fixing some crashes

app/src/main/kotlin/com/simplemobiletools/gallery/pro/activities/MainActivity.kt

@@ -1122,7 +1122,10 @@ class MainActivity : SimpleActivity(), DirectoryOperationsListener {
             dirs.removeAll(invalidDirs)
             setupAdapter(dirs)
             invalidDirs.forEach {
-                mDirectoryDao.deleteDirPath(it.path)
+                try {
+                    mDirectoryDao.deleteDirPath(it.path)
+                } catch (ignored: Exception) {
+                }
             }
         }
     }

app/src/main/kotlin/com/simplemobiletools/gallery/pro/extensions/Context.kt

@@ -6,7 +6,6 @@ import android.content.Context
 import android.content.Intent
 import android.content.res.Configuration
 import android.database.Cursor
-import android.database.sqlite.SQLiteException
 import android.graphics.Point
 import android.graphics.drawable.PictureDrawable
 import android.media.AudioManager
@@ -477,7 +476,7 @@ fun Context.getCachedDirectories(getVideosOnly: Boolean = false, getImagesOnly:
     Thread {
         val directories = try {
             directoryDao.getAll() as ArrayList<Directory>
-        } catch (e: SQLiteException) {
+        } catch (e: Exception) {
             ArrayList<Directory>()
         }
 

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

@@ -243,11 +243,13 @@ class PhotoFragment : ViewPagerFragment() {
         // avoid GIFs being skewed, played in wrong aspect ratio
         if (mMedium.isGIF()) {
             mView.onGlobalLayout {
-                measureScreen()
-                Handler().postDelayed({
-                    mView.gif_view_frame.controller.resetState()
-                    loadGif()
-                }, 50)
+                if (activity != null) {
+                    measureScreen()
+                    Handler().postDelayed({
+                        mView.gif_view_frame.controller.resetState()
+                        loadGif()
+                    }, 50)
+                }
             }
         } else {
             hideZoomableView()
@@ -286,7 +288,7 @@ class PhotoFragment : ViewPagerFragment() {
 
     private fun measureScreen() {
         val metrics = DisplayMetrics()
-        activity!!.windowManager.defaultDisplay.getRealMetrics(metrics)
+        activity?.windowManager?.defaultDisplay?.getRealMetrics(metrics)
         mScreenWidth = metrics.widthPixels
         mScreenHeight = metrics.heightPixels
     }