Improved PDF file viewer

app/src/main/java/org/linphone/activities/main/files/adapters/PdfPagesListAdapter.kt

@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2010-2021 Belledonne Communications SARL.
+ *
+ * This file is part of linphone-android
+ * (see https://www.linphone.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.linphone.activities.main.files.adapters
+
+import android.view.LayoutInflater
+import android.view.ViewGroup
+import androidx.databinding.DataBindingUtil
+import androidx.recyclerview.widget.RecyclerView
+import org.linphone.R
+import org.linphone.activities.main.files.viewmodels.PdfFileViewModel
+import org.linphone.databinding.PdfViewerCellBinding
+
+class PdfPagesListAdapter(private val pdfViewModel: PdfFileViewModel) : RecyclerView.Adapter<PdfPagesListAdapter.PdfPageViewHolder>() {
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): PdfPageViewHolder {
+        val binding: PdfViewerCellBinding = DataBindingUtil.inflate(
+            LayoutInflater.from(parent.context),
+            R.layout.pdf_viewer_cell, parent, false
+        )
+        return PdfPageViewHolder(binding)
+    }
+
+    override fun getItemCount(): Int {
+        return pdfViewModel.getPagesCount()
+    }
+
+    override fun onBindViewHolder(holder: PdfPageViewHolder, position: Int) {
+        holder.bind(position)
+    }
+
+    inner class PdfPageViewHolder(private val binding: PdfViewerCellBinding) : RecyclerView.ViewHolder(binding.root) {
+        fun bind(index: Int) {
+            with(binding) {
+                pdfViewModel.loadPdfPageInto(index, pdfImage)
+            }
+        }
+    }
+}

app/src/main/java/org/linphone/activities/main/files/fragments/PdfViewerFragment.kt

@@ -22,6 +22,7 @@ package org.linphone.activities.main.files.fragments
 import android.os.Bundle
 import androidx.lifecycle.ViewModelProvider
 import org.linphone.R
+import org.linphone.activities.main.files.adapters.PdfPagesListAdapter
 import org.linphone.activities.main.files.viewmodels.PdfFileViewModel
 import org.linphone.activities.main.files.viewmodels.PdfFileViewModelFactory
 import org.linphone.activities.main.fragments.SecureFragment
@@ -31,6 +32,7 @@ import org.linphone.databinding.PdfViewerFragmentBinding
 class PdfViewerFragment : SecureFragment<PdfViewerFragmentBinding>() {
     private lateinit var viewModel: PdfFileViewModel
     private lateinit var sharedViewModel: SharedMainViewModel
+    private lateinit var adapter: PdfPagesListAdapter
 
     override fun getLayoutId(): Int = R.layout.pdf_viewer_fragment
 
@@ -56,5 +58,9 @@ class PdfViewerFragment : SecureFragment<PdfViewerFragmentBinding>() {
         binding.viewModel = viewModel
 
         isSecure = arguments?.getBoolean("Secure") ?: false
+
+        adapter = PdfPagesListAdapter(viewModel)
+        binding.pdfViewPager.adapter = adapter
+        adapter.notifyDataSetChanged()
     }
 }

app/src/main/java/org/linphone/activities/main/files/viewmodels/PdfFileViewModel.kt

@@ -22,14 +22,11 @@ package org.linphone.activities.main.files.viewmodels
 import android.graphics.Bitmap
 import android.graphics.pdf.PdfRenderer
 import android.os.ParcelFileDescriptor
+import android.widget.ImageView
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.ViewModelProvider
-import androidx.lifecycle.viewModelScope
 import java.io.File
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.launch
-import kotlinx.coroutines.withContext
 import org.linphone.LinphoneApplication.Companion.coreContext
 import org.linphone.core.tools.Log
 
@@ -45,8 +42,6 @@ class PdfFileViewModelFactory(private val filePath: String) :
 class PdfFileViewModel(filePath: String) : ViewModel() {
     val operationInProgress = MutableLiveData<Boolean>()
 
