Kotlin - Type mismatch: required: Context found: Context?

Question

I tried to make a PopupMenu

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)

    menu_btn.setOnClickListener {
        var menu: PopupMenu?
        menu = PopupMenu(this.context, it)
        menu.inflate(R.menu.card_menu)

        menu.setOnMenuItemClickListener {
            when(it.itemId) {
                R.id.menu_modify -> { Toast.makeText(context, "Modify", Toast.LENGTH_LONG).show()
                    true }

                R.id.menu_delete -> { Toast.makeText(context, "Delete", Toast.LENGTH_LONG).show()
                    true }

                else -> false
            }
        }

        menu.show()
    }
}

but I get wiggly red line under

menu = PopupMenu(this.context, it)

That says: Type mismatch. Required: Context Found: Contex?

and even when I use !! - I get this error

java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ImageView.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
    at com.example.emek1.myapplication.FragmentOne.onCreate(FragmentOne.kt:24)
    at android.support.v4.app.Fragment.performCreate(Fragment.java:2414)
    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1418)
    at android.support.v4.app.FragmentTransition.addToFirstInLastOut(FragmentTransition.java:1195)
    at android.support.v4.app.FragmentTransition.calculateFragments(FragmentTransition.java:1078)
    at android.support.v4.app.FragmentTransition.startTransitions(FragmentTransition.java:117)
    at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2408)
    at android.support.v4.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2366)
    at android.support.v4.app.FragmentManagerImpl.execSingleAction(FragmentManager.java:2243)
    at android.support.v4.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:654)
    at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:146)
    at android.support.v4.view.ViewPager.populate(ViewPager.java:1244)
    at android.support.v4.view.ViewPager.populate(ViewPager.java:1092)
    at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1622)

Note: that it's not in MainActivity.kt It's a Fragment.

Answer 1

Write this code

context?.let {
    menu = PopupMenu(it, view)
}

Here view will be your anchor view of the popup.

instead of

menu = PopupMenu(this.context, it)

Answer 2

If it was a fragment you should call context like this.

menu = PopupMenu(activity!!, it)

or if you have the latest library you can do something like this

menu = PopupMenu(requireActivity(), it)