look:

@ExperimentalCoroutinesApi interface StateFlow<out T> : 
    SharedFlow<T> (source)

A SharedFlow is a read-only state with a single updatable data value that emits updates to its collectors. A state flow is a hot flow, unlike the regular flow, because its active instance exists independently of collectors’ presence. The current value of StateFlow can be retrieved through value property.

StateFlow comes in two variants — StateFlow and MutabaleStateFlow.

• StateFlow<T> interface is a read-only view that gives access to the current value and implements a Flow<T> to collect updates to the values.
• MutabaleStateFlow<T> interface adds a value-modification operation.

How to Use StateFlow

First, let’s create an enum class and include a few states that we need to manage in the view when triggered by viewModel. Have a look at the enum class:

enum class CustomStates{
    SHOW_LOADING, HIDE_lOADING, SHOW_TOAST, HOMESCREEN, BACK
}

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