a) Directory changed from app specific to public now its sharable. b) Library androidx document addition c) this resolve issue file deleting after uninstall the app d) this also resolve bug related to zim file not able to load from app specific folder in android 10 and above.

app/src/main/java/org/kiwix/kiwixmobile/nav/destination/library/OnlineLibraryFragment.kt

@@ -18,6 +18,8 @@
 
 package org.kiwix.kiwixmobile.nav.destination.library
 
+import android.annotation.SuppressLint
+import android.app.Activity
 import android.content.Intent
 import android.net.ConnectivityManager
 import android.os.Bundle
@@ -31,6 +33,7 @@ import android.view.ViewGroup
 import androidx.appcompat.app.AppCompatActivity
 import androidx.appcompat.widget.SearchView
 import androidx.appcompat.widget.Toolbar
+import androidx.documentfile.provider.DocumentFile
 import androidx.lifecycle.Observer
 import androidx.lifecycle.ViewModelProvider
 import androidx.recyclerview.widget.LinearLayoutManager
@@ -53,7 +56,10 @@ import org.kiwix.kiwixmobile.core.extensions.closeKeyboard
 import org.kiwix.kiwixmobile.core.extensions.snack
 import org.kiwix.kiwixmobile.core.main.CoreMainActivity
 import org.kiwix.kiwixmobile.core.utils.BookUtils
+import org.kiwix.kiwixmobile.core.utils.EXTERNAL_SELECT_POSITION
+import org.kiwix.kiwixmobile.core.utils.INTERNAL_SELECT_POSITION
 import org.kiwix.kiwixmobile.core.utils.NetworkUtils
+import org.kiwix.kiwixmobile.core.utils.REQUEST_SELECT_FOLDER_PERMISSION
 import org.kiwix.kiwixmobile.core.utils.SharedPreferenceUtil
 import org.kiwix.kiwixmobile.core.utils.SimpleRecyclerViewScrollListener
 import org.kiwix.kiwixmobile.core.utils.SimpleTextListener
@@ -66,6 +72,7 @@ import org.kiwix.kiwixmobile.zim_manager.library_view.AvailableSpaceCalculator
 import org.kiwix.kiwixmobile.zim_manager.library_view.adapter.LibraryAdapter
 import org.kiwix.kiwixmobile.zim_manager.library_view.adapter.LibraryDelegate
 import org.kiwix.kiwixmobile.zim_manager.library_view.adapter.LibraryListItem
+import java.io.File
 import javax.inject.Inject
 
 class OnlineLibraryFragment : BaseFragment(), FragmentActivityExtensions {
@@ -243,7 +250,52 @@ class OnlineLibraryFragment : BaseFragment(), FragmentActivityExtensions {
   }
 
   private fun storeDeviceInPreferences(storageDevice: StorageDevice) {
-    sharedPreferenceUtil.putPrefStorage(storageDevice.name)
+    if (storageDevice.isInternal) {
+      sharedPreferenceUtil.putPrefStorage(
+        sharedPreferenceUtil.getActualPath(storageDevice.name)
+      )
+      sharedPreferenceUtil.putStoragePosition(INTERNAL_SELECT_POSITION)
+    } else {
+      setFolder()
+    }
+  }
+
+  private fun setFolder() {
+    val intent = Intent(Intent.ACTION_OPEN_DOCUMENT_TREE)
+    intent.putExtra("android.content.extra.SHOW_ADVANCED", true)
+    startActivityForResult(intent, REQUEST_SELECT_FOLDER_PERMISSION)
+  }
+
+  @SuppressLint("WrongConstant") override fun onActivityResult(
+    requestCode: Int,
+    resultCode: Int,
+    data: Intent?
+  ) {
+    super.onActivityResult(requestCode, resultCode, data)
+    if (requestCode == REQUEST_SELECT_FOLDER_PERMISSION && resultCode == Activity.RESULT_OK) {
+      val uri = data!!.data
+      val takeFlags = data.flags and (Intent.FLAG_GRANT_READ_URI_PERMISSION
+        or Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
+      requireActivity().grantUriPermission(
+        requireActivity().packageName, uri,
+        Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_GRANT_WRITE_URI_PERMISSION
+      )
+      requireActivity().contentResolver.takePersistableUriPermission(uri!!, takeFlags)
+      val dfile = DocumentFile.fromTreeUri(requireActivity(), uri)
+      val meraPath = dfile!!.uri.path!!.substring(
+        dfile.uri.path!!.lastIndexOf(":") + 1
+      )
+      var path = "${requireActivity().getExternalFilesDirs("")[1]}"
+      val separator = "/Android"
+      val sepPos = path.indexOf(separator)
+      if (sepPos == -1) {
+      } else {
+        path = path.substring(0, sepPos)
+      }
+      path = path + File.separator + meraPath
+      sharedPreferenceUtil.putPrefStorage(path)
+      sharedPreferenceUtil.putStoragePosition(EXTERNAL_SELECT_POSITION)
+    }
   }
 
