Anytime my MainActivity restarts because of changing of dark mode and i try to click i get nullpointer exception.
The error is below
I have a BaseFragment
lateinit var mContext:Context
lateinit var mActivity:Activity
var myId = ""
val firebaseMethods: FirebaseMethods by lazy { FirebaseMethods(requireActivity()) }
override fun onDestroy() {
super.onDestroy()
removeListeners()
}
override fun onAttach(context: Context) {
super.onAttach(context)
showLogI("onAttach")
}
override fun onDetach() {
super.onDetach()
showLogI("onDetach")
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
mContext = requireContext()
mActivity = requireActivity()
showLogI("onCreate")
if(getCurrentUser() != null){
myId = getCurrentUserId()
}
}
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?)
: View {
showLogI("onCreateView")
val view = setContentView(inflater, container, savedInstanceState)
return view
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
initView(view)
setListener()
initData()
}
protected abstract fun setContentView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?):View
protected abstract fun setListener()
protected abstract fun initData()
I also have a PostFragment
var posts:ArrayList<Post> = arrayListOf()
var pgPosts:ArrayList<Post> = arrayListOf()
var ids:ArrayList<String> = arrayListOf()
val keys:ArrayList<String> = arrayListOf()
var totalSize = 0
var query: Query? = null
var postAdapter:PostAdapter? = null
var counter = 0
var adUnit = ""
var adminId = ""
override fun onDestroy() {
super.onDestroy()
postAdapter?.removeListeners()
destroyAds()
}
private var _binding: FragmentPostBinding? = null
private val binding get() = _binding!!
override fun onDestroyView() {
super.onDestroyView()
_binding = null
}
override fun setContentView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View {
_binding = FragmentPostBinding.inflate(inflater, container, false)
return binding.root
}
override fun setListener() {
}
override fun initData() {
getArgs()
toggleOrientation()
showProgress()
setAdapter()
val spannableString = "No Internet Connection. Retry".createSpan("Retry"){ spannableString, start, end ->
mContext.setSpan(spannableString, "click", start, end, R.color.green){readPosts()}
}
if (mContext.isConnectingToInternet()) readPosts() else hideProgressWithSpan(spannableString)
adUnit = mContext.getString(R.string.ads_unit_video)
firebaseMethods.getAdmin { admin->
adminId = admin.admin_id
//adUnit = admin.native_ads_unit
}
}
fun changeLayout(orientation:String){
this.orientation = orientation
toggleOrientation()
setAdapter()
}
fun toggleOrientation(){
if (orientation == "big") {
max = 5
binding.recyclerview.lm()
} else if (orientation == "small") {
max = 15
binding.recyclerview.lm("grid", 3)
}
}
I get this null pointer exception
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.wh, PID: 26862
java.lang.NullPointerException at com.wh.ui.fragment.post.PostFragment.getBinding(PostFragment.kt:101)
at com.wh.ui.fragment.post.PostFragment.toggleOrientation(PostFragment.kt:160)
at com.wh.ui.fragment.post.PostFragment.changeLayout(PostFragment.kt:154)
2
Answers
Thanks a lot. I finally found the solution. I was checking if state is null for my bottom navigation view fragments and if null using new fragment, if not finding fragmentbytag. I just guessed to create the fragment without checking state and it worked.
As @Tenfour04 has said , you’re accessing the binding when the fragment has been detached. You need to first check if the fragment has been added like so