how to access the properties of the host activity from a fragment dialog (kotlin)?

Issue

i have this fragment dialog and i want to edit some host activity properties when he click on btnOk in line 26 can any one help me or give me another way to communicate between a dialog fragment and its host activity `

package com.exemple.tic_tac_toe

import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.Button
import androidx.fragment.app.DialogFragment
import android.app.Activity




class restartDialog : DialogFragment() {
    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        val layout : View = inflater.inflate(R.layout.exit_layout , container , false)
        this.isCancelable = false
        val btnOk : Button = layout.findViewById(R.id.btnYes)
        val btnNo : Button = layout.findViewById(R.id.btnNO)
        btnOk.setOnClickListener(){
            dismiss()
            /////here acces the host activity properties and change them
        }
        btnNo.setOnClickListener(){
            dismiss()
        }
        return  layout
    }
}

`

Solution

I think the better approach would be to use an interface or a callback, rather than having the DialogFragment access the Activity properties.

You can create an interface:

interface DialogClickListener {
    fun dialogOkClicked()
    fun dialogCancelClicked()
}

Make the hosting Activity implement it:

class YourActivity: AppCompatActivity(), DialogClickListener {
    
    override fun dialogOkClicked() {
    
    }

    override fun dialogCancelClicked() {
    
    }
}

And in your DialogFragment, call those methods in case the Activity implements them:

btnOk.setOnClickListener(){
    (activity as? DialogClickListener)?.dialogOkClicked()
    dismiss()
    
}
btnNo.setOnClickListener(){
    (activity as? DialogClickListener)?.dialogCancelClicked()
    dismiss()
}

This would allow you to use this DialogFragment in other places and not inside a specific hosting Activity.

Answered By - gioravered