How Can We Achieve Shared View Model Communication Between A Fragment And Activity, Where The Activity Is Not The Parent

I am trying to achieve Fragment to Activity communication given that the Activity is not the parent Activity. So, I have a MainActivity that has a fragment called ContactListFragme

Solution 1:

Write an interface class with object/objects/Data types you need to sync

interfaceOnSaveClickListener{
    funonSaveClicked(contact: Contact)
}

Now in ContactListFragment class

classContactListFragment : Fragment(), OnSaveClickListener {

    overridefunonCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        (activity as AddContactACtivity).mOnSaveClickListener = this
    }

   
    overridefunonSaveClicked(contact: Contact) {
        // Whatever you want to do with the data
    }
        
}

In AddContactActivity,

classAddContactActivity {
   var mOnSaveClickListener : OnSaveClickListener? = nullprivatevoidwhenYouClickSave(contact: Contact){
       mOnSaveClickListener?.onSaveClicked(contact)
   }