DialogFragment默认左右下会有边距

这个需要重写一下onstart，关键属性，必须给设置背景图

class MyBottomDialogFragment : DialogFragment() {

    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
        val dialog = Dialog(requireContext())
        dialog.setContentView(R.layout.layout_koi_box)

        // 设置底部弹出的样式
//        dialog.window?.setLayout(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT)
//        dialog.window?.setGravity(Gravity.BOTTOM)

        // 初始化和设置 RecyclerView
        val recyclerView1 = dialog.findViewById<RecyclerView>(R.id.rv_koi_box)
        val recyclerView2 = dialog.findViewById<RecyclerView>(R.id.rv_box_chat_list)
        setupRecyclerView(recyclerView1)
        setupRecyclerView(recyclerView2)


        return dialog
    }

    @Override
    override fun onStart() {
        super.onStart()
        // 获取当前 Dialog 对象的 Window
        val window = dialog!!.window
        if (window != null) {
            // 清除窗口的内边距和偏移量
            window.decorView.setPadding(0, 0, 0, 0)
            window.setGravity(Gravity.BOTTOM)

            // 设置宽度为 MATCH_PARENT，高度自适应内容
            window.setLayout(
                WindowManager.LayoutParams.MATCH_PARENT,
                WindowManager.LayoutParams.WRAP_CONTENT
            )

//            // 设置背景透明
            window.setBackgroundDrawable(ColorDrawable(Color.TRANSPARENT))
        }
    }

}