Refactor control view to the template's GalleryFragment

If this works out, it will eventually be renamed appropriately

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

@@ -13,6 +13,7 @@ import android.view.WindowManager
 import android.widget.ImageView
 import androidx.activity.SystemBarStyle
 import androidx.activity.enableEdgeToEdge
+import androidx.activity.viewModels
 import com.google.android.material.snackbar.Snackbar
 import com.google.android.material.navigation.NavigationView
 import androidx.navigation.findNavController
@@ -26,6 +27,7 @@ import androidx.core.view.WindowCompat
 import androidx.core.view.WindowInsetsCompat
 import com.google.android.material.chip.Chip
 import com.lhw.pdf.databinding.ActivityMainBinding
+import com.lhw.pdf.ui.gallery.GalleryViewModel
 import com.tom_roush.pdfbox.android.PDFBoxResourceLoader
 import java.io.File
 import java.io.FileOutputStream
@@ -34,6 +36,7 @@ import kotlin.math.max
 import kotlin.math.min
 
 class MainActivity : AppCompatActivity() {
+    private val viewModel: GalleryViewModel by viewModels()
     private lateinit var appBarConfiguration: AppBarConfiguration
     private lateinit var binding: ActivityMainBinding
     private lateinit var displayManager: DisplayManager
@@ -46,7 +49,6 @@ class MainActivity : AppCompatActivity() {
     private val presentations = mutableMapOf<Int, MyPresentation>()
     private lateinit var pdfDocument: PdfDocument
     private val showPages = mutableListOf<Boolean>()
-    private val thumbnailImageViews = mutableListOf<ImageView>()
     private val defaultCachedFileName = "cached.pdf"
 
     private fun setPagesPerLandscape(pages: Float) {
@@ -118,35 +120,7 @@ class MainActivity : AppCompatActivity() {
         presentation.show()
     }
 
-    private fun reLayoutThumbnails() {
-        val container = binding.appBarMain.contentMain.thumbnailsLayout
-        val disabledContainer = binding.appBarMain.contentMain.thumbnailsDisabledLayout
-        container.removeAllViewsInLayout()
-        disabledContainer.removeAllViewsInLayout()
-        showPages.map { if (it) container else disabledContainer }.zip(thumbnailImageViews).forEach { (cont, img) ->
-            cont.addView(img)
-        }
-        updatePresentations(false)
-    }
-
-    private fun populateThumbnails() {
-        showPages.clear()
-        for ((index, bitmap) in pdfDocument.bitmapThumbnails) {
-            val img = ImageView(this)
-            img.setImageBitmap(bitmap)
-            img.setOnClickListener {
-                showPages[index] = !showPages[index]
-                //img.setColorFilter(if (showPages[index]) 0 else 0x7F000000, PorterDuff.Mode.DARKEN)
-                reLayoutThumbnails()
-            }
-            thumbnailImageViews.add(img)
-            showPages.add(true)
-        }
-        reLayoutThumbnails()
-    }
-
     private fun updateDisplayText() {
-        val displayText = binding.appBarMain.contentMain.textDisplays
         val text = StringBuilder()
 
         displayManager.displays.forEach {
@@ -159,7 +133,7 @@ class MainActivity : AppCompatActivity() {
             text.append("\n")
         }
         text.append(presentations)
-        displayText.text = text.toString()
+        viewModel.textDisplays.value = text.toString()
     }
 
     override fun onSaveInstanceState(outState: Bundle) {
@@ -180,6 +154,11 @@ class MainActivity : AppCompatActivity() {
         //val windowInsetsController = WindowCompat.getInsetsController(window, window.decorView)
         //windowInsetsController.hide(WindowInsetsCompat.Type.systemBars())  //Doesn't seem to actually fill the vacant space by default
 
+        savedInstanceState?.getFloat("thumbnailScrollProgress")?.let { viewModel.thumbnailScrollProgress.value = it }
+        savedInstanceState?.getFloat("pagesPerLandscape")?.let { pagesPerLandscape = it }
+        renderAutoCrop = savedInstanceState?.getBoolean("renderAutoCrop") ?: true
+        val lastFileName = savedInstanceState?.getString("fileName")  // TODO: proper filenames
+
         PDFBoxResourceLoader.init(this)
 
         binding = ActivityMainBinding.inflate(layoutInflater)
@@ -190,7 +169,6 @@ class MainActivity : AppCompatActivity() {
         setSupportActionBar(binding.appBarMain.toolbar)
 
