Add PdfBox library for future parsing

Change buttons to chips

app/build.gradle.kts

@@ -51,4 +51,6 @@ dependencies {
     testImplementation(libs.junit)
     androidTestImplementation(libs.androidx.junit)
     androidTestImplementation(libs.androidx.espresso.core)
+
+    implementation(libs.pdfbox.android)
 }

app/src/main/java/com/lhw/pdf/MainActivity.kt

@@ -11,6 +11,8 @@ import android.view.Display
 import android.view.Menu
 import android.view.WindowManager
 import android.widget.ImageView
+import androidx.activity.SystemBarStyle
+import androidx.activity.enableEdgeToEdge
 import com.google.android.material.snackbar.Snackbar
 import com.google.android.material.navigation.NavigationView
 import androidx.navigation.findNavController
@@ -23,6 +25,7 @@ import androidx.appcompat.app.AppCompatActivity
 import androidx.core.view.WindowCompat
 import androidx.core.view.WindowInsetsCompat
 import com.lhw.pdf.databinding.ActivityMainBinding
+import com.tom_roush.pdfbox.android.PDFBoxResourceLoader
 import java.io.File
 import java.io.FileOutputStream
 import java.io.InputStream
@@ -37,6 +40,11 @@ class MainActivity : AppCompatActivity() {
     private val thumbnailHeight = 700
     private var renderAutoCrop = true
     private var pagesPerLandscape = 3F
+        private set(pages) {
+            field = pages
+            updatePresentations()
+        }
+    private var usePdfBox = false
     private val presentations = mutableMapOf<Int, MyPresentation>()
     private lateinit var pdfDocument: PdfDocument
     private val showPages = mutableListOf<Boolean>()
@@ -151,12 +159,15 @@ class MainActivity : AppCompatActivity() {
     }
 
     override fun onCreate(savedInstanceState: Bundle?) {
+        //enableEdgeToEdge()
         super.onCreate(savedInstanceState)
         window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
         displayManager = getSystemService(Context.DISPLAY_SERVICE) as DisplayManager
         //val windowInsetsController = WindowCompat.getInsetsController(window, window.decorView)
         //windowInsetsController.hide(WindowInsetsCompat.Type.systemBars())  //Doesn't seem to actually fill the vacant space by default
 
+        PDFBoxResourceLoader.init(this)
+
         binding = ActivityMainBinding.inflate(layoutInflater)
         setContentView(binding.root)
 
@@ -169,7 +180,7 @@ class MainActivity : AppCompatActivity() {
         if (!file.exists()) {
             file = inputStreamToCache(defaultCachedFileName, resources.openRawResource(R.raw.testpdf))
         }
-        pdfDocument = PdfDocument(file, true)
+        pdfDocument = PdfDocument(file, usePdfBox = false, autoCrop = true)
         // Then overwrite it with any pdf sent via intent
         handleIntent(intent)
 
@@ -184,26 +195,24 @@ class MainActivity : AppCompatActivity() {
             presentations.values.forEach {it.setScrollProgress(progress)}
         }
 
