Convert ZimHostActivity to Kotlin

.idea/codeStyles/Project.xml

@@ -10,9 +10,6 @@
       </value>
     </option>
     <option name="LINE_SEPARATOR" value="&#10;" />
-    <AndroidXmlCodeStyleSettings>
-      <option name="ARRANGEMENT_SETTINGS_MIGRATED_TO_191" value="true" />
-    </AndroidXmlCodeStyleSettings>
     <GroovyCodeStyleSettings>
       <option name="ALIGN_MULTILINE_LIST_OR_MAP" value="false" />
       <option name="ALIGN_NAMED_ARGS_IN_MAP" value="false" />

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

@@ -30,7 +30,7 @@ class AlertDialogShower @Inject constructor(
 ) : DialogShower {
   override fun show(
     dialog: KiwixDialog,
-    vararg clickListeners: () -> Unit
+    vararg clickListeners: (() -> Unit)?
   ) {
 
     AlertDialog.Builder(activity, dialogStyle())

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

@@ -20,6 +20,6 @@ package org.kiwix.kiwixmobile.core.utils
 interface DialogShower {
   fun show(
     dialog: KiwixDialog,
-    vararg clickListeners: () -> Unit
+    vararg clickListeners: (() -> Unit)?
   )
 }

core/src/main/java/org/kiwix/kiwixmobile/core/webserver/ZimHostActivity.java

@@ -1,322 +0,0 @@
-/*
- * Kiwix Android
- * Copyright (c) 2019 Kiwix <android.kiwix.org>
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- *
- */
-
-package org.kiwix.kiwixmobile.core.webserver;
-
-import android.app.ProgressDialog;
-import android.content.ComponentName;
-import android.content.Context;
-import android.content.Intent;
-import android.content.ServiceConnection;
-import android.os.Bundle;
-import android.os.IBinder;
-import android.util.Log;
-import android.widget.Button;
-import android.widget.TextView;
-import android.widget.Toast;
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-import androidx.appcompat.widget.Toolbar;
-import androidx.recyclerview.widget.RecyclerView;
-import butterknife.BindView;
-import butterknife.OnClick;
-import java.io.File;
-import java.util.ArrayList;
-import java.util.HashSet;
-import java.util.List;
-import javax.inject.Inject;
-import kotlin.Unit;
-import org.kiwix.kiwixmobile.core.R;
-import org.kiwix.kiwixmobile.core.R2;
-import org.kiwix.kiwixmobile.core.base.BaseActivity;
-import org.kiwix.kiwixmobile.core.utils.AlertDialogShower;
-import org.kiwix.kiwixmobile.core.utils.KiwixDialog;
-import org.kiwix.kiwixmobile.core.utils.ServerUtils;
-import org.kiwix.kiwixmobile.core.wifi_hotspot.HotspotService;
-import org.kiwix.kiwixmobile.core.zim_manager.fileselect_view.SelectionMode;
-import org.kiwix.kiwixmobile.core.zim_manager.fileselect_view.adapter.BookOnDiskDelegate;
-import org.kiwix.kiwixmobile.core.zim_manager.fileselect_view.adapter.BooksOnDiskAdapter;
-import org.kiwix.kiwixmobile.core.zim_manager.fileselect_view.adapter.BooksOnDiskListItem;
-
-import static org.kiwix.kiwixmobile.core.wifi_hotspot.HotspotService.ACTION_CHECK_IP_ADDRESS;
-import static org.kiwix.kiwixmobile.core.wifi_hotspot.HotspotService.ACTION_START_SERVER;
-import static org.kiwix.kiwixmobile.core.wifi_hotspot.HotspotService.ACTION_STOP_SERVER;
-
-public class ZimHostActivity extends BaseActivity implements
-  ZimHostCallbacks, ZimHostContract.View {
-
-  public static final String SELECTED_ZIM_PATHS_KEY = "selected_zim_paths";
-  private static final String TAG = "ZimHostActivity";
-  private static final String IP_STATE_KEY = "ip_state_key";
-  @BindView(R2.id.startServerButton)
-  Button startServerButton;
-  @BindView(R2.id.server_textView)
-  TextView serverTextView;
-  @BindView(R2.id.recycler_view_zim_host)
-  RecyclerView recyclerViewZimHost;
-  @Inject
-  ZimHostContract.Presenter presenter;
-  @Inject
-  AlertDialogShower alertDialogShower;
-  private BooksOnDiskAdapter booksAdapter;
-  private BookOnDiskDelegate.BookDelegate bookDelegate;
-  private HotspotService hotspotService;
-  private String ip;
-  private ServiceConnection serviceConnection;
-  private ProgressDialog progressDialog;
