diff --git a/app/src/main/kotlin/com/simplemobiletools/gallery/Constants.kt b/app/src/main/kotlin/com/simplemobiletools/gallery/Constants.kt
index 162c93131..7edbb56d2 100644
--- a/app/src/main/kotlin/com/simplemobiletools/gallery/Constants.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/gallery/Constants.kt
@@ -31,3 +31,6 @@ object Constants {
     val GET_ANY_INTENT = "get_any_intent"
     val SET_WALLPAPER_INTENT = "set_wallpaper_intent"
 }
+
+val REQUEST_EDIT_IMAGE = 1
+val REQUEST_SET_WALLPAPER = 2
diff --git a/app/src/main/kotlin/com/simplemobiletools/gallery/activities/ViewPagerActivity.kt b/app/src/main/kotlin/com/simplemobiletools/gallery/activities/ViewPagerActivity.kt
index dda08bee0..1c1c5fe03 100644
--- a/app/src/main/kotlin/com/simplemobiletools/gallery/activities/ViewPagerActivity.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/gallery/activities/ViewPagerActivity.kt
@@ -11,18 +11,16 @@ import android.support.v4.view.ViewPager
 import android.view.Menu
 import android.view.MenuItem
 import android.view.View
-import android.webkit.MimeTypeMap
 import android.widget.RelativeLayout
 import com.simplemobiletools.filepicker.asynctasks.CopyMoveTask
 import com.simplemobiletools.filepicker.dialogs.ConfirmationDialog
 import com.simplemobiletools.filepicker.extensions.*
 import com.simplemobiletools.fileproperties.dialogs.PropertiesDialog
-import com.simplemobiletools.gallery.Constants
-import com.simplemobiletools.gallery.R
-import com.simplemobiletools.gallery.Utils
+import com.simplemobiletools.gallery.*
 import com.simplemobiletools.gallery.adapters.MyPagerAdapter
 import com.simplemobiletools.gallery.dialogs.CopyDialog
 import com.simplemobiletools.gallery.dialogs.RenameFileDialog
+import com.simplemobiletools.gallery.extensions.setAsWallpaper
 import com.simplemobiletools.gallery.extensions.shareMedium
 import com.simplemobiletools.gallery.fragments.ViewPagerFragment
 import com.simplemobiletools.gallery.models.Medium
@@ -42,11 +40,6 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
     private var mIsUndoShown = false
     private var mPos = 0
 
-    companion object {
-        private val EDIT_IMAGE = 1
-        private val SET_WALLPAPER = 2
-    }
-
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_medium)
@@ -130,7 +123,7 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
         deleteFile()
         return when (item.itemId) {
             R.id.menu_set_as_wallpaper -> {
-                setAsWallpaper()
+                setAsWallpaper(getCurrentFile())
                 true
             }
             R.id.menu_copy_move -> {
@@ -196,34 +189,12 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
         val chooser = Intent.createChooser(intent, getString(R.string.edit_image_with))
 
         if (intent.resolveActivity(packageManager) != null) {
-            startActivityForResult(chooser, EDIT_IMAGE)
+            startActivityForResult(chooser, REQUEST_EDIT_IMAGE)
         } else {
             toast(R.string.no_editor_found)
         }
     }
 
-    private fun getMimeType(url: String): String? {
-        val extension = MimeTypeMap.getFileExtensionFromUrl(url)
-        return if (extension != null) {
-            MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension)
-        } else {
-            "image/jpeg"
-        }
-    }
-
-    private fun setAsWallpaper() {
-        val intent = Intent(Intent.ACTION_ATTACH_DATA)
-        val uri = Uri.fromFile(getCurrentFile())
-        intent.setDataAndType(uri, getMimeType(uri.toString()))
-        val chooser = Intent.createChooser(intent, getString(R.string.set_as_wallpaper_with))
-
-        if (intent.resolveActivity(packageManager) != null) {
-            startActivityForResult(chooser, SET_WALLPAPER)
-        } else {
-            toast(R.string.no_wallpaper_setter_found)
-        }
-    }
-
     private fun openWith() {
         val intent = Intent(Intent.ACTION_VIEW)
         intent.setDataAndType(Uri.fromFile(getCurrentFile()), getCurrentMedium().getMimeType())
@@ -241,12 +212,12 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
     }
 
     override fun onActivityResult(requestCode: Int, resultCode: Int, resultData: Intent?) {
-        if (requestCode == EDIT_IMAGE) {
+        if (requestCode == REQUEST_EDIT_IMAGE) {
             if (resultCode == Activity.RESULT_OK && resultData != null) {
                 val adapter = view_pager.adapter as MyPagerAdapter
                 adapter.updateItems(mPos)
             }
-        } else if (requestCode == SET_WALLPAPER) {
+        } else if (requestCode == REQUEST_SET_WALLPAPER) {
             if (resultCode == Activity.RESULT_OK) {
                 toast(R.string.wallpaper_set_successfully)
             }
diff --git a/app/src/main/kotlin/com/simplemobiletools/gallery/extensions/activity.kt b/app/src/main/kotlin/com/simplemobiletools/gallery/extensions/activity.kt
index d61a9d903..bc8b61658 100644
--- a/app/src/main/kotlin/com/simplemobiletools/gallery/extensions/activity.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/gallery/extensions/activity.kt
@@ -3,7 +3,10 @@ package com.simplemobiletools.gallery.extensions
 import android.app.Activity
 import android.content.Intent
 import android.net.Uri
+import com.simplemobiletools.filepicker.extensions.getMimeType
+import com.simplemobiletools.filepicker.extensions.toast
 import com.simplemobiletools.gallery.R
+import com.simplemobiletools.gallery.REQUEST_SET_WALLPAPER
 import com.simplemobiletools.gallery.models.Medium
 import java.io.File
 import java.util.*
@@ -33,3 +36,18 @@ fun Activity.shareMedia(media: List<Medium>) {
         startActivity(Intent.createChooser(this, shareTitle))
     }
 }
+
+fun Activity.setAsWallpaper(file: File) {
+    val intent = Intent(Intent.ACTION_ATTACH_DATA)
+    val uri = Uri.fromFile(file)
+    var mimeType = getMimeType(uri.toString())
+    if (mimeType.isEmpty()) mimeType = "image/jpeg"
+    intent.setDataAndType(uri, mimeType)
+    val chooser = Intent.createChooser(intent, getString(R.string.set_as_wallpaper_with))
+
+    if (intent.resolveActivity(packageManager) != null) {
+        startActivityForResult(chooser, REQUEST_SET_WALLPAPER)
+    } else {
+        toast(R.string.no_wallpaper_setter_found)
+    }
+}