Localize Android Apps with AI

Preparing Android Apps for Continuous Localization (with Demo App Examples)

Now that you’ve seen how PTC automates the translation process, let’s make sure your Android app is ready for it.

This section shows how to structure your project so PTC can detect updates to your strings.xml file and automatically keep your translations up to date.

We’ll start with a simple Jetpack Compose app that uses hardcoded text and turn it into a localizable project with properly organized resources.

Here’s what we’ll cover:

• Move text from Kotlin into strings.xml
• Organize localized resources under res/values-{{lang}}
• Add placeholders and plurals to handle dynamic text and quantities
• See how PTC automatically updates translations for new or modified strings

1. Extract Hardcoded Strings into strings.xml

Start by moving user-facing text from your Jetpack Compose code into a string resource file. This is the foundation of Android localization and lets PTC detect translatable content.

@Composable
fun Greeting(name: String, modifier: Modifier = Modifier) {
    Text(
        text = "Hello $name!", // Hardcoded string
        modifier = modifier
    )
}

@Composable
fun Greeting(name: String, modifier: Modifier = Modifier) {
    Text(
        text = "Hello $name!", // Hardcoded string
        modifier = modifier
    )
}

<resources>
    <string name="hello_text">Hello %1$s!</string>
</resources>

<resources>
    <string name="hello_text">Hello %1$s!</string>
</resources>

import androidx.compose.ui.res.stringResource
import com.example.androidappdemo.R   // adjust if your package name differs

@Composable
fun Greeting(name: String, modifier: Modifier = Modifier) {
    val hello = stringResource(id = R.string.hello_text, name)
    Text(
        text = hello,
        modifier = modifier
    )
}

import androidx.compose.ui.res.stringResource
import com.example.androidappdemo.R   // adjust if your package name differs

@Composable
fun Greeting(name: String, modifier: Modifier = Modifier) {
    val hello = stringResource(id = R.string.hello_text, name)
    Text(
        text = hello,
        modifier = modifier
    )
}

2. Set Up Continuous Localization in PTC

With your strings.xml file in place, you’re ready to set up PTC and create translations.

1. Sign up or log in to PTC.
2. Create a new project. The setup wizard will guide you through describing your project so PTC can generate context-aware translations.
3. Choose how to integrate PTC with your project for continuous localization. You can connect your GitHub, GitLab, or Bitbucket repository, or use the PTC API to integrate localization into your CI/CD pipeline.
4. Configure the file patterns:

• Source file: app/src/main/res/values/strings.xml
• Translation files: app/src/main/res/values-{{lang}}/strings.xml
• File type: Android XML

After you complete the setup, PTC automatically generates new folders with translated files (for example, res/values-fr/strings.xml) and opens a merge request in your repository.

3. Use Placeholders for Dynamic Content

Now that you’ve seen how PTC handles your initial translations, let’s make the app more realistic by adding dynamic strings. These are strings that include changing values—like a user’s name.

<resources>
    <string name="welcome_user">Welcome, %1$s!</string>
    <string name="points_summary">%1$s, you have %2$d points.</string>
</resources>

<resources>
    <string name="welcome_user">Welcome, %1$s!</string>
    <string name="points_summary">%1$s, you have %2$d points.</string>
</resources>

AndroidDemoTheme {
         Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
                    Column(
                        modifier = Modifier
                            .padding(innerPadding)
                            .padding(16.dp)
                    ) {
                        // keep Greeting
                        Greeting(name = "Android")

                        Spacer(modifier = Modifier.height(16.dp))

                        // placeholders demo
                        Header(name = "PTC", points = 42)

                        Spacer(modifier = Modifier.height(16.dp))
                    }


@Composable
fun Header(name: String, points: Int) {
    val welcome = stringResource(R.string.welcome_user, name)
    val summary = stringResource(R.string.points_summary, name, points)

    Column(modifier = Modifier.padding(16.dp)) {
        Text(welcome)
        Text(summary)
    }
}

AndroidDemoTheme {
         Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
                    Column(
                        modifier = Modifier
                            .padding(innerPadding)
                            .padding(16.dp)
                    ) {
                        // keep Greeting
                        Greeting(name = "Android")

                        Spacer(modifier = Modifier.height(16.dp))

                        // placeholders demo
                        Header(name = "PTC", points = 42)

                        Spacer(modifier = Modifier.height(16.dp))
                    }


@Composable
fun Header(name: String, points: Int) {
    val welcome = stringResource(R.string.welcome_user, name)
    val summary = stringResource(R.string.points_summary, name, points)

    Column(modifier = Modifier.padding(16.dp)) {
        Text(welcome)
        Text(summary)
    }
}

Because your project uses continuous localization, PTC will detect these new strings automatically when you commit.

4. Add Plurals for Quantity-Based Strings

Next, let’s handle plural forms — like “1 message” vs. “5 messages.” Android supports this natively, and PTC translates each plural form automatically.

<resources>
    <plurals name="inbox_count">
        <item quantity="one">%d new message</item>
        <item quantity="other">%d new messages</item>
    </plurals>
</resources>

<resources>
    <plurals name="inbox_count">
        <item quantity="one">%d new message</item>
        <item quantity="other">%d new messages</item>
    </plurals>
</resources>

import androidx.compose.ui.res.pluralStringResource

AndroidDemoTheme {
        Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
                    Column(
                        modifier = Modifier
                            .padding(innerPadding)
                            .padding(16.dp)
                    ) {
                        // keep Greeting
                        Greeting(name = "Android")

                        Spacer(modifier = Modifier.height(16.dp))

                        // plurals demo
                        InboxCount(count = 1)
                        InboxCount(count = 5)
                    }


@Composable
fun InboxCount(count: Int) {
    val text = pluralStringResource(R.plurals.inbox_count, count, count)
    Text(text)
}

import androidx.compose.ui.res.pluralStringResource

AndroidDemoTheme {
        Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
                    Column(
                        modifier = Modifier
                            .padding(innerPadding)
                            .padding(16.dp)
                    ) {
                        // keep Greeting
                        Greeting(name = "Android")

                        Spacer(modifier = Modifier.height(16.dp))

                        // plurals demo
                        InboxCount(count = 1)
                        InboxCount(count = 5)
                    }


@Composable
fun InboxCount(count: Int) {
    val text = pluralStringResource(R.plurals.inbox_count, count, count)
    Text(text)
}

When you push these changes, PTC automatically detects and translates the new plural strings.