         // Load previous pdf, or included test pdf first
-        val lastFileName = savedInstanceState?.getString("fileName")  // TODO: proper filenames
         var file = File(cacheDir, defaultCachedFileName)
         if (!file.exists()) {
             file = inputStreamToCache(defaultCachedFileName, resources.openRawResource(R.raw.testpdf))
@@ -199,45 +177,40 @@ class MainActivity : AppCompatActivity() {
         // Then overwrite it with any pdf sent via intent
         handleIntent(intent)
 
-        renderAutoCrop = savedInstanceState?.getBoolean("renderAutoCrop") ?: true
 
         pdfDocument.renderThumbnails(thumbnailWidth, thumbnailHeight)
         displayManager.getDisplays(DisplayManager.DISPLAY_CATEGORY_PRESENTATION).forEach(::makePresentationView)
-        populateThumbnails()  // Populates showPages
+
+        val bitmaps = pdfDocument.bitmapThumbnails.toSortedMap().values.toList()
+        showPages.clear()
+        bitmaps.forEach { _ -> showPages.add(true) }
         savedInstanceState?.getBooleanArray("showPages")?.forEachIndexed { i, show ->
             showPages[i] = show
         }
-        reLayoutThumbnails()
+        viewModel.showPages.value = showPages.toList()
+        viewModel.pageThumbnails.value = bitmaps
 
-        val container = binding.appBarMain.contentMain.thumbnailsLayout
-        val containerScroll = binding.appBarMain.contentMain.thumbnailsScroll
-        containerScroll.viewTreeObserver.addOnScrollChangedListener {
-            thumbnailScrollProgress = containerScroll.scrollX.toFloat() / (container.width - containerScroll.width)
-            presentations.values.forEach {it.setScrollProgress(thumbnailScrollProgress)}
-        }
-        savedInstanceState?.getFloat("thumbnailScrollProgress")?.let { thumbnailScrollProgress = it }
-        containerScroll.scrollTo((thumbnailScrollProgress * (container.width - containerScroll.width)).toInt(), 0)
 
-        savedInstanceState?.getFloat("pagesPerLandscape")?.let { pagesPerLandscape = it }
+        viewModel.pagesPerLandscape.observe(this) {
-        val pageZoomLevels = arrayOf(1F, 1.5F, 2F, 2.5F, 3F, 3.5F, 4F, 5F, 6F, 8F, 10F)
+            setPagesPerLandscape(it)
-        val chipGroupPages = binding.appBarMain.contentMain.chipGroupPages
-        pageZoomLevels.forEach { pages ->
-            val chip = Chip(this)
-            chip.text = "$pages pages"
-            chip.isCheckable = true
-            chip.isChecked = (pages == pagesPerLandscape)
-            chip.setOnCheckedChangeListener { _, checked -> if (checked) setPagesPerLandscape(pages) }
-            chipGroupPages.addView(chip)
         }
-        binding.appBarMain.contentMain.chipAutoCrop.setOnCheckedChangeListener { _, checked ->
+        viewModel.renderAutoCrop.observe(this) {
-            renderAutoCrop = checked
+            renderAutoCrop = it
             updatePresentations()
         }
-        binding.appBarMain.contentMain.chipUsePdfBox.setOnCheckedChangeListener { _, checked ->
+        viewModel.usePdfBox.observe(this) {
-            usePdfBox = checked
+            usePdfBox = it
             pdfDocument.usePdfBox = usePdfBox
             updatePresentations()
         }
+        viewModel.showPages.observe(this) {
+            it.forEachIndexed() {i, shown -> showPages[i] = shown}
+            updatePresentations(false)
+        }
+        viewModel.thumbnailScrollProgress.observe(this) { thumbnailScrollProgress ->
+            presentations.values.forEach {it.setScrollProgress(thumbnailScrollProgress)}
+        }
+
         val drawerLayout: DrawerLayout = binding.drawerLayout
         val navView: NavigationView = binding.navView
         val navController = findNavController(R.id.nav_host_fragment_content_main)

app/src/main/java/com/lhw/pdf/ui/gallery/GalleryFragment.kt

@@ -1,36 +1,70 @@
 package com.lhw.pdf.ui.gallery
 
+import android.graphics.Bitmap
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
+import android.widget.ImageView
 import android.widget.TextView
 import androidx.fragment.app.Fragment
+import androidx.fragment.app.activityViewModels
 import androidx.lifecycle.ViewModelProvider
+import com.google.android.material.chip.Chip
 import com.lhw.pdf.databinding.FragmentGalleryBinding
 
 class GalleryFragment : Fragment() {
-
+    private val galleryViewModel: GalleryViewModel by activityViewModels()
     private var _binding: FragmentGalleryBinding? = null
 
