嘿,我想在 kotlin 的串列中添加專案。我正在嘗試添加專案,但不幸的是,我遇到了錯誤,有人可以指導我如何做到這一點。
val prepareMutableLiveData: MutableLiveData<List<ConversationCount>> = MutableLiveData(
emptyList()
)
fun formatData() {
val conversationCount = mutableListOf<ConversationCount>()
viewModelScope.launch {
dateRange.forEachIndexed { index, dateRangeValue ->
val findData = data?.find {
dateRangeValue == it.dateObject
}
conversationCount.add(
ConversationCount(
setDay(dateRangeValue),
index,
findData != null
)
)
}
prepareMutableLiveData.value = mutableListOf(conversationCount) prepareMutableLiveData.value
}
}
我收到錯誤
Type mismatch.
Required:
ConversationCount
Found:
List<ConversationCount>?
Type mismatch.
Required:
List<ConversationCount>?
Found:
List<List<ConversationCount>?>
Type mismatch.
Required:
ConversationCount
Found:
MutableList<ConversationCount

我試過這個
prepareMutableLiveData.value = conversationCount prepareMutableLiveData.value
它給出了錯誤
Type mismatch.
Required:
ConversationCount
Found:
List<ConversationCount>
uj5u.com熱心網友回復:
因為conversationCount已經是一個串列,而您的實時資料也是一個串列,即MutableLiveData<List<ConversationCount>>您可以簡單地使用下面的代碼。
prepareMutableLiveData.value = conversationCount prepareMutableLiveData.value.orEmpty()
orEmpty()這是為了零安全。你也可以使用!!,但它不安全。
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