diff --git a/app/src/main/java/com/lhw/pdf/MainActivity.kt b/app/src/main/java/com/lhw/pdf/MainActivity.kt
index 5eaf5f2..7c13b6b 100644
--- a/app/src/main/java/com/lhw/pdf/MainActivity.kt
+++ b/app/src/main/java/com/lhw/pdf/MainActivity.kt
@@ -122,7 +122,7 @@ class MainActivity : AppCompatActivity() {
 
         initializePdfDocument()
         pdfDocument.renderThumbnails(thumbnailWidth, thumbnailHeight)
-        val container = findViewById<LinearLayout>(R.id.thumbnails_layout)
+        val container = binding.appBarMain.contentMain.thumbnailsLayout
         for (bitmap in pdfDocument.bitmapThumbnails.values) {
             val img = ImageView(this)
             img.setImageBitmap(bitmap)
@@ -130,7 +130,7 @@ class MainActivity : AppCompatActivity() {
         }
         presentationView()
 
-        val containerScroll = findViewById<HorizontalScrollView>(R.id.thumbnails_scroll)
+        val containerScroll = binding.appBarMain.contentMain.thumbnailsScroll
         containerScroll.viewTreeObserver.addOnScrollChangedListener {
             presentationScroll.scrollTo(
                 containerScroll.scrollX * (presentationLayout.width - presentationScroll.width) / (container.width - containerScroll.width),
diff --git a/app/src/main/res/layout/app_bar_main.xml b/app/src/main/res/layout/app_bar_main.xml
index 0d4e98f..e1c24c3 100644
--- a/app/src/main/res/layout/app_bar_main.xml
+++ b/app/src/main/res/layout/app_bar_main.xml
@@ -20,7 +20,7 @@
 
     </com.google.android.material.appbar.AppBarLayout>
 
-    <include layout="@layout/content_main" />
+    <include android:id="@+id/content_main" layout="@layout/content_main" />
 
     <com.google.android.material.floatingactionbutton.FloatingActionButton
         android:id="@+id/fab"