-    val pages = MutableLiveData<ArrayList<PdfPageViewModel>>()
-
     private val pdfRenderer: PdfRenderer
 
     init {
@@ -55,25 +50,21 @@ class PdfFileViewModel(filePath: String) : ViewModel() {
         val input = ParcelFileDescriptor.open(File(filePath), ParcelFileDescriptor.MODE_READ_ONLY)
         pdfRenderer = PdfRenderer(input)
         Log.i("[PDF Viewer] ${pdfRenderer.pageCount} pages in file $filePath")
-
-        loadPdf()
     }
 
     override fun onCleared() {
-        for (page in pages.value.orEmpty()) {
+        pdfRenderer.close()
-            page.destroy()
-        }
-        pages.value?.clear()
         super.onCleared()
     }
 
-    private fun loadPdf() {
+    fun getPagesCount(): Int {
-        viewModelScope.launch {
+        return pdfRenderer.pageCount
-            withContext(Dispatchers.IO) {
+    }
-                try {
+
-                    operationInProgress.postValue(true)
+    fun loadPdfPageInto(index: Int, view: ImageView) {
+        try {
+            operationInProgress.value = true
 
-                    for (index in 0 until pdfRenderer.pageCount) {
             val page: PdfRenderer.Page = pdfRenderer.openPage(index)
             val width = if (coreContext.screenWidth <= coreContext.screenHeight) coreContext.screenWidth else coreContext.screenHeight
             val bm = Bitmap.createBitmap(
@@ -84,25 +75,12 @@ class PdfFileViewModel(filePath: String) : ViewModel() {
             page.render(bm, null, null, PdfRenderer.Page.RENDER_MODE_FOR_DISPLAY)
             page.close()
 
-                        val pageViewModel = PdfPageViewModel(bm)
+            view.setImageBitmap(bm)
-                        val list = arrayListOf<PdfPageViewModel>()
-                        list.addAll(pages.value.orEmpty())
-                        list.add(pageViewModel)
-                        pages.postValue(list)
-                    }
 
-                    operationInProgress.postValue(false)
+            operationInProgress.value = false
         } catch (e: Exception) {
             Log.e("[PDF Viewer] Exception: $e")
-                    operationInProgress.postValue(false)
+            operationInProgress.value = false
-                }
-            }
-        }
-    }
-
-    class PdfPageViewModel(val bitmap: Bitmap) {
-        fun destroy() {
-            bitmap.recycle()
         }
     }
 }

app/src/main/res/layout/pdf_viewer_cell.xml

@@ -3,20 +3,17 @@
 
     <data>
         <import type="android.view.View"/>
-        <variable
-            name="data"
-            type="org.linphone.activities.main.files.viewmodels.PdfFileViewModel.PdfPageViewModel" />
     </data>
 
     <RelativeLayout
         android:layout_width="match_parent"
-        android:layout_height="wrap_content">
+        android:layout_height="match_parent">
 
         <ImageView
+            android:id="@+id/pdf_image"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
-            android:layout_centerHorizontal="true"
+            android:layout_centerHorizontal="true" />
-            android:src="@{data.bitmap}" />
 
     </RelativeLayout>
 

app/src/main/res/layout/pdf_viewer_fragment.xml

@@ -23,19 +23,11 @@
             android:layout_alignParentTop="true"
             tools:layout="@layout/file_viewer_top_bar_fragment" />
 
-        <ScrollView
+        <androidx.viewpager2.widget.ViewPager2
+            android:id="@+id/pdf_view_pager"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
-            android:layout_below="@id/top_bar_fragment">
+            android:layout_below="@id/top_bar_fragment" />
-
-            <LinearLayout
-                android:layout_width="match_parent"
-                android:layout_height="wrap_content"
-                android:orientation="vertical"
-                bind:entries="@{viewModel.pages}"
-                bind:layout="@{@layout/pdf_viewer_cell}"/>
-
-        </ScrollView>
 
         <include
             layout="@layout/wait_layout"