Can't use SharedPreferences in intended activity-CodePudding

There are two classes MainActivity and PickTimeForNotif in my project. In MainActivity getSharedPreferences works just fine, i can save my data and get it back. In PickTimeForNotif, however, the same method seems to do nothing.

Here's my simplified MainActivity class:

class MainActivity : AppCompatActivity(), ChangeCupDialogFragment.StringListener {
    @SuppressLint("SetTextI18n")
    
    //this is variable i'm saving
    private var drankToday = 0
    
    //function in which i save my value to SharedPreferences
    private fun saveWaterCountToInternalStorage(clickCounter: Int) {
        val sharedPref = this.getSharedPreferences("something", Context.MODE_PRIVATE)
        with (sharedPref.edit()){
            putInt(getString(R.string.clickCount), clickCounter)
            apply()
        }
    }
    
    //and here i get it from there
    private fun loadWaterCountToInternalStorage(): Int {
        val sharedPref = this.getSharedPreferences("something", Context.MODE_PRIVATE)
        return sharedPref.getInt(getString(R.string.clickCount), drankToday)
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.main_activity)
        val setupNotifButton = findViewById<Button>(R.id.setupNotifButton)

        setupNotifButton.setOnClickListener{
            val notifIntent = Intent(applicationContext, PickTimeForNotif::class.java)
            startActivity(notifIntent)
        }

    }
}

In setOnClickListener i intend my second activity PickTimeForNotif, here it is.

class PickTimeForNotif: AppCompatActivity(), TimePickerFragment.OnCompleteListener {
    val APP_PREFERENCES = "settings"
    private val SAVED_FROM_HOUR = "SetFromHour"
    private var FROM_HOUR = 99

    private fun saveTimeToInternalStorage(prefName1: String, Hour:Int) {
        val sharedPref = this.getSharedPreferences(APP_PREFERENCES, MODE_PRIVATE)
        with (sharedPref.edit()){
            putInt(prefName1, Hour)
            apply()
        }
    }

    private fun loadTimeFromInternalStorage() {
        val sharedPref = this.getSharedPreferences(APP_PREFERENCES, MODE_PRIVATE)
        if (sharedPref.contains(APP_PREFERENCES)) {
            sharedPref.getInt(SAVED_FROM_HOUR, FROM_HOUR)
        }
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.pick_time_activity)
        saveTimeToInternalStorage(SAVED_FROM_HOUR, 1)
        loadTimeFromInternalStorage()
        Toast.makeText(applicationContext,"$FROM_HOUR", Toast.LENGTH_SHORT).show()
    }
}

In the code above i'm trying to set value (1 for example ) to a SAVED_FROM_HOUR key and then get it back and assign to FROM_HOUR variable. However, the Toast shows 99, which means that new data wasn't loaded properly. I tried putting all code from loadTimeFromInternalStorage and saveTimeToInternalStorage to onCreate, but the result is same.

I also tried checking if the Preferences file exists after i call getSharedPreferences with

if (sharedPref.contains(APP_PREFERENCES))

but it does not.

So i'm asking to explain what am i doing wrong and why i can save the data in my MainActivity, but not in the second one. Thanks alot to anyone in advance!!

CodePudding user response：

In loadTimeFromInternalStorage(), you are fetching the value but not assigning to variable like this:

private fun loadTimeFromInternalStorage() {
        val sharedPref = this.getSharedPreferences(APP_PREFERENCES, MODE_PRIVATE)
        if (sharedPref.contains(APP_PREFERENCES)) {
            FROM_HOUR = sharedPref.getInt(SAVED_FROM_HOUR, FROM_HOUR)
        }
    }

Also, in this line FROM_HOUR = sharedPref.getInt(SAVED_FROM_HOUR, FROM_HOUR), the last parameter in getInt() method is the default value so you should make another constant for it or supply it 0.