FileCannotOpenDialogFragment should not be cancelable

src/main/java/com/kdanmobile/reader/copyfile/CopyFileActivity.kt

@@ -62,6 +62,7 @@ abstract class CopyFileActivity : KdanBaseActivity() {
         fileCannotOpenDialog.arguments = Bundle().also {
             it.putString(FileCannotOpenDialogFragment.KEY_DIALOG_TITLE, title)
         }
+        fileCannotOpenDialog.isCancelable = false
         fileCannotOpenDialog.show(supportFragmentManager, fileCannotOpenDialog.tag)
     }
 

src/main/java/com/kdanmobile/reader/copyfile/FileCannotOpenDialogFragment.kt

@@ -15,7 +15,6 @@ class FileCannotOpenDialogFragment : DialogFragment() {
 
         return AlertDialog.Builder(activity!!)
                 .setTitle(arguments?.getString(KEY_DIALOG_TITLE))
-                .setCancelable(false)
                 .setPositiveButton(getString(android.R.string.ok)) { dialog, which ->
                     activity?.finish()
                 }