some updates to starting slideshow from the thumbnails screen

app/src/main/kotlin/com/simplemobiletools/gallery/activities/MediaActivity.kt

@@ -249,9 +249,9 @@ class MediaActivity : SimpleActivity(), MediaOperationsListener {
             R.id.stop_showing_hidden -> tryToggleTemporarilyShowHidden()
             R.id.increase_column_count -> increaseColumnCount()
             R.id.reduce_column_count -> reduceColumnCount()
+            R.id.slideshow -> startSlideshow()
             R.id.settings -> launchSettings()
             R.id.about -> launchAbout()
-            R.id.slideshow -> startSlideshow()
             else -> return super.onOptionsItemSelected(item)
         }
         return true
@@ -260,10 +260,8 @@ class MediaActivity : SimpleActivity(), MediaOperationsListener {
     private fun startSlideshow() {
         if (mMedia.isNotEmpty()) {
             Intent(this, ViewPagerActivity::class.java).apply {
-                val item = mMedia[0]
+                val item = mMedia.firstOrNull { it is Medium } as? Medium ?: return
-                if (item is Medium) {
                 putExtra(PATH, item.path)
-                }
                 putExtra(SHOW_ALL, mShowAll)
                 putExtra(SLIDESHOW_START_ON_ENTER, true)
                 startActivity(this)

app/src/main/kotlin/com/simplemobiletools/gallery/activities/ViewPagerActivity.kt

@@ -53,8 +53,6 @@ import java.io.InputStream
 import java.io.OutputStream
 import java.util.*
 
-private val SLIDESHOW_INITED_ON_START_KEY = "SLIDESHOW_INITED_ON_START"
-
 class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, ViewPagerFragment.FragmentListener {
     private var mPath = ""
     private var mDirectory = ""
@@ -70,7 +68,6 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
     private var mSlideshowMoveBackwards = false
     private var mSlideshowMedia = mutableListOf<Medium>()
     private var mAreSlideShowMediaVisible = false
-    private var mSlideshowInitedOnStart = false
 
     private var mIsOrientationLocked = false
 
@@ -104,23 +101,6 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
         }
 
         initFavorites()
-        handleSlideshowRequest(savedInstanceState)
-    }
-
-    private fun handleSlideshowRequest(state: Bundle?) {
-        if (intent.getBooleanExtra(SLIDESHOW_START_ON_ENTER, false)) {
-            if (state == null || !state.getBoolean(SLIDESHOW_INITED_ON_START_KEY, false)) {
-                mSlideshowHandler.post {
-                    initSlideshow()
-                }
-            }
-            mSlideshowInitedOnStart = true
-        }
-    }
-
-    override fun onSaveInstanceState(outState: Bundle) {
-        super.onSaveInstanceState(outState)
-        outState.putBoolean(SLIDESHOW_INITED_ON_START_KEY, mSlideshowInitedOnStart)
     }
 
     override fun onResume() {
@@ -243,6 +223,7 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
             if (!isDestroyed) {
                 if (mMediaFiles.isNotEmpty()) {
                     gotMedia(mMediaFiles as ArrayList<ThumbnailItem>)
+                    checkSlideshowOnEnter()
                 }
             }
         }
@@ -268,6 +249,7 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
             } else {
                 visibility and View.SYSTEM_UI_FLAG_FULLSCREEN != 0
             }
+
             view_pager.adapter?.let {
                 (it as MyPagerAdapter).toggleFullscreen(mIsFullScreen)
                 checkSystemUI()
@@ -389,6 +371,12 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
         }
     }
 
+    private fun checkSlideshowOnEnter() {
+        if (intent.getBooleanExtra(SLIDESHOW_START_ON_ENTER, false)) {
+            initSlideshow()
+        }
+    }
+
     private fun initSlideshow() {
         SlideshowDialog(this) {
             startSlideshow()

app/src/main/res/menu/menu_media.xml

@@ -79,6 +79,10 @@
         android:id="@+id/reduce_column_count"
         android:title="@string/reduce_column_count"
         app:showAsAction="never"/>
+    <item
+        android:id="@+id/slideshow"
+        android:title="@string/slideshow"
+        app:showAsAction="never"/>
     <item
         android:id="@+id/settings"
         android:title="@string/settings"
@@ -87,8 +91,4 @@
         android:id="@+id/about"
         android:title="@string/about"
         app:showAsAction="never"/>
-    <item
-        android:id="@+id/slideshow"
-        android:title="@string/slideshow"
-        app:showAsAction="never"/>
 </menu>