我正在尝试编写一个从activity到片段的数据传输，但我正在捕捉“NullPointerException”代码MainActivity：

val btn1 = findViewById<Button>(R.id.button)
        btn1.setOnClickListener {
            BlankFragment2.getNewInstance(321)
            val fm = supportFragmentManager
            val ft = fm.beginTransaction()
            ft.replace(R.id.fragment, BlankFragment2())
            ft.commit()
        }

代码片段：

class BlankFragment2 : Fragment() {
    var str: Int = 0
    companion object {
        fun getNewInstance(args: Int): BlankFragment2 {
            val fragment = BlankFragment2()
            fragment.arguments?.putInt("one", args)
            return fragment
        }
    }
    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
        // Inflate the layout for this fragment
        str = arguments!!.getInt("one")
        
        return inflater.inflate(R.layout.fragment_blank2, container, false)
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        val txt = view.findViewById<TextView>(R.id.textTest)
        txt.text = str.toString()
    }
}

我知道对空值的保护，但问题是，我确信传递了值，而null不在那里