Using Flows in Android

In this section, we will start by using flows in Android for asynchronous programming. Flows are ideal for the parts of your application that involve live data updates.

A Flow of data is represented by the kotlinx.coroutines.flow.Flow interface. Flows emit multiple values of the same type one at a time. For example, Flow<String> is a flow that emits string values.

Android Jetpack libraries such as Room, Paging, DataStore, WorkManager, and Jetpack Compose include built-in support for Flow.

The Room database library added support for Flows, starting with version 2.2. This allows you to be notified of changes in the database values by using Flows.

If your Android application uses a Data Access Object (DAO) to display a list of movies, your project can have a DAO such as the following:

@Dao

interface MovieDao {

    @Query("SELECT * FROM movies")

    fun getMovies(): List<Movie>

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