-  private HashSet<String> selectedBooksId = new HashSet<>();
-
-  @Override
-  protected void onCreate(@Nullable Bundle savedInstanceState) {
-    super.onCreate(savedInstanceState);
-    setContentView(R.layout.activity_zim_host);
-
-    setUpToolbar();
-
-    bookDelegate =
-      new BookOnDiskDelegate.BookDelegate(sharedPreferenceUtil,
-        null,
-        null,
-        bookOnDiskItem -> {
-          select(bookOnDiskItem);
-          return Unit.INSTANCE;
-        });
-    bookDelegate.setSelectionMode(SelectionMode.MULTI);
-    booksAdapter = new BooksOnDiskAdapter(bookDelegate,
-      BookOnDiskDelegate.LanguageDelegate.INSTANCE
-    );
-    if (savedInstanceState != null) {
-      ip = savedInstanceState.getString(IP_STATE_KEY);
-      layoutServerStarted();
-    }
-    recyclerViewZimHost.setAdapter(booksAdapter);
-    presenter.attachView(this);
-
-    serviceConnection = new ServiceConnection() {
-
-      @Override
-      public void onServiceConnected(ComponentName className, IBinder service) {
-        hotspotService = ((HotspotService.HotspotBinder) service).getService();
-        hotspotService.registerCallBack(ZimHostActivity.this);
-      }
-
-      @Override
-      public void onServiceDisconnected(ComponentName arg0) {
-      }
-    };
-  }
-
-  @OnClick(R2.id.startServerButton) void startStopServer() {
-    if (ServerUtils.isServerStarted) {
-      stopServer();
-    } else if (getSelectedBooksPath().size() > 0) {
-      startHotspotManuallyDialog();
-    } else {
-      Toast.makeText(this, R.string.no_books_selected_toast_message, Toast.LENGTH_SHORT).show();
-    }
-  }
-
-  private void stopServer() {
-    startService(createHotspotIntent(ACTION_STOP_SERVER));
-  }
-
-  private ArrayList<String> getSelectedBooksPath() {
-    ArrayList<String> selectedBooksPath = new ArrayList<>();
-    for (BooksOnDiskListItem item : booksAdapter.getItems()) {
-      if (item.isSelected()) {
-        BooksOnDiskListItem.BookOnDisk bookOnDisk = (BooksOnDiskListItem.BookOnDisk) item;
-        File file = bookOnDisk.getFile();
-        selectedBooksPath.add(file.getAbsolutePath());
-        Log.v(TAG, "ZIM PATH : " + file.getAbsolutePath());
-      }
-    }
-    return selectedBooksPath;
-  }
-
-  private void select(@NonNull BooksOnDiskListItem.BookOnDisk bookOnDisk) {
-    bookOnDisk.setSelected(!bookOnDisk.isSelected());
-    if (bookOnDisk.isSelected()) {
-      selectedBooksId.add(bookOnDisk.getBook().getId());
-    } else {
-      selectedBooksId.remove(bookOnDisk.getBook().getId());
-    }
-    booksAdapter.notifyDataSetChanged();
-    saveHostedBooks();
-  }
-
-  @Override protected void onStart() {
-    super.onStart();
-    bindService();
-  }
-
-  @Override protected void onStop() {
-    super.onStop();
-    unbindService();
-  }
-
-  private void bindService() {
-    bindService(new Intent(this, HotspotService.class), serviceConnection,
-      Context.BIND_AUTO_CREATE);
-  }
-
-  private void unbindService() {
-    if (hotspotService != null) {
-      unbindService(serviceConnection);
-      hotspotService.registerCallBack(null);
-    }
-  }
-
-  @Override protected void onResume() {
-    super.onResume();
-    presenter.loadBooks();
-    if (ServerUtils.isServerStarted) {
-      ip = ServerUtils.getSocketAddress();
-      layoutServerStarted();
-    }
-  }
-
-  private void saveHostedBooks() {
-    sharedPreferenceUtil.setHostedBooks(selectedBooksId);
-  }
-
-  private void layoutServerStarted() {
-    serverTextView.setText(getString(R.string.server_started_message, ip));
-    startServerButton.setText(getString(R.string.stop_server_label));
-    startServerButton.setBackgroundColor(getResources().getColor(R.color.stopServer));
-    bookDelegate.setSelectionMode(SelectionMode.NORMAL);
-    booksAdapter.notifyDataSetChanged();
-  }
-
-  private void layoutServerStopped() {
-    serverTextView.setText(getString(R.string.server_textview_default_message));
