Kotlin: How to save values from RatingBar?

Question

I created a RatingBar in my application. It is for rating movies. I want value to be saved. When I login and go to that activity, I want to see that stars that I rated. It is difficult for me to find the answer because it is written in Kotlin and I'm new to it.

I searched for many other questions and answers, but with no result. Can you tell me what I need to change in my code?

class MovieDetailsActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_movie_details)

        fiveStars()

        val sharedPreference = getPreferences(Context.MODE_PRIVATE)
        val rating = sharedPreference.getFloat("numStars", 0f)
        ratingBar.rating = rating
    }

    private fun fiveStars() {
        val ratingBar = findViewById<RatingBar>(R.id.ratingBar)

         ratingBar.onRatingBarChangeListener = RatingBar.OnRatingBarChangeListener()
         { ratingBar: RatingBar, fl: Float, b: Boolean ->
             val sharedPreference = getSharedPreferences("numStars", Context.MODE_PRIVATE)
             val editor = sharedPreference.edit()

             editor.putFloat("numStars", fl)
             editor.apply()

             Log.d("rate", ratingBar.rating.toString())

         }
    }
}

I tried a lot of things, but nothing is working. Hope you could help me. Thanks!

Answer 1

It seems like you're using two different preferences.

Here you are calling getPreferences(Context.MODE_PRIVATE):

val sharedPreference = getPreferences(Context.MODE_PRIVATE)
val rating = sharedPreference.getFloat("numStars", 0f)
ratingBar.rating = rating

and here you are using a specific sharedPreferences:

val sharedPreference = getSharedPreferences("numStars", Context.MODE_PRIVATE)
val editor = sharedPreference.edit()

Either use getPreferences(Context.MODE_PRIVATE) in both cases, or use getSharedPreferences("numStars", Context.MODE_PRIVATE) in both cases