     // This property is only valid between onCreateView and
     // onDestroyView.
     private val binding get() = _binding!!
 
+    private val pageZoomLevels = arrayOf(1F, 1.5F, 2F, 2.5F, 3F, 3.5F, 4F, 5F, 6F, 8F, 10F)
+    private val pageZoomLevelChips = mutableMapOf<Float, Chip>()
+    private val thumbnailImageViews = mutableListOf<ImageView>()
+
     override fun onCreateView(
         inflater: LayoutInflater,
         container: ViewGroup?,
         savedInstanceState: Bundle?
     ): View {
-        val galleryViewModel =
+//        val galleryViewModel = ViewModelProvider(this)[GalleryViewModel::class.java]
-            ViewModelProvider(this)[GalleryViewModel::class.java]
 
         _binding = FragmentGalleryBinding.inflate(inflater, container, false)
         val root: View = binding.root
 
-        val textView: TextView = binding.textGallery
+        val chipGroupPages = binding.chipGroupPages
-        galleryViewModel.text.observe(viewLifecycleOwner) {
+        pageZoomLevels.forEach { pages ->
-            textView.text = it
+            val chip = Chip(context)
+            chip.text = "$pages pages"
+            chip.isCheckable = true
+            chip.setOnCheckedChangeListener { _, checked -> if (checked) galleryViewModel.pagesPerLandscape.value = pages }
+            chipGroupPages.addView(chip)
+            pageZoomLevelChips[pages] = chip
+        }
+        pageZoomLevelChips[galleryViewModel.pagesPerLandscape.value]?.isChecked = true
+        binding.chipAutoCrop.isChecked = galleryViewModel.renderAutoCrop.value!!
+        binding.chipUsePdfBox.isChecked = galleryViewModel.usePdfBox.value!!
+
+        galleryViewModel.textDisplays.observe(viewLifecycleOwner) { binding.textDisplays.text = it }
+        galleryViewModel.usePdfBox.observe(viewLifecycleOwner) { binding.chipUsePdfBox.isChecked = it }
+        galleryViewModel.renderAutoCrop.observe(viewLifecycleOwner) { binding.chipAutoCrop.isChecked = it }
+        galleryViewModel.pagesPerLandscape.observe(viewLifecycleOwner) {
+            pageZoomLevelChips[it]?.isChecked = true
+        }
+
+        binding.chipAutoCrop.setOnCheckedChangeListener { _, checked -> galleryViewModel.renderAutoCrop.value = checked }
+        binding.chipUsePdfBox.setOnCheckedChangeListener { _, checked -> galleryViewModel.usePdfBox.value = checked }
+
+        galleryViewModel.pageThumbnails.observe(viewLifecycleOwner, ::populateThumbnails)
+
+        val container = binding.thumbnailsLayout
+        val containerScroll = binding.thumbnailsScroll
+        containerScroll.scrollTo(((galleryViewModel.thumbnailScrollProgress.value ?: 0F) * (container.width - containerScroll.width)).toInt(), 0)
+        containerScroll.viewTreeObserver.addOnScrollChangedListener {
+            galleryViewModel.thumbnailScrollProgress.value = containerScroll.scrollX.toFloat() / (container.width - containerScroll.width)
         }
         return root
     }
@@ -39,4 +73,31 @@ class GalleryFragment : Fragment() {
         super.onDestroyView()
         _binding = null
     }
+
+    private fun reLayoutThumbnails() {
+        val container = binding.thumbnailsLayout
+        val disabledContainer = binding.thumbnailsDisabledLayout
+        container.removeAllViewsInLayout()
+        disabledContainer.removeAllViewsInLayout()
+        galleryViewModel.showPages.value
+            ?.map { if (it) container else disabledContainer }
+            ?.zip(thumbnailImageViews)?.forEach { (cont, img) ->
+                cont.addView(img)
+        }
+    }
+
+    private fun populateThumbnails(bitmaps: List<Bitmap>) {
+        bitmaps.forEachIndexed() { index, bitmap ->
+            val img = ImageView(context)
+            img.setImageBitmap(bitmap)
+            img.setOnClickListener {
+                val showPages = galleryViewModel.showPages.value!!.toMutableList()
+                showPages[index] = !showPages[index]
+                galleryViewModel.showPages.value = showPages.toList()
+                reLayoutThumbnails()
+            }
+            thumbnailImageViews.add(img)
+        }
+        reLayoutThumbnails()
+    }
 }

