Refactor PdfDownloader to use coroutines and OkHttp's async API

app/build.gradle.kts

@@ -9,7 +9,7 @@ plugins {
 android {
     namespace = "com.rajat.sample.pdfviewer"
 
-    compileSdk = 35
+    compileSdk = 36
 
     defaultConfig {
         applicationId = "com.rajat.sample.pdfviewer"
@@ -29,7 +29,7 @@ android {
     }
 
     kotlin {
-        jvmToolchain(17)
+        jvmToolchain(21)
     }
 
     buildTypes {
@@ -92,30 +92,30 @@ android {
 dependencies {
 
     implementation("com.google.android.material:material:1.12.0")
-    implementation("androidx.test.espresso:espresso-contrib:3.6.1")
-    val kotlin_version = "2.1.20"
+    implementation("androidx.test.espresso:espresso-contrib:3.7.0")
+    val kotlin_version = "2.2.10"
     implementation(kotlin("stdlib"))
     implementation(fileTree(mapOf("dir" to "libs", "include" to listOf("*.jar"))))
     //noinspection GradleDependency
     implementation("org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version")
-    implementation("androidx.core:core-ktx:1.15.0")
-    implementation("androidx.appcompat:appcompat:1.7.0")
+    implementation("androidx.core:core-ktx:1.17.0")
+    implementation("androidx.appcompat:appcompat:1.7.1")
     implementation("androidx.constraintlayout:constraintlayout:2.2.1")
-    implementation("androidx.lifecycle:lifecycle-runtime-ktx:2.8.7")
+    implementation("androidx.lifecycle:lifecycle-runtime-ktx:2.9.2")
     implementation("androidx.compose.ui:ui-graphics")
     testImplementation("junit:junit:4.13.2")
-    androidTestImplementation("androidx.test.ext:junit:1.2.1")
-    androidTestImplementation("androidx.test.espresso:espresso-core:3.6.1")
+    androidTestImplementation("androidx.test.ext:junit:1.3.0")
+    androidTestImplementation("androidx.test.espresso:espresso-core:3.7.0")
     implementation(project(":pdfViewer"))
 //    implementation("io.github.afreakyelf:Pdf-Viewer:2.1.1")
-    testImplementation("androidx.test:core:1.6.1")
-    androidTestImplementation("androidx.test:rules:1.6.1")
-    androidTestImplementation("androidx.test.ext:junit-ktx:1.2.1")
+    testImplementation("androidx.test:core:1.7.0")
+    androidTestImplementation("androidx.test:rules:1.7.0")
+    androidTestImplementation("androidx.test.ext:junit-ktx:1.3.0")
 
     implementation("androidx.recyclerview:recyclerview:1.4.0") // Check for the latest version available
 
     // compose
-    implementation(platform("androidx.compose:compose-bom:2025.03.00"))
+    implementation(platform("androidx.compose:compose-bom:2025.08.00"))
 
     // Choose one of the following:
     // Material Design 3
@@ -130,16 +130,16 @@ dependencies {
 
     // Android Studio Preview support
     implementation("androidx.compose.ui:ui-tooling-preview")
-    androidTestImplementation(platform("androidx.compose:compose-bom:2025.04.01"))
+    androidTestImplementation(platform("androidx.compose:compose-bom:2025.08.00"))
     debugImplementation("androidx.compose.ui:ui-tooling")
 
     // UI Tests
     androidTestImplementation("androidx.compose.ui:ui-test-junit4")
     debugImplementation("androidx.compose.ui:ui-test-manifest")
-    androidTestImplementation("androidx.test.ext:junit:1.2.1")
-    androidTestImplementation("androidx.test.espresso:espresso-core:3.6.1")
-    androidTestImplementation("androidx.test:rules:1.6.1")
-    androidTestImplementation("androidx.test:runner:1.6.1")
+    androidTestImplementation("androidx.test.ext:junit:1.3.0")
+    androidTestImplementation("androidx.test.espresso:espresso-core:3.7.0")
+    androidTestImplementation("androidx.test:rules:1.7.0")
+    androidTestImplementation("androidx.test:runner:1.7.0")
 
 
     // Optional - Integration with activities

build.gradle.kts

@@ -1,7 +1,7 @@
 
 plugins {
-    id("com.android.application") version "8.10.0" apply false
-    id("com.android.library") version "8.10.0" apply false
-    id("org.jetbrains.kotlin.android") version "2.1.20" apply false
-    id("org.jetbrains.kotlin.plugin.compose") version "2.1.20" apply false
+    id("com.android.application") version "8.12.1" apply false
+    id("com.android.library") version "8.12.1" apply false
+    id("org.jetbrains.kotlin.android") version "2.2.10" apply false
+    id("org.jetbrains.kotlin.plugin.compose") version "2.2.10" apply false
 }

gradle/wrapper/gradle-wrapper.properties

@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.11.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.14.3-bin.zip

