Mastering the Raw Folder in Android Jetpack Compose

Mastering the Raw Folder in Android Jetpack Compose: A Complete Developer’s Guide

Introduction

When building Android apps, developers often need to include external files such as music, video, configuration files, or simple data. Android provides two primary ways to bundle such files: the assets folder and the raw resource directory. While both serve similar purposes, the raw folder offers a distinct advantage — resource ID referencing, which can simplify file access and improve maintainability.

In the world of modern Android development, especially with Jetpack Compose, it’s essential to understand how to manage raw resources properly. This article walks you through everything you need to know about the res/raw folder: its use cases, advantages, creation process, and practical examples in Jetpack Compose. We’ll also see how it compares with the assets folder and when to choose one over the other.

What is the Raw Folder in Android?

The raw folder is a subdirectory under res/ in your Android project structure. It is designed to store raw, uncompiled files that you want to ship with your application — files that are not XML layouts or images, but things like:

• MP3 or WAV audio clips
• MP4 videos
• .json, .txt, or .xml files for configuration or data
• CSV files for offline data usage

Unlike files placed in the assets directory, resources in the raw folder are accessible via resource identifiers (R.raw.filename). This makes it easier to load them using classes like MediaPlayer, InputStream, or other I/O APIs without the need to handle path strings.

Why Use the Raw Folder in Jetpack Compose Apps?

Although Jetpack Compose is UI-centric and doesn't directly deal with resources like traditional XML-based UIs, you still often need to interact with external files in your app. Here’s where the raw folder becomes handy.

Common Use Cases:

Playing Media Files

Store audio clips (e.g., game sounds, background music) and access them via MediaPlayer.create(context, R.raw.music_file).

Loading JSON or Text Files

Include static JSON or TXT files for offline content or configuration data.

Displaying Local HTML Files

Read and display local HTML in WebViews or custom rendering screens.

Parsing Offline Data

Load XML or CSV data to display stats, scores, or settings.

The main benefit is the convenience of using a simple resource ID rather than managing file paths or filenames manually.

Creating the Raw Folder in Android Studio

Android Studio doesn't create the raw folder by default. But adding it is simple and takes less than a minute:

Step-by-Step Guide:

1. Open your Android project in Android Studio.
2. In the Project panel, navigate to app/src/main/res.
3. Right-click the res folder → Choose New > Android Resource Directory.
4. In the Resource type dropdown, select raw.
5. Click OK.

Now, you’ll see a new raw/ directory inside res/. You can drag and drop files into this folder — for example:

• song.mp3
• config.json
• help.txt

Make sure your filenames are lowercase and do not contain spaces, as resource IDs are derived from them.

Accessing Raw Resources in Jetpack Compose

Even though Jetpack Compose is declarative, it still relies on Android APIs for non-UI functionalities. Here’s how you can load raw files using Kotlin and access them inside a Composable.

Reading a Text File from raw folder

@Composable
fun LoadTextFromRaw() {
    val context = LocalContext.current
    val text = remember {
        context.resources.openRawResource(R.raw.sample_text)
            .bufferedReader()
            .use { it.readText() }
    }

    Text(text = text)
}

Playing an Audio File from raw

@Composable
fun PlayAudioButton() {
    val context = LocalContext.current

    Button(onClick = {
        val mediaPlayer = MediaPlayer.create(context, R.raw.sound_clip)
        mediaPlayer.start()
    }) {
        Text("Play Sound")
    }
}

These examples demonstrate how effortlessly you can integrate raw files into your Compose UI, just like any other Android app.

Raw Folder vs Assets Folder: What's the Difference?

Understanding the differences between res/raw and assets/ is key to using the right folder in the right situation.

Feature	res/raw	assets/
Access Method	Via R.raw.filename (resource ID)	Via file name and AssetManager
Directory Type	Resource folder	Asset folder
Supports Subdirectories	No	Yes
Used For	Media, config, JSON, static data	Games, complex directory structures
Compile-Time ID Access	Yes	No

Create a Fun Memory Match Game with Jetpack Compose using raw folder to add sound effect