问题描述
我只想知道如何读写ArrayList。我用Kotlin。
data class CustomerTxn(
@field:Serializedname("txn_note")
val txnNote: String? = null,@field:Serializedname("txn_date")
val txnDate: String? = null,@field:Serializedname("amount")
val amount: String? = null,@field:Serializedname("txn_type")
val txnType: String? = null,@field:Serializedname("contact")
val contact: String? = null,@field:Serializedname("transaction_images")
var transactionImages: ArrayList<String>? = null,@field:Serializedname("created_at")
val createdAt: String? = null,@field:Serializedname("cashbook")
val cashbook: String? = null,@field:Serializedname("view_type")
val viewType: String? = null,@field:Serializedname("id")
val id: String? = null,@field:Serializedname("modified_at")
val modifiedAt: String? = null
):Parcelable {
constructor(parcel: Parcel) : this(
parcel.readString(),parcel.readString(),parcel.readArrayList(null),parcel.readString()) {
}
override fun writetoParcel(parcel: Parcel,flags: Int) {
parcel.writeString(txnNote)
parcel.writeString(txnDate)
parcel.writeString(amount)
parcel.writeString(txnType)
parcel.writeString(contact)
parcel.writeList(transactionImages)
parcel.writeString(createdAt)
parcel.writeString(cashbook)
parcel.writeString(viewType)
parcel.writeString(id)
parcel.writeString(modifiedAt)
}
override fun describeContents(): Int {
return 0
}
companion object CREATOR : Parcelable.Creator<CustomerTxn> {
override fun createFromParcel(parcel: Parcel): CustomerTxn {
return CustomerTxn(parcel)
}
override fun newArray(size: Int): Array<CustomerTxn?> {
return arrayOfNulls(size)
}
}
这些行给我错误:
parcel.readArrayList(null)
parcel.writeList(transactionImages)
parcel.readArrayList(null)的错误:
类型不匹配。是否必选:ArrayList
parcel.writeList(transactionImages)的错误:
java类型不匹配(Mutable)List !但发现ArrayList
解决方法
我使用的是 Java 而不是 Kotlin ,但我认为可以通过相同的解决方案来解决此问题。
我经常使用:
- parcel.createStringArrayList()代替 parcel.readArrayList(null)
- parcel.writeStringList(transactionImages)代替 parcel.writeList(transactionImages)
很抱歉,但是您可以使用@Parcelize
创建一个Parcelable
类:
@Parcelize
data class CustomerTxn(
@field:SerializedName("txn_note")
val txnNote: String? = null,@field:SerializedName("txn_date")
val txnDate: String? = null,@field:SerializedName("amount")
val amount: String? = null,@field:SerializedName("txn_type")
val txnType: String? = null,@field:SerializedName("contact")
val contact: String? = null,@field:SerializedName("transaction_images")
var transactionImages: ArrayList<String>? = null,@field:SerializedName("created_at")
val createdAt: String? = null,@field:SerializedName("cashbook")
val cashbook: String? = null,@field:SerializedName("view_type")
val viewType: String? = null,@field:SerializedName("id")
val id: String? = null,@field:SerializedName("modified_at")
val modifiedAt: String? = null
): Parcelable
因此不必担心将ArrayList<String>
保存到包裹中。