diff --git a/README.md b/README.md
index ee375e2..64c6663 100644
--- a/README.md
+++ b/README.md
@@ -175,18 +175,18 @@ class MainActivity : AppCompatActivity() {
                     }.show()
             }
 
-            override fun onCanceledByUser() {
+            override fun onCanceledByUser(requestCode: Int) {
                 Toast.makeText(baseContext, "Canceled by user", Toast.LENGTH_SHORT).show()
             }
 
-            override fun onStoragePermissionDenied() {
+            override fun onStoragePermissionDenied(requestCode: Int) {
                 /*
                 Request runtime permissions for Manifest.permission.WRITE_EXTERNAL_STORAGE
                 and Manifest.permission.READ_EXTERNAL_STORAGE
                 */
             }
 
-            override fun onRootPathPermissionGranted(root: DocumentFile) {
+            override fun onRootPathPermissionGranted(requestCode: Int, root: DocumentFile) {
                 Toast.makeText(baseContext, "Storage access has been granted for ${root.getStorageId(baseContext)}", Toast.LENGTH_SHORT).show()
             }
         }
@@ -336,7 +336,7 @@ val folder: DocumentFile = ...
 val targetFolder: DocumentFile = ...
 
 // Since moveFolderTo() is annotated with @WorkerThread, you must execute it in background thread
-folder.moveFolderTo(applicationContext, targetFolder, skipEmptyFiles = false, callback = object : FolderCallback {
+folder.moveFolderTo(applicationContext, targetFolder, skipEmptyFiles = false, callback = object : FolderCallback() {
     override fun onPrepare() {
         // Show notification or progress bar dialog with indeterminate state
     }
@@ -345,7 +345,7 @@ folder.moveFolderTo(applicationContext, targetFolder, skipEmptyFiles = false, ca
         // Inform user that the app is counting & calculating files
     }
 
-    override fun onStart(folder: DocumentFile, totalFilesToCopy: Int): Long {
+    override fun onStart(folder: DocumentFile, totalFilesToCopy: Int, workerThread: Thread): Long {
         return 1000 // update progress every 1 second
     }
 
@@ -361,16 +361,16 @@ folder.moveFolderTo(applicationContext, targetFolder, skipEmptyFiles = false, ca
         handleFolderContentConflict(action, conflictedFiles)
     }
 
-    override fun onReport(progress: Float, bytesMoved: Long, writeSpeed: Int, fileCount: Int) {
-        Timber.d("onReport() -> ${progress.toInt()}% | Moved $fileCount files")
+    override fun onReport(report: Report) {
+        Timber.d("onReport() -> ${report.progress.toInt()}% | Copied ${report.fileCount} files")
     }
 
-    override fun onCompleted(folder: DocumentFile, totalFilesToCopy: Int, totalCopiedFiles: Int, success: Boolean) {
-        Timber.d("Moved $totalCopiedFiles of $totalFilesToCopy files")
+    override fun onCompleted(result: Result) {
+        Toast.makeText(baseContext, "Copied ${result.totalCopiedFiles} of ${result.totalFilesToCopy} files", Toast.LENGTH_SHORT).show()
     }
 
