Koltin: Pass Context from inner class

Question

I want to make a toast in the foo method.
I have already tried different accesses (see comments). What am I doing wrong?
This didn't work:
class SettingsActivity : AppCompatActivity() {
    companion object{
        fun foo(context : Context){
            Toast.makeText(context, "Bar", Toast.LENGTH_LONG).show()
        }
    }
    private fun createListener() {

var listener = SharedPreferences.OnSharedPreferenceChangeListener { sharedPreferences, key ->   
                foo(this)
                //foo(this.applicationContext)
                //foo(this@SettingsActivity)
            }
    }
}

Working Example:
I could only call Foo if I passed a string instead of context and replaced the toast with a logging object. I called foo in the example with "foo("ttt")":
    //this works:
    fun foo(context : String){
        Log.v("TTTTTT", "QQQQQQQQQQQQ")
    }

There were no errors in the logcat.
Solved: Add lateinit var hi : SettingsActivity in the companion object and fill it before calling foo. Then you can omit the context parameter.

Kuldeep Saini · Answer

Your code seems correct, but just make sure you register the listener to your shared preference
getSharedPreferences("MyPre",Context.MODE_PRIVATE).registerOnSharedPreferenceChangeListen(listener)
Also you can modified your code from
class SettingsActivity : AppCompatActivity() {
companion object{
    fun foo(context : Context){
        Toast.makeText(context, "Bar", Toast.LENGTH_LONG).show()
    }
}
private fun createListener() {

var listener = SharedPreferences.OnSharedPreferenceChangeListener { sharedPreferences, key ->   
            foo(this)
            //foo(this.applicationContext)
            //foo(this@SettingsActivity)
        }
}

}
to
class SettingsActivity : AppCompatActivity() {
companion object{
    fun foo(context : Context){
        Toast.makeText(context, "Bar", Toast.LENGTH_LONG).show()
    }
}
private fun createListener() {

var listener = SharedPreferences.OnSharedPreferenceChangeListener { sharedPreferences, key ->  
           run{
           foo(this)
           }
            }  }}

Shalu T D · Answer

Please try below:
class SettingsActivity : AppCompatActivity() {
    companion object{
        fun foo(context : Context){
            Handler().post {
               Toast.makeText(context, "Bar", Toast.LENGTH_LONG).show()
            }
        }
    }
    private fun createListener() {

var listener = SharedPreferences.OnSharedPreferenceChangeListener { sharedPreferences, key ->   
                foo(this@SettingsActivity)
            }
    }
}

Mr. Patel · Answer

You'll need to pass context to your companion object for that, inside your activity on create just pass your context to companion object:
class SettingsActivity : AppCompatActivity() {
    companion object{
   var context:Context?=null
        fun foo(context){
            Toast.makeText(context, "Bar", Toast.LENGTH_LONG).show()
        }
    }
override fun onCreate(savedInstanceState: Bundle?) {
  context = this
}
    private fun createListener() {

var listener = SharedPreferences.OnSharedPreferenceChangeListener { sharedPreferences, key ->   
                foo(this)
                //foo(this.applicationContext)
                //foo(this@SettingsActivity)
            }
    }

Koltin: Pass Context from inner class

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