Added a donation popup to our application.

* The donation popup will be shown to the user every three months.
* If the user clicks the "Later" button, the popup will appear again after 3 days.
* The donation popup will only be shown when there is at least one book available in the library. If no ZIM file is present, it’s not ideal to ask for a donation, as the user has not yet used the application.
* The donation popup will only be shown for custom apps when the support_url is configured. If the support menu item is hidden in the sidebar (a feature we offer), the donation popup will not be displayed, as there is no support_url available for that custom app.

core/src/main/java/org/kiwix/kiwixmobile/core/main/CoreMainActivity.kt

@@ -287,7 +287,7 @@ abstract class CoreMainActivity : BaseActivity(), WebViewProvider {
     drawerContainerLayout.closeDrawer(drawerNavView)
   }
 
-  private fun openSupportKiwixExternalLink() {
+  fun openSupportKiwixExternalLink() {
     externalLinkOpener.openExternalUrl(KIWIX_SUPPORT_URL.toUri().browserIntent())
   }
 

core/src/main/java/org/kiwix/kiwixmobile/core/main/CoreReaderFragment.kt

@@ -46,6 +46,7 @@ import android.view.MenuInflater
 import android.view.MenuItem
 import android.view.MotionEvent
 import android.view.View
+import android.view.View.GONE
 import android.view.View.VISIBLE
 import android.view.ViewGroup
 import android.view.animation.AnimationUtils
@@ -133,6 +134,8 @@ import org.kiwix.kiwixmobile.core.reader.ZimReaderSource
 import org.kiwix.kiwixmobile.core.search.viewmodel.effects.SearchItemToOpen
 import org.kiwix.kiwixmobile.core.utils.AnimationUtils.rotate
 import org.kiwix.kiwixmobile.core.utils.DimenUtils.getToolbarHeight
+import org.kiwix.kiwixmobile.core.utils.DonationDialogHandler
+import org.kiwix.kiwixmobile.core.utils.DonationDialogHandler.ShowDonationDialogCallback
 import org.kiwix.kiwixmobile.core.utils.ExternalLinkOpener
 import org.kiwix.kiwixmobile.core.utils.LanguageUtils
 import org.kiwix.kiwixmobile.core.utils.LanguageUtils.Companion.getCurrentLocale
@@ -173,7 +176,8 @@ abstract class CoreReaderFragment :
   FragmentActivityExtensions,
   WebViewProvider,
   ReadAloudCallbacks,
-  NavigationHistoryClickListener {
+  NavigationHistoryClickListener,
+  ShowDonationDialogCallback {
   protected val webViewList: MutableList<KiwixWebView> = ArrayList()
   private val webUrlsProcessor = BehaviorProcessor.create<String>()
   private var fragmentReaderBinding: FragmentReaderBinding? = null
@@ -227,6 +231,10 @@ abstract class CoreReaderFragment :
   @Inject
   var alertDialogShower: DialogShower? = null
 
+  @JvmField
+  @Inject
+  var donationDialogHandler: DonationDialogHandler? = null
+
   @JvmField
   @Inject
   var painter: DarkModeViewPainter? = null
@@ -297,6 +305,7 @@ abstract class CoreReaderFragment :
   private var tableDrawerAdapter: TableDrawerAdapter? = null
   private var tableDrawerRight: RecyclerView? = null
   private var tabCallback: ItemTouchHelper.Callback? = null
+  private var donationLayout: FrameLayout? = null
   private var bookmarkingDisposable: Disposable? = null
   private var isBookmarked = false
   private lateinit var serviceConnection: ServiceConnection
@@ -389,6 +398,7 @@ abstract class CoreReaderFragment :
   ) {
     super.onViewCreated(view, savedInstanceState)
     setupMenu()
+    donationDialogHandler?.showDonationDialogCallBack(this)
     val activity = requireActivity() as AppCompatActivity?
     activity?.let {
       WebView(it).destroy() // Workaround for buggy webViews see #710
@@ -511,6 +521,7 @@ abstract class CoreReaderFragment :
         tabRecyclerView = findViewById(R.id.tab_switcher_recycler_view)
         snackBarRoot = findViewById(R.id.snackbar_root)
         bottomToolbarToc = findViewById(R.id.bottom_toolbar_toc)
+        donationLayout = findViewById(R.id.donation_layout)
       }
     }
   }
@@ -1213,6 +1224,8 @@ abstract class CoreReaderFragment :
     unRegisterReadAloudService()
     storagePermissionForNotesLauncher?.unregister()
     storagePermissionForNotesLauncher = null
+    donationDialogHandler?.showDonationDialogCallBack(null)
+    donationDialogHandler = null
   }
 