   private fun onBookItemClick(item: LibraryListItem.BookItem) {

app/src/main/java/org/kiwix/kiwixmobile/settings/KiwixPrefsFragment.kt

@@ -41,7 +41,7 @@ class KiwixPrefsFragment : CorePrefsFragment() {
 
   override fun setStorage() {
     findPreference<Preference>(PREF_STORAGE)?.title = getString(
-      if (sharedPreferenceUtil.prefStorage == internalStorage()) R.string.internal_storage
+      if (sharedPreferenceUtil.prefStorage == internalStorage()?.let(sharedPreferenceUtil::getActualPath)) R.string.internal_storage
       else R.string.external_storage
     )
     findPreference<Preference>(PREF_STORAGE)?.summary = storageCalculator.calculateAvailableSpace()

buildSrc/src/main/kotlin/Libs.kt

@@ -7,6 +7,14 @@ import kotlin.String
  *   `$ ./gradlew buildSrcVersions`
  */
 object Libs {
+
+  /**
+   * For Getting Path of Selected Folder
+   **/
+
+  const val select_folder_document_file =
+    "androidx.documentfile:documentfile:" + Versions.document_file_version
+
   /**
    * https://github.com/Kotlin/kotlinx.coroutines
    */

buildSrc/src/main/kotlin/Versions.kt

@@ -11,6 +11,9 @@ import org.gradle.plugin.use.PluginDependencySpec
  * YOU are responsible for updating manually the dependency version.
  */
 object Versions {
+
+  const val document_file_version: String = "1.0.1"
+
   const val org_jetbrains_kotlinx_kotlinx_coroutines: String = "1.4.1"
 
   const val androidx_test_espresso: String = "3.3.0"

core/build.gradle.kts

@@ -47,6 +47,9 @@ dependencies {
   implementation(Libs.squidb_annotations)
   add("kapt", Libs.squidb_processor)
 
+  // Document File
+  implementation(Libs.select_folder_document_file)
+
   // Square
   implementation(Libs.converter_simplexml) {
     exclude(group = "xpp3", module = "xpp3")

core/src/main/java/eu/mhutti1/utils/storage/adapter/StorageViewHolder.kt

@@ -43,7 +43,9 @@ internal class StorageViewHolder(
       else R.string.external_storage
     )
 
-    file_name.isChecked = sharedPreferenceUtil.prefStorage == item.name
+    if (adapterPosition == sharedPreferenceUtil.storagePosition) {
+      file_name.isChecked = true
+    }
     file_size.text = storageCalculator.calculateAvailableSpace(item.file) + " / " +
       storageCalculator.calculateTotalSpace(item.file) + "  "
     clickOverlay.setOnClickListener {

core/src/main/java/org/kiwix/kiwixmobile/core/settings/CorePrefsFragment.java

@@ -20,12 +20,17 @@ package org.kiwix.kiwixmobile.core.settings;
 
