diff --git a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/EditActivity.kt b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/EditActivity.kt
index 26cea909e..8a082817f 100644
--- a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/EditActivity.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/EditActivity.kt
@@ -808,7 +808,7 @@ class EditActivity : SimpleActivity(), CropImageView.OnCropImageCompleteListener
         if (newPath.isEmpty()) {
             val filename = applicationContext.getFilenameFromContentUri(saveUri) ?: ""
             if (filename.isNotEmpty()) {
-                val path = if (intent.extras?.containsKey(REAL_FILE_PATH) == true) intent.getStringExtra(REAL_FILE_PATH).getParentPath() else internalStoragePath
+                val path = if (intent.extras?.containsKey(REAL_FILE_PATH) == true) intent.getStringExtra(REAL_FILE_PATH)?.getParentPath() else internalStoragePath
                 newPath = "$path/$filename"
                 shouldAppendFilename = false
             }
diff --git a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/MediaActivity.kt b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/MediaActivity.kt
index 731ac3e6d..48395d4f0 100644
--- a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/MediaActivity.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/MediaActivity.kt
@@ -97,7 +97,7 @@ class MediaActivity : SimpleActivity(), MediaOperationsListener {
 
         media_refresh_layout.setOnRefreshListener { getMedia() }
         try {
-            mPath = intent.getStringExtra(DIRECTORY)
+            mPath = intent.getStringExtra(DIRECTORY) ?: ""
         } catch (e: Exception) {
             showErrorToast(e)
             finish()
diff --git a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/SimpleActivity.kt b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/SimpleActivity.kt
index 6824b7038..66abce29d 100644
--- a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/SimpleActivity.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/SimpleActivity.kt
@@ -20,13 +20,15 @@ import com.simplemobiletools.gallery.pro.extensions.updateDirectoryPath
 
 open class SimpleActivity : BaseSimpleActivity() {
     val observer = object : ContentObserver(null) {
-        override fun onChange(selfChange: Boolean, uri: Uri) {
+        override fun onChange(selfChange: Boolean, uri: Uri?) {
             super.onChange(selfChange, uri)
-            val path = getRealPathFromURI(uri)
-            if (path != null) {
-                updateDirectoryPath(path.getParentPath())
-                addPathToDB(path)
-            }
+	    if (uri != null) {
+            	val path = getRealPathFromURI(uri)
+            	if (path != null) {
+            	    updateDirectoryPath(path.getParentPath())
+            	    addPathToDB(path)
+            	}
+	    }
         }
     }
 
diff --git a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/VideoPlayerActivity.kt b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/VideoPlayerActivity.kt
index b1c319a1e..879f5bd4f 100644
--- a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/VideoPlayerActivity.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/VideoPlayerActivity.kt
@@ -618,16 +618,16 @@ open class VideoPlayerActivity : SimpleActivity(), SeekBar.OnSeekBarChangeListen
         mIsDragged = false
     }
 
-    override fun onSurfaceTextureUpdated(surface: SurfaceTexture?) {
+    override fun onSurfaceTextureUpdated(surface: SurfaceTexture) {
     }
 
-    override fun onSurfaceTextureDestroyed(surface: SurfaceTexture?) = false
+    override fun onSurfaceTextureDestroyed(surface: SurfaceTexture) = false
 
-    override fun onSurfaceTextureAvailable(surface: SurfaceTexture?, width: Int, height: Int) {
+    override fun onSurfaceTextureAvailable(surface: SurfaceTexture, width: Int, height: Int) {
         ensureBackgroundThread {
             mExoPlayer?.setVideoSurface(Surface(video_surface!!.surfaceTexture))
         }
     }
 
-    override fun onSurfaceTextureSizeChanged(surface: SurfaceTexture?, width: Int, height: Int) {}
+    override fun onSurfaceTextureSizeChanged(surface: SurfaceTexture, width: Int, height: Int) {}
 }
diff --git a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/ViewPagerActivity.kt b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/ViewPagerActivity.kt
index 264133ecd..37fc55029 100644
--- a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/ViewPagerActivity.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/ViewPagerActivity.kt
@@ -272,7 +272,7 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
             }
         } else {
             try {
-                mPath = intent.getStringExtra(PATH)
+                mPath = intent.getStringExtra(PATH) ?: ""
                 mShowAll = config.showAll
             } catch (e: Exception) {
                 showErrorToast(e)
diff --git a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/fragments/VideoFragment.kt b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/fragments/VideoFragment.kt
index 35c1b8913..bf68ff8cf 100644
--- a/app/src/main/kotlin/com/simplemobiletools/gallery/pro/fragments/VideoFragment.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/gallery/pro/fragments/VideoFragment.kt
@@ -759,13 +759,13 @@ class VideoFragment : ViewPagerFragment(), TextureView.SurfaceTextureListener, S
         }
     }
 
-    override fun onSurfaceTextureSizeChanged(surface: SurfaceTexture?, width: Int, height: Int) {}
+    override fun onSurfaceTextureSizeChanged(surface: SurfaceTexture, width: Int, height: Int) {}
 
-    override fun onSurfaceTextureUpdated(surface: SurfaceTexture?) {}
+    override fun onSurfaceTextureUpdated(surface: SurfaceTexture) {}
 
-    override fun onSurfaceTextureDestroyed(surface: SurfaceTexture?) = false
+    override fun onSurfaceTextureDestroyed(surface: SurfaceTexture) = false
 
-    override fun onSurfaceTextureAvailable(surface: SurfaceTexture?, width: Int, height: Int) {
+    override fun onSurfaceTextureAvailable(surface: SurfaceTexture, width: Int, height: Int) {
         ensureBackgroundThread {
             mExoPlayer?.setVideoSurface(Surface(mTextureView.surfaceTexture))
         }