app/src/main/java/com/lhw/pdf/ui/gallery/GalleryViewModel.kt

@@ -1,13 +1,16 @@
 package com.lhw.pdf.ui.gallery
 
+import android.graphics.Bitmap
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
 
 class GalleryViewModel : ViewModel() {
-
+    val pageThumbnails = MutableLiveData<List<Bitmap>>().apply { value = listOf() }
-    private val _text = MutableLiveData<String>().apply {
+    val showPages = MutableLiveData<List<Boolean>>().apply { value = listOf() }
-        value = "This is gallery Fragment"
+    val thumbnailScrollProgress = MutableLiveData<Float>().apply { value = 0F }
-    }
+    val textDisplays = MutableLiveData<String>().apply { value = "" }
-    val text: LiveData<String> = _text
+    val pagesPerLandscape = MutableLiveData<Float>().apply { value = 3F }
+    val renderAutoCrop = MutableLiveData<Boolean>().apply { value = true }
+    val usePdfBox = MutableLiveData<Boolean>().apply { value = false }
 }

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

@@ -18,79 +18,4 @@
         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="match_parent"
-            android:layout_height="300dp"
-            android:background="#80C01010">
-
-            <LinearLayout
-                android:id="@+id/thumbnails_disabled_layout"
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:orientation="horizontal"
-                tools:showIn="@layout/content_main" />
-        </HorizontalScrollView>
-
-        <HorizontalScrollView
-            android:id="@+id/thumbnails_scroll"
-            android:layout_width="match_parent"
-            android:layout_height="0dp"
-            android:layout_weight="3">
-
-            <LinearLayout
-                android:id="@+id/thumbnails_layout"
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:orientation="horizontal"
-                tools:showIn="@layout/content_main" />
-        </HorizontalScrollView>
-
-        <TextView
-            android:id="@+id/text_displays"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:layout_marginStart="8dp"
-            android:layout_marginEnd="8dp"
-            android:textAlignment="center"
-            android:textSize="20sp" />
-
-        <com.google.android.material.chip.ChipGroup
-            android:id="@+id/chip_group_pages"
-            app:singleSelection="true"
-            app:selectionRequired="true"
-            android:layout_width="match_parent"
-            android:layout_height="0dp"
-            android:layout_weight="1">
-        </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>

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

@@ -6,17 +6,78 @@
     android:layout_height="match_parent"
     tools:context=".ui.gallery.GalleryFragment">
 
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="vertical">
+
+        <HorizontalScrollView
+            android:id="@+id/thumbnails_disabled_scroll"
+            android:layout_width="match_parent"
+            android:layout_height="300dp"
+            android:background="#80C01010">
+
+            <LinearLayout
+                android:id="@+id/thumbnails_disabled_layout"
+                android:layout_width="wrap_content"
+                android:layout_height="match_parent"
+                android:orientation="horizontal"
+                tools:showIn="@layout/content_main" />
+        </HorizontalScrollView>
+
+        <HorizontalScrollView
+            android:id="@+id/thumbnails_scroll"
+            android:layout_width="match_parent"
+            android:layout_height="0dp"
+            android:layout_weight="3">
+
+            <LinearLayout
+                android:id="@+id/thumbnails_layout"
+                android:layout_width="wrap_content"
+                android:layout_height="match_parent"
+                android:orientation="horizontal"
+                tools:showIn="@layout/content_main" />
+        </HorizontalScrollView>
+
         <TextView
-        android:id="@+id/text_gallery"
+            android:id="@+id/text_displays"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginStart="8dp"
-        android:layout_marginTop="8dp"
             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.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>