Fixed bug with fragments being added twice

app/build.gradle

@@ -10,8 +10,8 @@ android {
         applicationId "com.paktalin.vocabularynotebook"
         minSdkVersion 15
         targetSdkVersion 28
-        versionCode 2
-        versionName "1.1"
+        versionCode 3
+        versionName "1.2"
         multiDexEnabled true
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         vectorDrawables {

app/src/main/java/com/paktalin/vocabularynotebook/utils/ActivityUtil.kt

@@ -15,6 +15,9 @@ val progressFragment: Fragment = ProgressFragment()
 
 fun addFragment(fragmentManager: FragmentManager, fragment: Fragment, containerId: Int, arguments: Bundle?) {
     fragment.arguments = arguments
+    // remove progressFragment if it exists
+    if(fragmentManager.findFragmentById(fragment.id) != null)
+        removeFragment(fragmentManager, fragment)
     fragmentManager.beginTransaction().add(containerId, fragment).commitAllowingStateLoss()
 }