rxkotlin groupby不工作

你能帮我按照下面的json分组，并根据与RxKotlin的日期在kotlin中返回一个hashMap吗？ 对于kotlin来说非常简单，但对于Rxkotlin来说真的很困难。 谢谢

val groupedTransactions = accountTransactions.transactions？.groupBy {it.effectiveDate}

"transactions": [{ "id": "44e5b2bc484331ea24afd85ecfb212c8", "effectiveDate": "20/07/2017", "description": "Kaching TFR from JOHN CITIZEN
xmas donation", "amount": 12.00 }, { "id": "1506aeeb8c3a699b1e3c87db03156428", "effectiveDate": "20/07/2017", "description": "Wdl ATM CBA ATM CIRCULAR QUAY STATION NSW 221092 AUS", "amount": -200.00, "atmId": "129382" }, { "id": "9a899bfd978511e9605774e1d5222b67", "description": "Savings", "effectiveDate": "19/07/2017", "amount": 10.00 }, { "id": "1a6c48627cecaa2388b702fa33d751ff", "description": "PTAG COCA COLA AMATI", "effectiveDate": "12/07/2017", "amount": -2.20 }, { "id": "7ecc19e1a0be36ba2c6f05d06b5d3058", "description": "Wdl ATM CBA ATM TOWN HALL SQUARE NSW 253432 AUS", "effectiveDate": "04/07/2017", "amount": -50.00, "atmId": "137483" }, { "id": "b71bf065b640217dad602f86ac047722", "description": "BPAY - Telstra mobile", "effectiveDate": "04/07/2017", "amount": -49.00 },{ "id": "ef087651eb482bae4624478696f4ad4f", "description": "Transfer from REBECCA SHAW
Lorem ipsum", "effectiveDate": "03/07/2017", "amount": 150.00 }, { "id": "8cd283d8b7bacc277f2bae5e26ce6d1e", "description": "Savings", "effectiveDate": "01/07/2017", "amount": 200.00 }, { "id": "04117d2d74f5331f3ee4955da27cca7a", "effectiveDate": "28/06/2017", "description": "Transfer - Saturday drinks", "amount": -100.00 }, { "id": "821ae63dbe0c573eff8b69d451fb21bc", "effectiveDate": "21/06/2017", "description": "Wdl ATM CBA ATM CIRCULAR QUAY STATION NSW 221092 AUS", "amount": -200.00, "atmId": "129382" }] 

Answer 1

这看起来像rxkotlin问题。 我通过coroutine kotlin做了如下：

 doAsync { val groupedTransactions = accountTransactions.transactions ?.groupBy { it.effectiveDate } ....