如何正确关闭DialogFragment？解决dismiss背景空白、onBackPressed退App问题

问题表现 #

尝试两种方案关闭DialogFragment均失败：

• 第一种方案调用dismiss()关闭，弹窗消失后底层页面完全空白，代码如下：

binding.closeBtn.setOnClickListener {
    dismiss()
}

• 第二种方案调用Activity返回方法关闭，触发后整个应用直接退出，代码如下：

close_btn.setOnClickListener {
    requireActivity().onBackPressed()
}

原有完整实现代码 #

class CongratulationsDialog : DialogFragment() {
    lateinit var bid :String
    lateinit var sharedPreference: SharedPreference
    var mLogoProgressDialog: ProgressDialog? = null
    var text : String = ""
    var uid :String = ""
    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?): View? {
        val binding = DataBindingUtil.inflate<CongratulationsDialogBinding>(
            inflater,
            R.layout.congratulations_dialog,
            container,
            false)
        dialog?.requestWindowFeature(Window.FEATURE_NO_TITLE)
        dialog?.setContentView(R.layout.congratulations_dialog)
        dialog?.window?.setLayout(WindowManager.LayoutParams.MATCH_PARENT, WindowManager.LayoutParams.WRAP_CONTENT)

        sharedPreference = activity?.let { SharedPreference(it) }!!
        bid = sharedPreference.getValueString("sendBid").toString()
        text = sharedPreference.getValueString("token").toString()
        uid = sharedPreference.getValueString("login_uid").toString()
        Log.d("checkLoginId",""+uid+"Bid"+bid)
        initializeLogoProgressDialog()
        loadBettingStatus(bid,text,binding)

        binding.closeBtn.setOnClickListener {
            dismiss()
        }
        binding.createNewBoastButton.setOnClickListener {
            view?.let { it1 ->
                Navigation.findNavController(it1)
                    .navigate(R.id.action_congratulationsDialog_to_newBoastFragment)
            }
        }
        return binding.root
    }

    private fun initializeLogoProgressDialog() {
        if (mLogoProgressDialog == null) {
            Log.w("PBFX", "initializeLogoProgressDialog called - mLogoProgressDialog = NULL")
        } else {
            Log.w("PBFX", "initializeLogoProgressDialog called - mLogoProgressDialog NOT NULL")
        }
        if (mLogoProgressDialog == null) {
            dismissLogoProgressDialog()
            mLogoProgressDialog = ProgressDialog(requireContext())
            mLogoProgressDialog!!.show()
            mLogoProgressDialog!!.setCancelable(false)
            mLogoProgressDialog!!.getWindow()!!
                .setBackgroundDrawable(ColorDrawable(Color.TRANSPARENT))
            mLogoProgressDialog!!.setContentView(R.layout.progress_bar)
        }
    }

    private fun loadBettingStatus(bid: String, text: String, binding: CongratulationsDialogBinding) {
        val apiInterface = RetrofitService.api.getInviteesDetails(bid,"Bearer "+text)

        apiInterface.enqueue( object : Callback<Invitees> {
            override fun onResponse(call: Call<Invitees>?, response: Response<Invitees>) {
                if (response.isSuccessful) {
                    dismissLogoProgressDialog()
                    if (response?.body() != null) {
                        if(response.body()!!.data.status.equals("completed")) {
                            binding.textView7.text =response.body()!!.data.name
                            if (uid.equals(response.body()!!.data.betWinner.uid)) {
                                binding.youTxt.setText("You")
                                if(response.body()!!.data.mode.equals("task")){
                                    binding.textView10.setText(response.body()!!.data.taskTitle)
                                }else{
                                    binding.textView10.setText("$"+response.body()!!.data.value)
                                }
                            } else {
                                dismissLogoProgressDialog()
                                binding.youTxt.setText(response.body()!!.data.betWinner.name)
                                if(response.body()!!.data.mode.equals("task")){
                                    binding.textView10.setText(response.body()!!.data.taskTitle)
                                }else{
                                    binding.textView10.setText("$"+response.body()!!.data.value)
                                }
                            }
                        }
                    }
                }else{
                    dismissLogoProgressDialog()
                }
            }
            override fun onFailure(call: Call<Invitees>?, t: Throwable?) {
                if (t != null) {
                    dismissLogoProgressDialog()
                    Log.d("gettingFailure",""+t.message)
                }
            }
        })
    }

    private fun dismissLogoProgressDialog() {
        if (mLogoProgressDialog != null) {
            mLogoProgressDialog!!.dismiss()
        }
        mLogoProgressDialog = null
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
       // close_btn.setOnClickListener {
       //     requireActivity().onBackPressed()
       // }
    }
    override fun getTheme() = R.style.RoundedCornersDialog
}

问题根因 #

1. 视图逻辑混用：onCreateView中已经通过DataBinding加载了布局并返回根视图，同时又手动调用dialog?.setContentView()重复设置布局，导致Dialog的视图层级混乱，dismiss时触发异常渲染。
2. 导航逻辑错误：你使用了Navigation组件管理页面跳转，DialogFragment作为导航栈中的目的地，直接调用dismiss()不会更新导航栈状态，导致返回后页面空白；直接调用Activity的onBackPressed()会直接回退整个Activity的栈，当前栈只有一个目的地时就会直接退出应用。

修复步骤 #

1. 删除onCreateView中重复配置Dialog的三行代码：

// 移除以下三行
dialog?.requestWindowFeature(Window.FEATURE_NO_TITLE)
dialog?.setContentView(R.layout.congratulations_dialog)
dialog?.window?.setLayout(WindowManager.LayoutParams.MATCH_PARENT, WindowManager.LayoutParams.WRAP_CONTENT)

2. 替换关闭按钮的点击逻辑，使用Navigation的回栈方法关闭弹窗：

binding.closeBtn.setOnClickListener {
    findNavController().popBackStack()
}

3. （可选）如果需要调整Dialog的宽高样式，重写onStart方法配置：

override fun onStart() {
    super.onStart()
    dialog?.window?.apply {
        setLayout(WindowManager.LayoutParams.MATCH_PARENT, WindowManager.LayoutParams.WRAP_CONTENT)
        setBackgroundDrawable(ColorDrawable(Color.TRANSPARENT))
    }
}

内容的提问来源于stack exchange，提问作者Jaanu