store the screen resolution at view pager activity

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

@@ -2,6 +2,7 @@ package com.simplemobiletools.gallery.activities
 
 import android.app.Activity
 import android.content.Intent
+import android.content.res.Configuration
 import android.database.Cursor
 import android.graphics.Bitmap
 import android.graphics.BitmapFactory
@@ -12,6 +13,7 @@ import android.os.Build
 import android.os.Bundle
 import android.provider.MediaStore
 import android.support.v4.view.ViewPager
+import android.util.DisplayMetrics
 import android.view.Menu
 import android.view.MenuItem
 import android.view.View
@@ -49,6 +51,11 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
     private var mShowAll = false
     private var mRotationDegrees = 0f
 
+    companion object {
+        var screenWidth = 0
+        var screenHeight = 0
+    }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_medium)
@@ -58,6 +65,7 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
             return
         }
 
+        measureScreen()
         val uri = intent.data
         if (uri != null) {
             var cursor: Cursor? = null
@@ -156,6 +164,18 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
         return true
     }
 
+    override fun onConfigurationChanged(newConfig: Configuration?) {
+        super.onConfigurationChanged(newConfig)
+        measureScreen()
+    }
+
+    private fun measureScreen() {
+        val metrics = DisplayMetrics()
+        windowManager.defaultDisplay.getMetrics(metrics)
+        screenWidth = metrics.widthPixels
+        screenHeight = metrics.heightPixels
+    }
+
     private fun updatePagerItems() {
         val pagerAdapter = MyPagerAdapter(this, supportFragmentManager, mMedia)
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1 && !isDestroyed) {

app/src/main/kotlin/com/simplemobiletools/gallery/fragments/PhotoFragment.kt

@@ -6,7 +6,6 @@ import android.graphics.BitmapFactory
 import android.graphics.Matrix
 import android.net.Uri
 import android.os.Bundle
-import android.util.DisplayMetrics
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
@@ -16,6 +15,7 @@ import com.simplemobiletools.commons.extensions.beGone
 import com.simplemobiletools.commons.extensions.beVisible
 import com.simplemobiletools.commons.extensions.toast
 import com.simplemobiletools.gallery.R
+import com.simplemobiletools.gallery.activities.ViewPagerActivity
 import com.simplemobiletools.gallery.extensions.getRealPathFromURI
 import com.simplemobiletools.gallery.helpers.MEDIUM
 import com.simplemobiletools.gallery.models.Medium
@@ -132,11 +132,9 @@ class PhotoFragment : ViewPagerFragment() {
     }
 
     private fun loadBitmap(degrees: Float = 0f) {
-        val metrics = DisplayMetrics()
-        activity.windowManager.defaultDisplay.getMetrics(metrics)
         Picasso.with(activity)
                 .load("file:${medium.path}")
-                .resize(metrics.widthPixels * 2, metrics.heightPixels * 2)
+                .resize(ViewPagerActivity.screenWidth * 2, ViewPagerActivity.screenHeight * 2)
                 .rotate(degrees)
                 .centerInside()
                 .into(view.photo_view)