-        binding.appBarMain.crop.setOnClickListener { view ->
+        binding.appBarMain.contentMain.chipPages1.setOnCheckedChangeListener { _, checked -> if (checked) pagesPerLandscape = 1F }
-            renderAutoCrop = !renderAutoCrop
+        binding.appBarMain.contentMain.chipPages15.setOnCheckedChangeListener { _, checked -> if (checked) pagesPerLandscape = 1.5F }
-            val s = if (renderAutoCrop) "On" else "Off"
+        binding.appBarMain.contentMain.chipPages2.setOnCheckedChangeListener { _, checked -> if (checked) pagesPerLandscape = 2F }
-            Snackbar.make(view, "Toggling Auto Crop $s", Snackbar.LENGTH_LONG)
+        binding.appBarMain.contentMain.chipPages25.setOnCheckedChangeListener { _, checked -> if (checked) pagesPerLandscape = 2.5F }
-                .setAction("Action", null)
+        binding.appBarMain.contentMain.chipPages3.setOnCheckedChangeListener { _, checked -> if (checked) pagesPerLandscape = 3F }
-                .setAnchorView(R.id.crop).show()
+        binding.appBarMain.contentMain.chipPages35.setOnCheckedChangeListener { _, checked -> if (checked) pagesPerLandscape = 3.5F }
+        binding.appBarMain.contentMain.chipPages4.setOnCheckedChangeListener { _, checked -> if (checked) pagesPerLandscape = 4F }
+        binding.appBarMain.contentMain.chipPages5.setOnCheckedChangeListener { _, checked -> if (checked) pagesPerLandscape = 5F }
+        binding.appBarMain.contentMain.chipPages6.setOnCheckedChangeListener { _, checked -> if (checked) pagesPerLandscape = 6F }
+        binding.appBarMain.contentMain.chipPages8.setOnCheckedChangeListener { _, checked -> if (checked) pagesPerLandscape = 8F }
+        binding.appBarMain.contentMain.chipPages10.setOnCheckedChangeListener { _, checked -> if (checked) pagesPerLandscape = 10F }
+        binding.appBarMain.contentMain.chipAutoCrop.setOnCheckedChangeListener { _, checked ->
+            renderAutoCrop = checked
             updatePresentations()
         }
-        binding.appBarMain.zoomIn.setOnClickListener { view ->
+        binding.appBarMain.contentMain.chipUsePdfBox.setOnCheckedChangeListener { _, checked ->
-            pagesPerLandscape = max(pagesPerLandscape - 0.5F, 1F)
+            usePdfBox = checked
-            Snackbar.make(view, "Aiming for $pagesPerLandscape pages at a time", Snackbar.LENGTH_LONG)
+            pdfDocument.usePdfBox = usePdfBox
-                .setAction("Action", null)
-                .setAnchorView(R.id.zoom_in).show()
-            updatePresentations()
-        }
-        binding.appBarMain.zoomOut.setOnClickListener { view ->
-            pagesPerLandscape = min(pagesPerLandscape + 0.5F, 10F)
-            Snackbar.make(view, "Aiming for $pagesPerLandscape pages at a time", Snackbar.LENGTH_LONG)
-                .setAction("Action", null)
-                .setAnchorView(R.id.zoom_out).show()
             updatePresentations()
         }
         val drawerLayout: DrawerLayout = binding.drawerLayout

app/src/main/java/com/lhw/pdf/PdfDocument.kt

@@ -7,25 +7,40 @@ import android.graphics.Rect
 import android.graphics.RectF
 import android.graphics.pdf.PdfRenderer
 import android.os.ParcelFileDescriptor
+import com.tom_roush.pdfbox.pdmodel.PDDocument
+import com.tom_roush.pdfbox.rendering.PDFRenderer
 import java.io.File
 import kotlin.math.max
 import kotlin.math.min
 
-class PdfDocument(private val fileCached: File, private val autoCrop: Boolean = false) {
+class PdfDocument(private val fileCached: File, var usePdfBox: Boolean = true, private val autoCrop: Boolean = false) {
+    // Stock Android PdfRenderer - fast but limited
     private val pfd = ParcelFileDescriptor.open(fileCached, ParcelFileDescriptor.MODE_READ_ONLY)
     private val renderer = PdfRenderer(pfd)
-    val bitmapThumbnails = mutableMapOf<Int, Bitmap>()
-    val bitmapPages = mutableMapOf<Pair<Int, Int>, MutableMap<Int, Bitmap>>()  // bitmapPages[<maxWidthPx, maxHeightPx>][pageId]
     private val pagePtWidths = mutableListOf<Int>()
     private val pagePtHeights = mutableListOf<Int>()
+    // PdfBox parser/renderer - powerful but slow
+    private val pdfDocument = PDDocument.load(fileCached)
+    private val boxRenderer = PDFRenderer(pdfDocument)
+    private val boxPagePtWidths = mutableListOf<Float>()
+    private val boxPagePtHeights = mutableListOf<Float>()
+
+    val bitmapThumbnails = mutableMapOf<Int, Bitmap>()
+    val bitmapPages = mutableMapOf<Pair<Int, Int>, MutableMap<Int, Bitmap>>()  // bitmapPages[<maxWidthPx, maxHeightPx>][pageId]
     private val pageAutoCropRects = mutableListOf<RectF>()
     // Due to the way thumbnails render, the bottom right is more likely to be cut off
     private val autoCropSafetyMarginUpper = 2
     private val autoCropSafetyMarginLower = 16
 
