Hide the reader seekbar for single-page chapters (#5551)

app/src/main/java/eu/kanade/tachiyomi/ui/reader/ReaderActivity.kt

@@ -29,6 +29,7 @@ import androidx.core.graphics.ColorUtils
 import androidx.core.view.WindowCompat
 import androidx.core.view.WindowInsetsCompat
 import androidx.core.view.WindowInsetsControllerCompat
+import androidx.core.view.isInvisible
 import androidx.core.view.isVisible
 import androidx.lifecycle.lifecycleScope
 import com.davemorrissey.labs.subscaleview.SubsamplingScaleImageView
@@ -603,6 +604,9 @@ class ReaderActivity : BaseRxActivity<ReaderActivityBinding, ReaderPresenter>()
         viewer?.setChapters(viewerChapters)
         binding.toolbar.subtitle = viewerChapters.currChapter.chapter.name
 
+        val currentChapterPageCount = viewerChapters.currChapter.pages?.size ?: 1
+        binding.readerSeekbar.isInvisible = currentChapterPageCount == 1
+
         val leftChapterObject = if (viewer is R2LPagerViewer) viewerChapters.nextChapter else viewerChapters.prevChapter
         val rightChapterObject = if (viewer is R2LPagerViewer) viewerChapters.prevChapter else viewerChapters.nextChapter