   private fun unBindViewsAndBinding() {
@@ -1243,6 +1256,8 @@ abstract class CoreReaderFragment :
     closeAllTabsButton = null
     tableDrawerRightContainer = null
     fragmentReaderBinding = null
+    donationLayout?.removeAllViews()
+    donationLayout = null
   }
 
   private fun updateTableOfContents() {
@@ -1846,6 +1861,53 @@ abstract class CoreReaderFragment :
     if (tts == null) {
       setUpTTS()
     }
+    donationDialogHandler?.attemptToShowDonationPopup()
+  }
+
+  @Suppress("InflateParams", "MagicNumber")
+  protected open fun showDonationLayout() {
+    val donationCardView = layoutInflater.inflate(R.layout.layout_donation_bottom_sheet, null)
+    val layoutParams = FrameLayout.LayoutParams(
+      FrameLayout.LayoutParams.MATCH_PARENT,
+      FrameLayout.LayoutParams.WRAP_CONTENT
+    )
+    val bottomToolBarHeight =
+      requireActivity()
+        .findViewById<BottomAppBar>(org.kiwix.kiwixmobile.core.R.id.bottom_toolbar).measuredHeight
+    layoutParams.setMargins(16, 0, 16, bottomToolBarHeight + 10)
+
+    donationCardView.layoutParams = layoutParams
+    donationLayout?.apply {
+      removeAllViews()
+      addView(donationCardView)
+      setDonationLayoutVisibility(VISIBLE)
+    }
+    donationCardView.findViewById<TextView>(R.id.descriptionText).apply {
+      text = getString(
+        R.string.donation_dialog_description,
+        (requireActivity() as CoreMainActivity).appName
+      )
+    }
+    val donateButton: TextView = donationCardView.findViewById(R.id.donateButton)
+    donateButton.setOnClickListener {
+      donationDialogHandler?.updateLastDonationPopupShownTime()
+      setDonationLayoutVisibility(GONE)
+      openKiwixSupportUrl()
+    }
+
+    val laterButton: TextView = donationCardView.findViewById(R.id.laterButton)
+    laterButton.setOnClickListener {
+      donationDialogHandler?.donateLater()
+      setDonationLayoutVisibility(GONE)
+    }
+  }
+
+  protected open fun openKiwixSupportUrl() {
+    (requireActivity() as CoreMainActivity).openSupportKiwixExternalLink()
+  }
+
+  private fun setDonationLayoutVisibility(visibility: Int) {
+    donationLayout?.visibility = visibility
   }
 
   private fun openFullScreenIfEnabled() {
@@ -2388,6 +2450,10 @@ abstract class CoreReaderFragment :
     unbindService()
   }
 
+  override fun showDonationDialog() {
+    showDonationLayout()
+  }
+
   private fun bindService() {
     requireActivity().bindService(
       Intent(requireActivity(), ReadAloudService::class.java), serviceConnection,