-    startServerButton.setText(getString(R.string.start_server_label));
-    startServerButton.setBackgroundColor(getResources().getColor(R.color.greenTick));
-    bookDelegate.setSelectionMode(SelectionMode.MULTI);
-    booksAdapter.notifyDataSetChanged();
-  }
-
-  @Override protected void onDestroy() {
-    super.onDestroy();
-    presenter.detachView();
-  }
-
-  private void setUpToolbar() {
-    Toolbar toolbar = findViewById(R.id.toolbar);
-    setSupportActionBar(toolbar);
-    getSupportActionBar().setTitle(getString(R.string.menu_host_books));
-    getSupportActionBar().setHomeButtonEnabled(true);
-    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
-
-    toolbar.setNavigationOnClickListener(v -> onBackPressed());
-  }
-
-  //Advice user to turn on hotspot manually for API<26
-  private void startHotspotManuallyDialog() {
-
-    alertDialogShower.show(new KiwixDialog.StartHotspotManually(),
-      () -> {
-        launchTetheringSettingsScreen();
-        return Unit.INSTANCE;
-      },
-      null,
-      () -> {
-        progressDialog =
-          ProgressDialog.show(this,
-            getString(R.string.progress_dialog_starting_server), "",
-            true);
-        startService(createHotspotIntent(ACTION_CHECK_IP_ADDRESS));
-        return Unit.INSTANCE;
-      }
-    );
-  }
-
-  private Intent createHotspotIntent(String action) {
-    return new Intent(this, HotspotService.class).setAction(action);
-  }
-
-  @Override public void onServerStarted(@NonNull String ipAddress) {
-    this.ip = ipAddress;
-    layoutServerStarted();
-  }
-
-  @Override public void onServerStopped() {
-    layoutServerStopped();
-  }
-
-  @Override public void onServerFailedToStart() {
-    Toast.makeText(this, R.string.server_failed_toast_message, Toast.LENGTH_LONG).show();
-  }
-
-  private void launchTetheringSettingsScreen() {
-    final Intent intent = new Intent(Intent.ACTION_MAIN, null);
-    intent.addCategory(Intent.CATEGORY_LAUNCHER);
-    final ComponentName cn =
-      new ComponentName("com.android.settings", "com.android.settings.TetherSettings");
-    intent.setComponent(cn);
-    intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
-    startActivity(intent);
-  }
-
-  @Override protected void onSaveInstanceState(@Nullable Bundle outState) {
-    super.onSaveInstanceState(outState);
-    if (ServerUtils.isServerStarted) {
-      outState.putString(IP_STATE_KEY, ip);
-    }
-  }
-
-  @Override public void addBooks(@Nullable List<BooksOnDiskListItem> books) {
-    selectPreviouslyHostedBooks(books);
-    booksAdapter.setItems(books);
-  }
-
-  @Override public void onIpAddressValid() {
-    progressDialog.dismiss();
-    startService(createHotspotIntent(ACTION_START_SERVER).putStringArrayListExtra(
-      SELECTED_ZIM_PATHS_KEY, getSelectedBooksPath()));
-  }
-
-  @Override public void onIpAddressInvalid() {
-    progressDialog.dismiss();
-    Toast.makeText(this, R.string.server_failed_message,
-      Toast.LENGTH_SHORT)
-      .show();
-  }
-
-  private void selectPreviouslyHostedBooks(@Nullable List<BooksOnDiskListItem> books) {
-    selectedBooksId.addAll(sharedPreferenceUtil.getHostedBooks());
-    if (books != null && !books.isEmpty()) {
-      if (selectedBooksId.isEmpty()) {
-        // Select all books if no book ids are stored
-        for (BooksOnDiskListItem book : books) {
-          if (book instanceof BooksOnDiskListItem.BookOnDisk) {
-            selectedBooksId.add(((BooksOnDiskListItem.BookOnDisk) book).getBook().getId());
-            book.setSelected(true);
-          }
-        }
-      } else {
-        for (BooksOnDiskListItem book : books) {
-          if (book instanceof BooksOnDiskListItem.BookOnDisk) {
-            book.setSelected(
-              selectedBooksId.contains(((BooksOnDiskListItem.BookOnDisk) book).getBook().getId())
-            );
-          }
-        }
-      }
-    }
-  }
-}

