Composable to PDF Converter Library

A Kotlin Multiplatform library for converting Jetpack Compose UI into a PDF file, supporting both Android and iOS. The library ensures that composables like LazyColumn are handled properly by using a Column to capture the full content.

Features

• Convert any Jetpack Compose UI into a PDF.
• Supports Android and iOS.
• Automatically adjusts layouts to avoid rendering issues.
• Option to share the generated PDF file.
• Dynamic PDF page width and height (Planned for future work).

Installation

Add the dependency to your build.gradle.kts file:

implementation("io.github.daanidev:pdf-kmp:1.0.2")
implementation("org.jetbrains.kotlinx:kotlinx-datetime:0.4.0")

Usage

Generating a PDF from a Composable

Use the following code inside a composable function to generate a PDF file:

import kotlinx.datetime.Clock
import kotlinx.datetime.TimeZone
import kotlinx.datetime.toLocalDateTime

val scope = rememberCoroutineScope()
val currentTime = Clock.System.now().toLocalDateTime(TimeZone.currentSystemDefault()).time
val fileName = "test_pdf_${currentTime}"

Button(onClick = {
    scope.launch {
        PDFUtil.generatePdf(
            fileName = fileName,
            content = {
                ShowList() // Your composable function
            },
            shareAfterCreation = false // Set to true to share after creation
        )
    }
}) {
    Text("Click me!")
}

Android Setup

For Android, initialize the context inside the onCreate method of your Activity:

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    ActivityContext.initializeActivityContext(this)
}

Additionally, add the following permissions to AndroidManifest.xml to allow storage access:

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

Also, add the following inside your res/xml folder:

<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path
        name="external_files"
        path="." />
    <cache-path
        name="shared_pdfs"
        path="." />
    <files-path
        name="files"
        path="." />
</paths>

And in your AndroidManifest.xml file inside the <application> tag:

<provider
    android:name="androidx.core.content.FileProvider"
    android:authorities="replace with your authority"
    android:exported="false"
    android:grantUriPermissions="true">
    <meta-data
        android:name="android.support.FILE_PROVIDER_PATHS"
        android:resource="@xml/file_paths" />
</provider>

Best Practices

• Avoid LazyColumn: Use Column instead to capture all items properly.
• Ensure Context Initialization: Required on Android to avoid runtime errors.
• Test on Different Devices: Ensure UI elements render properly across various screen sizes.

Future Work

• Support for dynamic PDF page width and height.

License

This project is licensed under the MIT License.

Contributions

Contributions are welcome! Feel free to submit a pull request or report issues.

Contact

Feel free to open an issue if you have found any.