比如说，联系人里面有个叫“jack"的人，只有名字，没有电话号码。

val queryFields2 = arrayOf(ContactsContract.CommonDataKinds.Phone.NUMBER)
                val phoneCursor = requireActivity().contentResolver
                    .query(
                        ContactsContract.CommonDataKinds.Phone.CONTENT_URI,
                        queryFields2,
                        ContactsContract.CommonDataKinds.Phone.CONTACT_ID + "=" + id,
                        null,
                        null
                    )
                phoneCursor?.use {
                    if (phoneCursor.count > 0) {
                        phoneCursor.moveToFirst()
                        Log.d("CrimeFragment", "测试")
                        crime.suspectPhoneNumber = phoneCursor.getString(0)
                    }
                    else{
                        crime.suspectPhoneNumber = ""
                    }

那么cursor的count会为0，因为找不到那个id的phone number。