 import android.Manifest;
 import android.annotation.SuppressLint;
+import android.content.Intent;
 import android.content.SharedPreferences;
 import android.content.pm.PackageManager;
+import android.net.Uri;
 import android.os.Bundle;
+import android.util.Log;
 import android.view.LayoutInflater;
 import android.webkit.WebView;
+import androidx.annotation.Nullable;
 import androidx.core.content.ContextCompat;
+import androidx.documentfile.provider.DocumentFile;
 import androidx.navigation.NavController;
 import androidx.preference.EditTextPreference;
 import androidx.preference.ListPreference;
@@ -51,6 +56,10 @@ import org.kiwix.kiwixmobile.core.utils.SharedPreferenceUtil;
 import org.kiwix.kiwixmobile.core.utils.dialog.DialogShower;
 import org.kiwix.kiwixmobile.core.utils.dialog.KiwixDialog;
 
+import static android.app.Activity.RESULT_OK;
+import static org.kiwix.kiwixmobile.core.utils.ConstantsKt.EXTERNAL_SELECT_POSITION;
+import static org.kiwix.kiwixmobile.core.utils.ConstantsKt.INTERNAL_SELECT_POSITION;
+import static org.kiwix.kiwixmobile.core.utils.ConstantsKt.REQUEST_SELECT_FOLDER_PERMISSION;
 import static org.kiwix.kiwixmobile.core.utils.SharedPreferenceUtil.PREF_NIGHT_MODE;
 import static org.kiwix.kiwixmobile.core.utils.SharedPreferenceUtil.PREF_STORAGE;
 
@@ -175,9 +184,6 @@ public abstract class CorePrefsFragment extends PreferenceFragmentCompat impleme
     versionPref.setSummary(getVersionName() + " Build: " + getVersionCode());
   }
 
-
-
-
   private int getVersionCode() {
     try {
       return getActivity().getPackageManager()
@@ -278,13 +284,52 @@ public abstract class CorePrefsFragment extends PreferenceFragmentCompat impleme
     findPreference(PREF_STORAGE).setSummary(
       storageCalculator.calculateAvailableSpace(storageDevice.getFile())
     );
-    sharedPreferenceUtil.putPrefStorage(storageDevice.getName());
+
     if (storageDevice.isInternal()) {
+      sharedPreferenceUtil.putPrefStorage(
+        sharedPreferenceUtil.getActualPath(storageDevice.getName()));
       findPreference(PREF_STORAGE).setTitle(getString(R.string.internal_storage));
+      sharedPreferenceUtil.putStoragePosition(INTERNAL_SELECT_POSITION);
     } else {
-      findPreference(PREF_STORAGE).setTitle(getString(R.string.external_storage));
+      setFolder();
     }
     return Unit.INSTANCE;
   }
 
+  private void setFolder() {
+    Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT_TREE);
+    intent.putExtra("android.content.extra.SHOW_ADVANCED", true);
+    startActivityForResult(intent, REQUEST_SELECT_FOLDER_PERMISSION);
+  }
+
+  @SuppressLint("WrongConstant") @Override
+  public void onActivityResult(int requestCode, int resultCode,
+    @Nullable Intent data) {
+    super.onActivityResult(requestCode, resultCode, data);
+    if (requestCode == REQUEST_SELECT_FOLDER_PERMISSION && resultCode == RESULT_OK) {
+      Uri uri = data.getData();
+      int takeFlags = data.getFlags() & (Intent.FLAG_GRANT_READ_URI_PERMISSION
+        | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
+      getActivity().grantUriPermission(getActivity().getPackageName(), uri,
+        Intent.FLAG_GRANT_READ_URI_PERMISSION | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
+      getActivity().getContentResolver().takePersistableUriPermission(uri, takeFlags);
+
+      DocumentFile dfile = DocumentFile.fromTreeUri(getActivity(), uri);
+      String meraPath =
+        dfile.getUri().getPath().substring(dfile.getUri().getPath().lastIndexOf(":") + 1);
+
+      String path = getActivity().getExternalFilesDirs("")[1].toString();
+      String separator = "/Android";
+      int sepPos = path.indexOf(separator);
+      if (sepPos == -1) {
+
+      } else {
+        path = path.substring(0, sepPos);
+      }
+      path = path + File.separator + meraPath;
+      sharedPreferenceUtil.putPrefStorage(path);
+      findPreference(PREF_STORAGE).setTitle(getString(R.string.external_storage));
+      sharedPreferenceUtil.putStoragePosition(EXTERNAL_SELECT_POSITION);
+    }
+  }
 }