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

@@ -0,0 +1,82 @@
+/*
+ * Kiwix Android
+ * Copyright (c) 2024 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.utils
+
+import android.app.Activity
+import org.kiwix.kiwixmobile.core.dao.NewBookDao
+import org.kiwix.kiwixmobile.core.extensions.ActivityExtensions.isCustomApp
+import javax.inject.Inject
+
+const val THREE_DAYS_IN_MILLISECONDS = 3 * 24 * 60 * 60 * 1000L
+const val THREE_MONTHS_IN_MILLISECONDS = 90 * 24 * 60 * 60 * 1000L
+
+class DonationDialogHandler @Inject constructor(
+  private val activity: Activity,
+  private val sharedPreferenceUtil: SharedPreferenceUtil,
+  private val newBookDao: NewBookDao
+) {
+
+  private var showDonationDialogCallback: ShowDonationDialogCallback? = null
+
+  fun showDonationDialogCallBack(showDonationDialogCallback: ShowDonationDialogCallback?) {
+    this.showDonationDialogCallback = showDonationDialogCallback
+  }
+
+  fun attemptToShowDonationPopup() {
+    val currentMilliSeconds = System.currentTimeMillis()
+    val lastPopupMillis = sharedPreferenceUtil.lastDonationPopupShownInMilliSeconds
+    val timeDifference = currentMilliSeconds - lastPopupMillis
+    if (shouldShowInitialPopup(lastPopupMillis) || timeDifference >= THREE_MONTHS_IN_MILLISECONDS) {
+      if (isZimFilesAvailableInLibrary() && isTimeToShowDonation(currentMilliSeconds)) {
+        showDonationDialogCallback?.showDonationDialog()
+        resetDonateLater()
+      }
+    }
+  }
+
+  private fun shouldShowInitialPopup(lastPopupMillis: Long): Boolean = lastPopupMillis == 0L
+  private fun isTimeToShowDonation(currentMillis: Long): Boolean =
+    isLaterNotClicked() || isLaterPeriodOver(currentMillis)
+
+  private fun isLaterNotClicked(): Boolean = sharedPreferenceUtil.laterClickedMilliSeconds == 0L
+
+  private fun isLaterPeriodOver(currentMillis: Long): Boolean {
+    val timeDifference = currentMillis - sharedPreferenceUtil.laterClickedMilliSeconds
+    return timeDifference >= THREE_DAYS_IN_MILLISECONDS
+  }
+
+  private fun isZimFilesAvailableInLibrary(): Boolean =
+    if (activity.isCustomApp()) true else newBookDao.getBooks().isNotEmpty()
+
+  fun updateLastDonationPopupShownTime() {
+    sharedPreferenceUtil.lastDonationPopupShownInMilliSeconds = System.currentTimeMillis()
+  }
+
+  fun donateLater() {
+    sharedPreferenceUtil.laterClickedMilliSeconds = System.currentTimeMillis()
+  }
+
+  private fun resetDonateLater() {
+    sharedPreferenceUtil.laterClickedMilliSeconds = 0L
+  }
+
+  interface ShowDonationDialogCallback {
+    fun showDonationDialog()
+  }
+}

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

@@ -271,6 +271,22 @@ class SharedPreferenceUtil @Inject constructor(val context: Context) {
       }
     }
 
+  var lastDonationPopupShownInMilliSeconds: Long
+    get() = sharedPreferences.getLong(PREF_LAST_DONATION_POPUP_SHOWN_IN_MILLISECONDS, 0L)
+    set(value) {
+      sharedPreferences.edit {
+        putLong(PREF_LAST_DONATION_POPUP_SHOWN_IN_MILLISECONDS, value)
+      }
+    }
+
+  var laterClickedMilliSeconds: Long
+    get() = sharedPreferences.getLong(PREF_LATER_CLICKED_MILLIS, 0L)
+    set(value) {
+      sharedPreferences.edit {
+        putLong(PREF_LATER_CLICKED_MILLIS, value)
+      }
+    }
+
   fun getPublicDirectoryPath(path: String): String =
     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
       path
@@ -321,5 +337,8 @@ class SharedPreferenceUtil @Inject constructor(val context: Context) {
     const val PREF_NOTES_MIGRATED = "pref_notes_migrated"
     const val PREF_APP_DIRECTORY_TO_PUBLIC_MIGRATED = "pref_app_directory_to_public_migrated"
     const val PREF_COPY_MOVE_PERMISSION = "pref_copy_move_permission"
+    private const val PREF_LATER_CLICKED_MILLIS = "pref_later_clicked_millis"
+    private const val PREF_LAST_DONATION_POPUP_SHOWN_IN_MILLISECONDS =
+      "pref_last_donation_shown_in_milliseconds"
   }
 }

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

@@ -57,6 +57,14 @@
       android:layout_height="match_parent"
       android:background="@android:color/black"
       android:visibility="invisible" />
+
+    <FrameLayout
+      android:id="@+id/donation_layout"
+      android:layout_width="match_parent"
+      android:layout_height="wrap_content"
+      android:visibility="visible"
+      app:layout_constraintBottom_toBottomOf="parent"
+      android:layout_margin="@dimen/activity_horizontal_margin" />
   </androidx.constraintlayout.widget.ConstraintLayout>
 