pdfViewer/build.gradle.kts

@@ -6,13 +6,13 @@ plugins {
     id("org.jetbrains.kotlin.android")
     id("org.jetbrains.kotlin.plugin.compose")
     id("kotlin-parcelize")
-    id("org.jetbrains.dokka") version "1.9.20"
+    id("org.jetbrains.dokka") version "2.0.0"
     id("com.vanniktech.maven.publish") version "0.28.0"
 }
 
 android {
     namespace = "com.rajat.pdfviewer"
-    compileSdk = 35
+    compileSdk = 36
 
     defaultConfig {
         minSdk = 21
@@ -38,7 +38,7 @@ android {
     }
 
     kotlin {
-        jvmToolchain(17)
+        jvmToolchain(21)
     }
 
     buildFeatures {
@@ -49,35 +49,35 @@ android {
 }
 
 dependencies {
-    implementation("androidx.compose.material3:material3-android:1.3.1")
-    val kotlin_version = "2.1.20"
+    implementation("androidx.compose.material3:material3-android:1.3.2")
+    val kotlin_version = "2.2.10"
     implementation(fileTree(mapOf("dir" to "libs", "include" to listOf("*.jar"))))
     implementation("org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version")
-    implementation("androidx.core:core-ktx:1.15.0")
-    implementation("androidx.appcompat:appcompat:1.7.0")
+    implementation("androidx.core:core-ktx:1.17.0")
+    implementation("androidx.appcompat:appcompat:1.7.1")
     implementation("androidx.recyclerview:recyclerview:1.4.0")
-    implementation("androidx.constraintlayout:constraintlayout:2.2.0")
-    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.8.1")
-    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.10.1")
+    implementation("androidx.constraintlayout:constraintlayout:2.2.1")
+    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.10.2")
+    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.10.2")
     implementation("com.google.android.material:material:1.12.0")
     testImplementation("junit:junit:4.13.2")
-    androidTestImplementation("androidx.test.ext:junit:1.2.1")
-    androidTestImplementation("androidx.test.espresso:espresso-core:3.6.1")
+    androidTestImplementation("androidx.test.ext:junit:1.3.0")
+    androidTestImplementation("androidx.test.espresso:espresso-core:3.7.0")
     // ViewModel
-    implementation("androidx.lifecycle:lifecycle-viewmodel-ktx:2.8.7")
-    implementation("androidx.activity:activity-ktx:1.10.0")
+    implementation("androidx.lifecycle:lifecycle-viewmodel-ktx:2.9.2")
+    implementation("androidx.activity:activity-ktx:1.10.1")
     // compose
-    implementation(platform("androidx.compose:compose-bom:2025.04.01"))
-    androidTestImplementation(platform("androidx.compose:compose-bom:2025.04.01"))
+    implementation(platform("androidx.compose:compose-bom:2025.08.00"))
+    androidTestImplementation(platform("androidx.compose:compose-bom:2025.08.00"))
     implementation("androidx.compose.ui:ui")
     // Android Studio Preview support
     implementation("androidx.compose.ui:ui-tooling-preview:")
     debugImplementation("androidx.compose.ui:ui-tooling")
     // UI Tests
     androidTestImplementation("androidx.compose.ui:ui-test-junit4")
     debugImplementation("androidx.compose.ui:ui-test-manifest")
-    implementation("androidx.activity:activity-compose:1.10.0")
-    implementation("com.squareup.okhttp3:okhttp:4.12.0")
+    implementation("androidx.activity:activity-compose:1.10.1")
+    implementation("com.squareup.okhttp3:okhttp:5.1.0")
 }
 
 mavenPublishing {

pdfViewer/src/main/java/com/rajat/pdfviewer/PdfDownloader.kt

@@ -13,13 +13,18 @@ import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.suspendCancellableCoroutine
 import kotlinx.coroutines.withContext
+import okhttp3.Call
+import okhttp3.Callback
 import okhttp3.OkHttpClient
 import okhttp3.Protocol
 import okhttp3.Request
 import okhttp3.Response
 import java.io.File
 import java.io.IOException
+import kotlin.coroutines.resume
+import kotlin.coroutines.resumeWithException
 
 class PdfDownloader(
     private val coroutineScope: CoroutineScope,
@@ -175,13 +180,32 @@ class PdfDownloader(
             }
         }
 
-    private fun makeNetworkRequest(downloadUrl: String): Response {
+    private suspend fun makeNetworkRequest(downloadUrl: String): Response {
         val requestBuilder = Request.Builder().url(downloadUrl)
         headers.headers.forEach { (key, value) -> requestBuilder.addHeader(key, value) }
 
-        return httpClient.newCall(requestBuilder.build()).execute()
+        return httpClient.awaitCall(requestBuilder.build())
     }
 