+    private val numPages get() = if (usePdfBox) pdfDocument.numberOfPages else renderer.pageCount
+
     init {
-        val numPages = renderer.pageCount
         for (i in 0..<numPages) {
+            // PdfBox
+            val bBox = pdfDocument.getPage(i).bBox
+            boxPagePtWidths.add(bBox.width)
+            boxPagePtHeights.add(bBox.height)
+            // Android
             val page = renderer.openPage(i)
             pagePtWidths.add(page.width)
             pagePtHeights.add(page.height)
@@ -33,6 +48,7 @@ class PdfDocument(private val fileCached: File, private val autoCrop: Boolean =
         }
     }
 
+
     private val rectFIdentity = RectF(0F, 0F, 1F, 1F)
     private fun renderPage(index: Int, maxWidth: Int, maxHeight: Int, crop: Boolean = false): Bitmap {
         val cropRect = if (!crop || pageAutoCropRects.size <= index) rectFIdentity else pageAutoCropRects[index]
@@ -42,9 +58,14 @@ class PdfDocument(private val fileCached: File, private val autoCrop: Boolean =
         val heightFromMaxWidth = (ptHeight * maxWidth/ptWidth).toInt()
         val (width, height) = if (widthFromMaxHeight > maxWidth) Pair(maxWidth, heightFromMaxWidth) else Pair(widthFromMaxHeight, maxHeight)
 
+        val bitmap: Bitmap
+        if (usePdfBox) {
+            val scale = width / ptWidth
+            bitmap = boxRenderer.renderImage(index, scale)
+        } else {
             val page = renderer.openPage(index)
             println("Creating page $index bitmap with width $width and height $height from cropRect $cropRect")
-        val bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888)
+            bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888)
             val ptToPixel = height / ptHeight
             val transform = Matrix()
             val transposePtX = -cropRect.left * ptWidth
@@ -52,12 +73,12 @@ class PdfDocument(private val fileCached: File, private val autoCrop: Boolean =
             transform.setValues(floatArrayOf(ptToPixel, 0F, transposePtX * ptToPixel, 0F, ptToPixel, transposePtY * ptToPixel, 0F, 0F, 1F))
             page.render(bitmap, null, transform, PdfRenderer.Page.RENDER_MODE_FOR_DISPLAY)
             page.close()
+        }
         return bitmap
     }
 
     private fun renderPagesToMap(map: MutableMap<Int, Bitmap>, width: Int, height: Int, crop: Boolean = false, overwrite: Boolean = true) {
         if (overwrite) map.clear()
-        val numPages = renderer.pageCount
         for (i in 0..<numPages) {
             map.computeIfAbsent(i) { renderPage(i, width, height, crop) }
         }
@@ -72,7 +93,6 @@ class PdfDocument(private val fileCached: File, private val autoCrop: Boolean =
         println("Thumbnails rendered")
         if (autoCrop) {
             println("Auto cropping from thumbnails")
-            val numPages = renderer.pageCount
             pageAutoCropRects.clear()
             for (i in 0..<numPages) {
                 println("Auto cropping page $i from thumbnail")

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

@@ -22,39 +22,4 @@
 
     <include android:id="@+id/content_main" layout="@layout/content_main" />
 
-    <com.google.android.material.floatingactionbutton.FloatingActionButton
-        android:id="@+id/crop"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:layout_gravity="bottom|end"
-        android:layout_marginEnd="@dimen/fab_margin"
-        android:layout_marginBottom="16dp"
-        android:importantForAccessibility="no"
-        app:maxImageSize="48dp"
-        app:srcCompat="@android:drawable/ic_menu_crop" />
-
-    <com.google.android.material.floatingactionbutton.FloatingActionButton
-        android:id="@+id/zoom_in"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:layout_gravity="bottom|start"
-        android:layout_marginStart="96dp"
-        android:layout_marginBottom="16dp"
-        android:importantForAccessibility="no"
-        app:maxImageSize="48dp"
-        app:srcCompat="@android:drawable/ic_menu_zoom" />
-
-    <com.google.android.material.floatingactionbutton.FloatingActionButton
-        android:id="@+id/zoom_out"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:layout_gravity="bottom|start"
-        android:layout_marginStart="16dp"
-        android:layout_marginBottom="16dp"
-        android:importantForAccessibility="no"
-        android:rotationY="180"
-        android:rotationX="180"
-        app:maxImageSize="48dp"
-        app:srcCompat="@android:drawable/ic_menu_zoom" />
-
 </androidx.coordinatorlayout.widget.CoordinatorLayout>