 </androidx.drawerlayout.widget.DrawerLayout>

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

@@ -0,0 +1,87 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+  ~ Kiwix Android
+  ~ Copyright (c) 2024 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/>.
+  ~
+  -->
+
+<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
+  xmlns:app="http://schemas.android.com/apk/res-auto"
+  android:layout_width="match_parent"
+  android:layout_height="wrap_content"
+  android:layout_margin="16dp"
+  android:padding="16dp"
+  app:cardCornerRadius="12dp"
+  app:cardElevation="6dp">
+
+  <androidx.constraintlayout.widget.ConstraintLayout
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content">
+
+    <ImageView
+      android:id="@+id/heart_icon"
+      android:layout_width="40dp"
+      android:layout_height="40dp"
+      android:layout_alignParentStart="true"
+      android:layout_margin="@dimen/activity_horizontal_margin"
+      android:layout_marginEnd="12dp"
+      android:contentDescription="@string/donation_dialog_title"
+      android:src="@drawable/ic_support_24px"
+      app:layout_constraintStart_toStartOf="parent"
+      app:layout_constraintTop_toTopOf="parent" />
+
+    <TextView
+      android:id="@+id/titleText"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:layout_marginStart="@dimen/fullscreen_control_button_margin"
+      android:text="@string/donation_dialog_title"
+      android:textSize="16sp"
+      android:textAppearance="@style/TextAppearance.M3.Sys.Typescale.TitleMedium"
+      android:textColor="@color/mine_shaft_gray900"
+      app:layout_constraintStart_toEndOf="@id/heart_icon"
+      app:layout_constraintTop_toTopOf="@+id/heart_icon" />
+
+    <TextView
+      android:id="@+id/descriptionText"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:layout_marginTop="4dp"
+      android:text="@string/donation_dialog_description"
+      android:textSize="14sp"
+      app:layout_constraintStart_toStartOf="@id/titleText"
+      app:layout_constraintTop_toBottomOf="@+id/titleText" />
+
+    <TextView
+      android:id="@+id/laterButton"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:padding="@dimen/activity_horizontal_margin"
+      android:text="@string/rate_dialog_neutral"
+      android:textColor="@color/denim_blue800"
+      app:layout_constraintEnd_toStartOf="@+id/donateButton"
+      app:layout_constraintTop_toBottomOf="@id/descriptionText" />
+
+    <TextView
+      android:id="@+id/donateButton"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:padding="@dimen/activity_horizontal_margin"
+      android:text="@string/make_donation"
+      android:textColor="@color/denim_blue800"
+      app:layout_constraintEnd_toEndOf="parent"
+      app:layout_constraintTop_toBottomOf="@id/descriptionText" />
+  </androidx.constraintlayout.widget.ConstraintLayout>
+</androidx.cardview.widget.CardView>
+

core/src/main/res/values/strings.xml

@@ -389,4 +389,7 @@
   <string name="toolbar_back_button_content_description">Go to previous screen</string>
   <string name="save_or_open_unsupported_files_dialog_title">Save or Open this file?</string>
   <string name="save_or_open_unsupported_files_dialog_message">Choosing Open will open this file in external reader application.</string>
+  <string name="donation_dialog_title">Donate Today</string>
+  <string name="donation_dialog_description">%s needs your help.</string>
+  <string name="make_donation">Make a donation</string>
 </resources>

custom/src/main/java/org/kiwix/kiwixmobile/custom/main/CustomReaderFragment.kt

@@ -28,10 +28,12 @@ import android.view.View.VISIBLE
 import android.widget.ImageView
 import androidx.appcompat.app.AppCompatActivity
 import androidx.appcompat.widget.Toolbar
+import androidx.core.net.toUri
 import androidx.drawerlayout.widget.DrawerLayout
 import androidx.navigation.fragment.findNavController
 import org.kiwix.kiwixmobile.core.R.dimen
 import org.kiwix.kiwixmobile.core.base.BaseActivity
+import org.kiwix.kiwixmobile.core.extensions.browserIntent
 import org.kiwix.kiwixmobile.core.extensions.getResizedDrawable
 import org.kiwix.kiwixmobile.core.extensions.isFileExist
 import org.kiwix.kiwixmobile.core.main.CoreReaderFragment
@@ -328,6 +330,22 @@ class CustomReaderFragment : CoreReaderFragment() {
     newMainPageTab()
   }
 
+  /**
+   * Overrides the method to show the donation popup. When the "Support url" is disabled
+   * in a custom app, this function stop to show the donationPopup.
+   */
+  override fun showDonationLayout() {
+    if (BuildConfig.SUPPORT_URL.isNotEmpty()) {
+      super.showDonationLayout()
+    }
+  }
+
+  override fun openKiwixSupportUrl() {
+    if (BuildConfig.SUPPORT_URL.isNotEmpty()) {
+      openExternalUrl(BuildConfig.SUPPORT_URL.toUri().browserIntent())
+    }
+  }
+
   override fun onDestroyView() {
     super.onDestroyView()
     permissionRequiredDialog = null