core/src/main/java/org/kiwix/kiwixmobile/core/webserver/ZimHostActivity.kt

@@ -0,0 +1,309 @@
+/*
+ * Kiwix Android
+ * Copyright (c) 2019 Kiwix <android.kiwix.org>
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package org.kiwix.kiwixmobile.core.webserver
+
+import android.app.ProgressDialog
+import android.content.ComponentName
+import android.content.Context
+import android.content.Intent
+import android.content.ServiceConnection
+import android.os.Bundle
+import android.os.IBinder
+import android.util.Log
+import android.widget.Toast
+import androidx.appcompat.widget.Toolbar
+import kotlinx.android.synthetic.main.activity_zim_host.recyclerViewZimHost
+import kotlinx.android.synthetic.main.activity_zim_host.serverTextView
+import kotlinx.android.synthetic.main.activity_zim_host.startServerButton
+import org.kiwix.kiwixmobile.core.R
+import org.kiwix.kiwixmobile.core.base.BaseActivity
+import org.kiwix.kiwixmobile.core.utils.AlertDialogShower
+import org.kiwix.kiwixmobile.core.utils.KiwixDialog
+import org.kiwix.kiwixmobile.core.utils.ServerUtils
+import org.kiwix.kiwixmobile.core.wifi_hotspot.HotspotService
+import org.kiwix.kiwixmobile.core.wifi_hotspot.HotspotService.ACTION_CHECK_IP_ADDRESS
+import org.kiwix.kiwixmobile.core.wifi_hotspot.HotspotService.ACTION_START_SERVER
+import org.kiwix.kiwixmobile.core.wifi_hotspot.HotspotService.ACTION_STOP_SERVER
+import org.kiwix.kiwixmobile.core.zim_manager.fileselect_view.SelectionMode
+import org.kiwix.kiwixmobile.core.zim_manager.fileselect_view.adapter.BookOnDiskDelegate
+import org.kiwix.kiwixmobile.core.zim_manager.fileselect_view.adapter.BooksOnDiskAdapter
+import org.kiwix.kiwixmobile.core.zim_manager.fileselect_view.adapter.BooksOnDiskListItem
+import java.util.ArrayList
+import java.util.HashSet
+import javax.inject.Inject
+
+class ZimHostActivity : BaseActivity(), ZimHostCallbacks, ZimHostContract.View {
+  @Inject
+  internal lateinit var presenter: ZimHostContract.Presenter
+  @Inject
+  internal lateinit var alertDialogShower: AlertDialogShower
+  private lateinit var booksAdapter: BooksOnDiskAdapter
+  private lateinit var bookDelegate: BookOnDiskDelegate.BookDelegate
+  private var hotspotService: HotspotService? = null
+  private var ip: String? = null
+  private var serviceConnection: ServiceConnection? = null
+  private var progressDialog: ProgressDialog? = null
+  private val selectedBooksId = HashSet<String>()
+  private val tag = "ZimHostActivity"
+  private val ipStateKey = "ip_state_key"
+
+  private val selectedBooksPath: ArrayList<String>
+    get() {
+      val selectedBooksPath = ArrayList<String>()
+      for (item in booksAdapter.items) {
+        if (item.isSelected) {
+          val (_, _, file) = item as BooksOnDiskListItem.BookOnDisk
+          selectedBooksPath.add(file.absolutePath)
+          Log.v(tag, "ZIM PATH : " + file.absolutePath)
+        }
+      }
+      return selectedBooksPath
+    }
+
+  override fun onCreate(savedInstanceState: Bundle?) {
+    super.onCreate(savedInstanceState)
+    setContentView(R.layout.activity_zim_host)
+
+    setUpToolbar()
+
+    bookDelegate = BookOnDiskDelegate.BookDelegate(sharedPreferenceUtil, null, null,
+      { bookOnDiskItem ->
+        select(bookOnDiskItem)
+        Unit
+      })
+    bookDelegate.selectionMode = SelectionMode.MULTI
+    booksAdapter = BooksOnDiskAdapter(
+      bookDelegate,
+      BookOnDiskDelegate.LanguageDelegate
+    )
+    if (savedInstanceState != null) {
+      ip = savedInstanceState.getString(ipStateKey)