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

@@ -18,16 +18,16 @@
         app:layout_constraintTop_toTopOf="parent"
         app:navGraph="@navigation/mobile_navigation" />
 
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="vertical">
+
         <HorizontalScrollView
             android:id="@+id/thumbnails_disabled_scroll"
-        android:layout_width="0dp"
+            android:layout_width="match_parent"
             android:layout_height="300dp"
-        android:background="#80C01010"
+            android:background="#80C01010">
-        app:layout_constraintBottom_toBottomOf="parent"
-        app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent"
-        app:layout_constraintVertical_bias="0.0">
 
             <LinearLayout
                 android:id="@+id/thumbnails_disabled_layout"
@@ -39,13 +39,9 @@
 
         <HorizontalScrollView
             android:id="@+id/thumbnails_scroll"
-        android:layout_width="0dp"
+            android:layout_width="match_parent"
             android:layout_height="0dp"
-        android:layout_marginTop="300dp"
+            android:layout_weight="3">
-        app:layout_constraintBottom_toBottomOf="parent"
-        app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent">
 
             <LinearLayout
                 android:id="@+id/thumbnails_layout"
@@ -60,12 +56,119 @@
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginStart="8dp"
-        android:layout_marginTop="308dp"
             android:layout_marginEnd="8dp"
             android:textAlignment="center"
-        android:textSize="20sp"
+            android:textSize="20sp" />
-        app:layout_constraintBottom_toBottomOf="parent"
+
-        app:layout_constraintEnd_toEndOf="parent"
+        <com.google.android.material.chip.ChipGroup
-        app:layout_constraintStart_toStartOf="parent"
+            android:id="@+id/chip_group_pages"
-        app:layout_constraintTop_toTopOf="parent" />
+            app:singleSelection="true"
+            app:selectionRequired="true"
+            android:layout_width="match_parent"
+            android:layout_height="0dp"
+            android:layout_weight="1">
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_pages_1"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="1 page" />
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_pages_1.5"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="1.5 pages" />
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_pages_2"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="2 pages" />
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_pages_2.5"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="2.5 pages" />
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_pages_3"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:checked="true"
+                android:text="3 pages" />
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_pages_3.5"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="3.5 pages" />
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_pages_4"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="4 pages" />
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_pages_5"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="5 pages" />
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_pages_6"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="6 pages" />
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_pages_8"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="8 pages" />
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_pages_10"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="10 pages" />
+        </com.google.android.material.chip.ChipGroup>
+
+        <com.google.android.material.chip.ChipGroup
+            android:id="@+id/chip_group_toggles"
+            android:layout_width="match_parent"
+            android:layout_height="0dp"
+            android:layout_weight="1">
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_auto_crop"
+                android:checkable="true"
+                android:checked="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="Auto Crop" />
+
+            <com.google.android.material.chip.Chip
+                android:id="@+id/chip_use_pdf_box"
+                android:checkable="true"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="Use PdfBox renderer (slower)" />
+        </com.google.android.material.chip.ChipGroup>
+
+    </LinearLayout>
+
 </androidx.constraintlayout.widget.ConstraintLayout>

gradle/libs.versions.toml

@@ -12,6 +12,7 @@ lifecycleLivedataKtx = "2.8.4"
 lifecycleViewmodelKtx = "2.8.4"
 navigationFragmentKtx = "2.7.7"
 navigationUiKtx = "2.7.7"
+pdfboxAndroid = "2.0.27.0"
 
 [libraries]
 androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
@@ -25,6 +26,7 @@ androidx-lifecycle-livedata-ktx = { group = "androidx.lifecycle", name = "lifecy
 androidx-lifecycle-viewmodel-ktx = { group = "androidx.lifecycle", name = "lifecycle-viewmodel-ktx", version.ref = "lifecycleViewmodelKtx" }
 androidx-navigation-fragment-ktx = { group = "androidx.navigation", name = "navigation-fragment-ktx", version.ref = "navigationFragmentKtx" }
 androidx-navigation-ui-ktx = { group = "androidx.navigation", name = "navigation-ui-ktx", version.ref = "navigationUiKtx" }
+pdfbox-android = { module = "com.tom-roush:pdfbox-android", version.ref = "pdfboxAndroid" }
 
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }