Minor refactoring

app/src/main/java/com/paktalin/vocabularynotebook/ui/MyItemDetailsLookup.kt

-package com.paktalin.vocabularynotebook.ui
-
-import android.view.MotionEvent
-import androidx.recyclerview.selection.ItemDetailsLookup
-import androidx.recyclerview.widget.RecyclerView
-
-class MyItemDetailsLookup(private val recyclerView: RecyclerView) :
-        ItemDetailsLookup<Long>() {
-    override fun getItemDetails(event: MotionEvent): ItemDetails<Long>? {
-        val view = recyclerView.findChildViewUnder(event.x, event.y)
-        if (view != null) {
-            return (recyclerView.getChildViewHolder(view) as ViewHolder)
-                    .getItemDetails()
-        }
-        return null
-    }
-}
\ No newline at end of file

app/src/main/java/com/paktalin/vocabularynotebook/ui/activities/MainActivity.kt

@@ -93,15 +93,7 @@ class MainActivity : AppCompatActivity() {
                     if (querySnapshot != null && !querySnapshot.isEmpty) {
                         vocabularyAdapter = VocabularyAdapter(VocabSet.createFromSnapshot(querySnapshot), this@MainActivity)
                         recyclerView.adapter = vocabularyAdapter
-                        tracker = SelectionTracker.Builder<Long>(
-                                "mySelection",
-                                recyclerView,
-                                StableIdKeyProvider(recyclerView),
-                                MyItemDetailsLookup(recyclerView),
-                                StorageStrategy.createLongStorage()
-                        ).withSelectionPredicate(
-                                SelectionPredicates.createSelectAnything()
-                        ).build()
+                        setSelectionTracker()
                         (recyclerView.adapter as VocabularyAdapter).tracker = tracker
 
                     } else showToastNoWords()
@@ -129,6 +121,18 @@ class MainActivity : AppCompatActivity() {
         shortToast(this, getString(R.string.toast_empty_vocabulary))
     }
 
+    private fun setSelectionTracker() {
+        tracker = SelectionTracker.Builder<Long>(
+                "mySelection",
+                recyclerView,
+                StableIdKeyProvider(recyclerView),
+                MyItemDetailsLookup(recyclerView),
+                StorageStrategy.createLongStorage()
+        ).withSelectionPredicate(
+                SelectionPredicates.createSelectAnything()
+        ).build()
+    }
+
     override fun onPause() {
         super.onPause()
         hideKeyboard()
@@ -141,6 +145,4 @@ class MainActivity : AppCompatActivity() {
     companion object {
         private val TAG = "VN/" + MainActivity::class.simpleName
     }
-
-
 }
\ No newline at end of file

app/src/main/res/drawable/selector.xml

 <?xml version="1.0" encoding="utf-8"?>
 <selector xmlns:android="http://schemas.android.com/apk/res/android">
     <item android:drawable="@android:color/holo_blue_light" android:state_activated="true" />
-    <item android:drawable="@android:color/white" />
+    <item android:drawable="@android:color/transparent" />
 </selector>
\ No newline at end of file