-    override fun onFailed(errorCode: FolderCallback.ErrorCode) {
-        Timber.d("An error has occurred: $errorCode")
+    override fun onFailed(errorCode: ErrorCode) {
+        Toast.makeText(baseContext, "An error has occurred: $errorCode", Toast.LENGTH_SHORT).show()
     }
 })
 ```
diff --git a/gradle.properties b/gradle.properties
index 3bffcb9..ad71ea7 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -19,4 +19,4 @@ android.useAndroidX=true
 android.enableJetifier=true
 # Kotlin code style for this project: "official" or "obsolete":
 kotlin.code.style=official
-STORAGE_VERSION=0.8.0-SNAPSHOT
\ No newline at end of file
+STORAGE_VERSION=0.8.0
\ No newline at end of file
diff --git a/storage/src/main/java/com/anggrayudi/storage/SimpleStorage.kt b/storage/src/main/java/com/anggrayudi/storage/SimpleStorage.kt
index 588ac13..099eb6e 100644
--- a/storage/src/main/java/com/anggrayudi/storage/SimpleStorage.kt
+++ b/storage/src/main/java/com/anggrayudi/storage/SimpleStorage.kt
@@ -156,7 +156,7 @@ class SimpleStorage private constructor(private val wrapper: ComponentWrapper) {
             requestCodeStorageAccess = requestCode
             expectedStorageTypeForAccessRequest = expectedStorageType
         } else {
-            storageAccessCallback?.onActivityHandlerNotFound(intent)
+            storageAccessCallback?.onActivityHandlerNotFound(requestCode, intent)
         }
     }
 
@@ -182,7 +182,7 @@ class SimpleStorage private constructor(private val wrapper: ComponentWrapper) {
                 externalStorageRootAccessIntent
             }
             if (!wrapper.startActivityForResult(intent, requestCode))
-                folderPickerCallback?.onActivityHandlerNotFound(intent)
+                folderPickerCallback?.onActivityHandlerNotFound(requestCode, intent)
         } else {
             folderPickerCallback?.onStoragePermissionDenied(requestCode)
         }
@@ -200,7 +200,7 @@ class SimpleStorage private constructor(private val wrapper: ComponentWrapper) {
                 intent.type = filterMimeTypes.firstOrNull() ?: MimeType.UNKNOWN
             }
             if (!wrapper.startActivityForResult(intent, requestCode))
-                filePickerCallback?.onActivityHandlerNotFound(intent)
+                filePickerCallback?.onActivityHandlerNotFound(requestCode, intent)
         } else {
             filePickerCallback?.onStoragePermissionDenied(requestCode, null)
         }
@@ -254,7 +254,7 @@ class SimpleStorage private constructor(private val wrapper: ComponentWrapper) {
                     @Suppress("DEPRECATION")
                     sm.storageVolumes.firstOrNull { it.isRemovable }?.createAccessIntent(null)?.let {
                         if (!wrapper.startActivityForResult(it, requestCode)) {
-                            storageAccessCallback?.onActivityHandlerNotFound(it)
+                            storageAccessCallback?.onActivityHandlerNotFound(requestCode, it)
                         }
                         return
                     }
diff --git a/storage/src/main/java/com/anggrayudi/storage/SimpleStorageHelper.kt b/storage/src/main/java/com/anggrayudi/storage/SimpleStorageHelper.kt
index 0cecbf7..4a6575a 100644
--- a/storage/src/main/java/com/anggrayudi/storage/SimpleStorageHelper.kt
+++ b/storage/src/main/java/com/anggrayudi/storage/SimpleStorageHelper.kt
@@ -116,7 +116,7 @@ class SimpleStorageHelper {
                 reset()
             }
 
-            override fun onActivityHandlerNotFound(intent: Intent) {
+            override fun onActivityHandlerNotFound(requestCode: Int, intent: Intent) {
                 handleMissingActivityHandler()
             }
         }
@@ -149,7 +149,7 @@ class SimpleStorageHelper {
                 reset()
             }
 
-            override fun onActivityHandlerNotFound(intent: Intent) {
+            override fun onActivityHandlerNotFound(requestCode: Int, intent: Intent) {
                 handleMissingActivityHandler()
             }
         }
@@ -168,7 +168,7 @@ class SimpleStorageHelper {
                 reset()
             }
 
-            override fun onActivityHandlerNotFound(intent: Intent) {
+            override fun onActivityHandlerNotFound(requestCode: Int, intent: Intent) {
                 handleMissingActivityHandler()
             }
         }
diff --git a/storage/src/main/java/com/anggrayudi/storage/callback/FilePickerCallback.kt b/storage/src/main/java/com/anggrayudi/storage/callback/FilePickerCallback.kt
index bb1bed9..ea3cc13 100644
--- a/storage/src/main/java/com/anggrayudi/storage/callback/FilePickerCallback.kt
+++ b/storage/src/main/java/com/anggrayudi/storage/callback/FilePickerCallback.kt
@@ -13,7 +13,7 @@ interface FilePickerCallback {
         // default implementation
     }
 
-    fun onActivityHandlerNotFound(intent: Intent) {
+    fun onActivityHandlerNotFound(requestCode: Int, intent: Intent) {
         // default implementation
     }
 
diff --git a/storage/src/main/java/com/anggrayudi/storage/callback/FolderPickerCallback.kt b/storage/src/main/java/com/anggrayudi/storage/callback/FolderPickerCallback.kt
index 8522a29..fd81cd5 100644
--- a/storage/src/main/java/com/anggrayudi/storage/callback/FolderPickerCallback.kt
+++ b/storage/src/main/java/com/anggrayudi/storage/callback/FolderPickerCallback.kt
@@ -15,7 +15,7 @@ interface FolderPickerCallback {
         // default implementation
     }
 
-    fun onActivityHandlerNotFound(intent: Intent) {
+    fun onActivityHandlerNotFound(requestCode: Int, intent: Intent) {
         // default implementation
     }
 
diff --git a/storage/src/main/java/com/anggrayudi/storage/callback/StorageAccessCallback.kt b/storage/src/main/java/com/anggrayudi/storage/callback/StorageAccessCallback.kt
index 2d47184..0200c67 100644
--- a/storage/src/main/java/com/anggrayudi/storage/callback/StorageAccessCallback.kt
+++ b/storage/src/main/java/com/anggrayudi/storage/callback/StorageAccessCallback.kt
@@ -15,7 +15,7 @@ interface StorageAccessCallback {
         // default implementation
     }
 
-    fun onActivityHandlerNotFound(intent: Intent) {
+    fun onActivityHandlerNotFound(requestCode: Int, intent: Intent) {
         // default implementation
     }