How do I pass data from a popup activity to the parent activity without closing it?

private fun openPop(){
    val intent = Intent(this, Pop::class.java)
    startActivityForResult(intent,
        PICK_VALUE_ANOTHER);
}

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    super.onActivityResult(requestCode, resultCode, data)
    // Check which request we're responding to
    if (requestCode == PICK_VALUE_ANOTHER) {
        // Make sure the request was successful
        if (resultCode == Activity.RESULT_OK) {
            //Toast.makeText(this, "Data is ${data!!.data}", Toast.LENGTH_LONG).show()
            title = data!!.getStringExtra("name")
        }
    }
}

I have the code abode to open the Pop up activity. I can use the result, but I don't want it to close because I want to use the data to increment the font size.

Here is the code in the Pop up activity

button3.setOnClickListener(View.OnClickListener {
        val intent = intent
        intent.putExtra("name", "Mr. Bean")
        intent.putExtra("age", 85)
        setResult(RESULT_OK, intent)
        //finish()
    })

So, I have a view button with id button3 and I do get the information, but I want to keep the pop up open to send more information till the user click or tap out of the pop up window.

How do I do that?

Thanks

I want to do something or the same as the Amazon Kindle does as shown in the image