core/src/main/java/org/kiwix/kiwixmobile/core/utils/Constants.kt

@@ -23,6 +23,7 @@ const val CONTACT_EMAIL_ADDRESS = "android@kiwix.org"
 // Request stuff
 const val REQUEST_STORAGE_PERMISSION = 1
 const val REQUEST_WRITE_STORAGE_PERMISSION_ADD_NOTE = 3
+const val REQUEST_SELECT_FOLDER_PERMISSION = 4
 
 // Tags
 const val TAG_FILE_SEARCHED = "searchedarticle"
@@ -37,3 +38,8 @@ const val TAG_FROM_TAB_SWITCHER = "fromtabswitcher"
 const val EXTRA_IS_WIDGET_VOICE = "isWidgetVoice"
 const val HOTSPOT_SERVICE_CHANNEL_ID = "hotspotService"
 const val OLD_PROVIDER_DOMAIN = "org.kiwix.zim.base"
+
+
+// For Storage select dialog
+const val INTERNAL_SELECT_POSITION = 0
+const val EXTERNAL_SELECT_POSITION = 1

core/src/main/java/org/kiwix/kiwixmobile/core/utils/SharedPreferenceUtil.kt

@@ -76,12 +76,15 @@ class SharedPreferenceUtil @Inject constructor(val context: Context) {
     get() {
       val storage = sharedPreferences.getString(PREF_STORAGE, null)
       return when {
-        storage == null -> defaultStorage().also(::putPrefStorage)
+        storage == null -> getActualPath(defaultStorage()).also(::putPrefStorage)
-        !File(storage).exists() -> defaultStorage()
+        !File(storage).exists() -> getActualPath(defaultStorage())
         else -> storage
       }
     }
 
+  val storagePosition: Int
+    get() = sharedPreferences.getInt(STORAGE_POSITION, 0)
+
   private fun defaultStorage(): String =
     getExternalFilesDirs(context, null)[0]?.path
       ?: context.filesDir.path // a workaround for emulators
@@ -108,6 +111,10 @@ class SharedPreferenceUtil @Inject constructor(val context: Context) {
     _prefStorages.onNext(storage)
   }
 
+  fun putStoragePosition(pos: Int) {
+    sharedPreferences.edit { putInt(STORAGE_POSITION, pos) }
+  }
+
   fun putPrefFullScreen(fullScreen: Boolean) =
     sharedPreferences.edit { putBoolean(PREF_FULLSCREEN, fullScreen) }
 
@@ -160,10 +167,22 @@ class SharedPreferenceUtil @Inject constructor(val context: Context) {
       _textZooms.offer(textZoom)
     }
 
+  fun getActualPath(path: String): String {
+    var s = path
+    val separator = "/Android"
+    val sepPos = path.indexOf(separator)
+    if (sepPos == -1) {
+    } else {
+      s = path.substring(0, sepPos)
+    }
+    return s
+  }
+
   companion object {
     // Prefs
     const val PREF_LANG = "pref_language_chooser"
     const val PREF_STORAGE = "pref_select_folder"
+    const val STORAGE_POSITION = "storage_position"
     const val PREF_WIFI_ONLY = "pref_wifi_only"
     const val PREF_KIWIX_MOBILE = "kiwix-mobile"
     const val PREF_SHOW_INTRO = "showIntro"