+    private suspend fun OkHttpClient.awaitCall(request: Request): Response =
+        suspendCancellableCoroutine { cont ->
+            val call = newCall(request)
+
+            cont.invokeOnCancellation {
+                call.cancel()
+            }
+
+            call.enqueue(object : Callback {
+                override fun onFailure(call: Call, e: IOException) {
+                    if (cont.isActive) cont.resumeWithException(e)
+                }
+
+                override fun onResponse(call: Call, response: Response) {
+                    if (cont.isActive) cont.resume(response)
+                }
+            })
+        }
+
     private fun validateResponse(response: Response) {
         if (!response.isSuccessful) {
             throw DownloadFailedException("Failed to download PDF, HTTP Status: ${response.code}")

pdfViewer/src/main/java/com/rajat/pdfviewer/PdfRendererView.kt

@@ -15,9 +15,13 @@ import android.view.LayoutInflater
 import android.view.WindowManager
 import android.widget.FrameLayout
 import android.widget.TextView
+import androidx.fragment.app.Fragment
+import androidx.lifecycle.DefaultLifecycleObserver
 import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.LifecycleCoroutineScope
 import androidx.lifecycle.LifecycleObserver
+import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.lifecycleScope
 import androidx.recyclerview.widget.DefaultItemAnimator
 import androidx.recyclerview.widget.DividerItemDecoration
 import androidx.recyclerview.widget.LinearLayoutManager
@@ -141,6 +145,60 @@ class PdfRendererView @JvmOverloads constructor(
             )).start()
     }
 
+    /**
+     * Initializes the PDF view with a remote URL. Downloads and renders the PDF.
+     *
+     * @param url The URL of the PDF file.
+     * @param headers Optional HTTP headers.
+     * @param lifecycleOwner The LifecycleOwner to bind the download lifecycle.
+     * @param cacheStrategy Cache strategy to apply.
+     */
+    fun initWithUrl(
+        url: String,
+        headers: HeaderData = HeaderData(),
+        lifecycleOwner: LifecycleOwner,
+        cacheStrategy: CacheStrategy = CacheStrategy.MAXIMIZE_PERFORMANCE
+    ) {
+
+        lifecycleOwner.lifecycle.addObserver(object : DefaultLifecycleObserver {
+            override fun onCreate(owner: LifecycleOwner) {
+                super.onCreate(owner)
+                val lifecycleScope = lifecycleOwner.lifecycleScope
+                [email protected] = cacheStrategy
+                PdfDownloader(
+                    lifecycleScope,
+                    headers,
+                    url,
+                    cacheStrategy,
+                    PdfDownloadCallback(
+                        context,
+                        onStart = {
+                            statusListener?.onPdfLoadStart()
+                        },
+                        onProgress = { progress, current, total ->
+                            statusListener?.onPdfLoadProgress(progress, current, total)
+                        },
+                        onSuccess = {
+                            try {
+                                initWithFile(it, cacheStrategy)
+                                statusListener?.onPdfLoadSuccess(it.absolutePath)
+                            } catch (e: Exception) {
+                                statusListener?.onError(e)
+                            }
+                        },
+                        onError = {
+                            statusListener?.onError(it)
+                        }
+                    )).start()
+            }
+
+            override fun onDestroy(owner: LifecycleOwner) {
+                super.onDestroy(owner)
+                lifecycleOwner.lifecycle.removeObserver(this)
+            }
+        })
+    }
+
     /**
      * Initializes the PDF view with a local [File].
      *

pdfViewer/src/main/java/com/rajat/pdfviewer/util/FileUtils.kt

@@ -11,6 +11,8 @@ import android.os.ParcelFileDescriptor
 import android.provider.MediaStore
 import android.util.Log
 import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.coroutineScope
+import kotlinx.coroutines.ensureActive
 import kotlinx.coroutines.withContext
 import java.io.*
 
@@ -73,23 +75,25 @@ object FileUtils {
             ?.forEach { it.delete() }
     }
 
-    fun writeFile(inputStream: InputStream, file: File, totalLength: Long, onProgress: (Long) -> Unit) {
-        FileOutputStream(file).use { outputStream ->
-            val data = ByteArray(8192)
-            var totalBytesRead = 0L
-            var bytesRead: Int
-            while (inputStream.read(data).also { bytesRead = it } != -1) {
-                outputStream.write(data, 0, bytesRead)
-                totalBytesRead += bytesRead
-                try {
-                    onProgress(totalBytesRead)
-                } catch (e: Exception) {
-                    Log.w(TAG, "Progress callback failed: ${e.message}", e)
+    suspend fun writeFile(inputStream: InputStream, file: File, totalLength: Long, onProgress: (Long) -> Unit) =
+        coroutineScope {
+            FileOutputStream(file).use { outputStream ->
+                val data = ByteArray(8192)
+                var totalBytesRead = 0L
+                var bytesRead: Int
+                while (inputStream.read(data).also { bytesRead = it } != -1) {
+                    ensureActive()
+                    outputStream.write(data, 0, bytesRead)
+                    totalBytesRead += bytesRead
+                    try {
+                        onProgress(totalBytesRead)
+                    } catch (e: Exception) {
+                        Log.w(TAG, "Progress callback failed: ${e.message}", e)
+                    }
                 }
+                outputStream.flush()
             }
-            outputStream.flush()
         }
-    }
 
     suspend fun isValidPdf(file: File?): Boolean = withContext(Dispatchers.IO) {
         if (file == null || !file.exists() || file.length() < 4) {