+      layoutServerStarted()
+    }
+    recyclerViewZimHost.adapter = booksAdapter
+    presenter.attachView(this)
+
+    serviceConnection = object : ServiceConnection {
+
+      override fun onServiceConnected(className: ComponentName, service: IBinder) {
+        hotspotService = (service as HotspotService.HotspotBinder).service
+        hotspotService!!.registerCallBack(this@ZimHostActivity)
+      }
+
+      override fun onServiceDisconnected(arg0: ComponentName) {}
+    }
+
+    startServerButton.setOnClickListener { startStopServer() }
+  }
+
+  private fun startStopServer() {
+    when {
+      ServerUtils.isServerStarted -> stopServer()
+      selectedBooksPath.size > 0 -> startHotspotManuallyDialog()
+      else -> Toast.makeText(
+        this,
+        R.string.no_books_selected_toast_message,
+        Toast.LENGTH_SHORT
+      ).show()
+    }
+  }
+
+  private fun stopServer() {
+    startService(createHotspotIntent(ACTION_STOP_SERVER))
+  }
+
+  private fun select(bookOnDisk: BooksOnDiskListItem.BookOnDisk) {
+    bookOnDisk.isSelected = !bookOnDisk.isSelected
+    if (bookOnDisk.isSelected) {
+      selectedBooksId.add(bookOnDisk.book.getId())
+    } else {
+      selectedBooksId.remove(bookOnDisk.book.getId())
+    }
+    booksAdapter.notifyDataSetChanged()
+    saveHostedBooks()
+  }
+
+  override fun onStart() {
+    super.onStart()
+    bindService()
+  }
+
+  override fun onStop() {
+    super.onStop()
+    unbindService()
+  }
+
+  private fun bindService() {
+    bindService(
+      Intent(this, HotspotService::class.java), serviceConnection,
+      Context.BIND_AUTO_CREATE
+    )
+  }
+
+  private fun unbindService() {
+    if (hotspotService != null) {
+      unbindService(serviceConnection)
+      hotspotService!!.registerCallBack(null)
+    }
+  }
+
+  override fun onResume() {
+    super.onResume()
+    presenter.loadBooks()
+    if (ServerUtils.isServerStarted) {
+      ip = ServerUtils.getSocketAddress()
+      layoutServerStarted()
+    }
+  }
+
+  private fun saveHostedBooks() {
+    sharedPreferenceUtil.hostedBooks = selectedBooksId
+  }
+
+  private fun layoutServerStarted() {
+    serverTextView.text = getString(R.string.server_started_message, ip)
+    startServerButton.text = getString(R.string.stop_server_label)
+    startServerButton.setBackgroundColor(resources.getColor(R.color.stopServer))
+    bookDelegate.selectionMode = SelectionMode.NORMAL
+    booksAdapter.notifyDataSetChanged()
+  }
+
+  private fun layoutServerStopped() {
+    serverTextView.text = getString(R.string.server_textview_default_message)
+    startServerButton.text = getString(R.string.start_server_label)
+    startServerButton.setBackgroundColor(resources.getColor(R.color.greenTick))
+    bookDelegate.selectionMode = SelectionMode.MULTI
+    booksAdapter.notifyDataSetChanged()
+  }
+
+  override fun onDestroy() {
+    super.onDestroy()
+    presenter.detachView()
+  }
+
+  private fun setUpToolbar() {
+    val toolbar = findViewById<Toolbar>(R.id.toolbar)
+    setSupportActionBar(toolbar)
+    supportActionBar!!.title = getString(R.string.menu_host_books)
+    supportActionBar!!.setHomeButtonEnabled(true)
+    supportActionBar!!.setDisplayHomeAsUpEnabled(true)
+
+    toolbar.setNavigationOnClickListener { onBackPressed() }
+  }
+
+  // Advice user to turn on hotspot manually for API<26
+  private fun startHotspotManuallyDialog() {
+
+    alertDialogShower.show(KiwixDialog.StartHotspotManually(),
+      {
+        launchTetheringSettingsScreen()
+        Unit
+      },
+      null,
+      {
+        progressDialog = ProgressDialog.show(
+          this,
+          getString(R.string.progress_dialog_starting_server), "",
+          true
+        )
+        startService(createHotspotIntent(ACTION_CHECK_IP_ADDRESS))
+        Unit
+      }
+    )
+  }
+
+  private fun createHotspotIntent(action: String): Intent =
+    Intent(this, HotspotService::class.java).setAction(action)
+
+  override fun onServerStarted(ipAddress: String) {
+    ip = ipAddress
+    layoutServerStarted()
+  }
+
+  override fun onServerStopped() {
+    layoutServerStopped()
+  }
+
+  override fun onServerFailedToStart() {
+    Toast.makeText(this, R.string.server_failed_toast_message, Toast.LENGTH_LONG).show()
+  }
+
+  private fun launchTetheringSettingsScreen() {
+    val intent = Intent(Intent.ACTION_MAIN, null)
+    intent.addCategory(Intent.CATEGORY_LAUNCHER)
+    val cn = ComponentName("com.android.settings", "com.android.settings.TetherSettings")
+    intent.component = cn
+    intent.flags = Intent.FLAG_ACTIVITY_NEW_TASK
+    startActivity(intent)
+  }
+
+  override fun onSaveInstanceState(outState: Bundle?) {
+    super.onSaveInstanceState(outState)
+    if (ServerUtils.isServerStarted) {
+      outState!!.putString(ipStateKey, ip)
+    }
+  }
+
+  override fun addBooks(books: List<BooksOnDiskListItem>) {
+    selectPreviouslyHostedBooks(books)
+    booksAdapter.items = books
+  }
+
+  override fun onIpAddressValid() {
+    progressDialog!!.dismiss()
+    startService(
+      createHotspotIntent(ACTION_START_SERVER).putStringArrayListExtra(
+        SELECTED_ZIM_PATHS_KEY, selectedBooksPath
+      )
+    )
+  }
+
+  override fun onIpAddressInvalid() {
+    progressDialog!!.dismiss()
+    Toast.makeText(
+      this, R.string.server_failed_message,
+      Toast.LENGTH_SHORT
+    )
+      .show()
+  }
+
+  private fun selectPreviouslyHostedBooks(books: List<BooksOnDiskListItem>?) {
+    selectedBooksId.addAll(sharedPreferenceUtil.hostedBooks)
+    if (books != null && books.isNotEmpty()) {
+      if (selectedBooksId.isEmpty()) {
+        // Select all books if no book ids are stored
+        for (book in books) {
+          if (book is BooksOnDiskListItem.BookOnDisk) {
+            selectedBooksId.add(book.book.getId())
+            book.isSelected = true
+          }
+        }
+      } else {
+        books
+          .asSequence()
+          .filterIsInstance<BooksOnDiskListItem.BookOnDisk>()
+          .forEach { it.isSelected = selectedBooksId.contains(it.book.getId()) }
+      }
+    }
+  }
+
+  companion object {
+    const val SELECTED_ZIM_PATHS_KEY = "selected_zim_paths"
+  }
+}

core/src/main/res/layout/activity_zim_host.xml

@@ -25,7 +25,7 @@
   </com.google.android.material.appbar.AppBarLayout>
 
   <TextView
-    android:id="@+id/server_textView"
+    android:id="@+id/serverTextView"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:layout_marginLeft="16dp"
@@ -37,7 +37,7 @@
     />
 
   <androidx.recyclerview.widget.RecyclerView
-    android:id="@+id/recycler_view_zim_host"
+    android:id="@+id/recyclerViewZimHost"
     android:layout_width="0dp"
     android:layout_height="0dp"
     app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
@@ -46,7 +46,7 @@
     app:layout_constraintBottom_toTopOf="@+id/startServerButton"
     app:layout_constraintLeft_toLeftOf="parent"
     app:layout_constraintRight_toRightOf="parent"
-    app:layout_constraintTop_toBottomOf="@+id/server_textView"
+    app:layout_constraintTop_toBottomOf="@+id/serverTextView"
     />
 
   <Button