我正在编写一个运行非本地服务的 android 应用程序，以便从 Internet 获取数据。我有一个绑定到所述服务并检索 Order 对象列表以显示它们的活动。
将列表从服务传递到活动时，似乎出了点问题。虽然这对我来说似乎很简单。
问题
列表中的所有项目，但索引 1 处的项目都是空值。
调试显示服务函数具有正确的列表并返回正确的列表：
这是服务中返回列表的函数：
public List<Order> getOrders() throws RemoteException {
synchronized(service.orders) {
// service.orders returns a hashmap<Integer, Order>
// where the key is the ID of the order
// The function returns a simple list, so we parse to an ArrayList
List<Order> result = new ArrayList<Order>(service.orders.values());
return result;
}
}
这是 Activity 中调用服务并检索列表的函数（其中 api 是绑定到服务的结果）：
handler.post(new Runnable() {
public void run() {
try {
List<Order> result = api.getOrders();
displayOrders(result);
} catch (Throwable t) {
Log.e(TAG, "Error while updating the UI with orders", t);
}
}
});
这让我完全被难住了，因为我还有一个查看客户的活动和一个返回客户列表的服务功能，并且完美无缺。两者的主要区别在于 Customer 没有任何自定义对象属性，而 Order 有一些。
编辑：为 Order 类添加了 Parcelable 实现（通过删除大部分原始属性来简化）：
/*
* Parcelabe interface implementation
*/
public static final Creator<Order> CREATOR = new Creator<Order>() {
public Order createFromParcel(Parcel source) {
return new Order(source);
}
public Order[] newArray(int size) {
return new Order[size];
}
};
public Order(Parcel source) {
ID = source.readInt();
OrderID = source.readInt();
CustomerID = source.readInt();
TotalAmount = source.readDouble();
TotalProducts = source.readDouble();
OrderDate = source.readString();
InvoiceDate = source.readString();
DeliveryDate = source.readString();
// Custom objects
Customer = source.readParcelable(Customer.class.getClassLoader());
History = new ArrayList<OrderHistory>();
source.readTypedList(History, OrderHistory.CREATOR);
State = source.readParcelable(OrderState.class.getClassLoader());
}
public int describeContents() {
return Order.class.hashCode();
}
public void writeToParcel(Parcel dest, int flags) {
dest.writeInt(ID);
dest.writeInt(OrderID);
dest.writeInt(CustomerID);
dest.writeDouble(TotalAmount);
dest.writeDouble(TotalProducts);
dest.writeString(OrderDate);
dest.writeString(InvoiceDate);
dest.writeString(DeliveryDate);
// Custom object
dest.writeParcelable(Customer, flags);
dest.writeParcelable(State, flags);
dest.writeTypedList(History);
}
编辑：为 OrderList 类添加了代码：
公共类 OrderList 扩展 ArrayList 实现 Parcelable {
/**
*
*/
private static final long serialVersionUID = 417326483896340670L;
public OrderList() {
}
public OrderList(Parcel in) {
readFromParcel(in);
}
/*
* Parcelabe interface implementation
*/
public OrderList(Collection<Order> values) {
this.addAll(values);
}
@SuppressWarnings("unchecked")
public static final Parcelable.Creator<OrderList> CREATOR = new Parcelable.Creator<OrderList>() {
public OrderList createFromParcel(Parcel in) {
return new OrderList(in);
}
public OrderList[] newArray(int arg0) {
return null;
}
};
private void readFromParcel(Parcel in) {
this.clear();
//First we have to read the list size
int size = in.readInt();
//Reading remember that we wrote first the Name and later the Phone Number.
//Order is fundamental
for (int i = 0; i < size; i++) {
Order o = new Order();
o = in.readParcelable(Order.class.getClassLoader());
this.add(o);
}
}
public int describeContents() {
return 0;
}
public void writeToParcel(Parcel dest, int flags) {
int size = this.size();
// We have to write the list size, we need him recreating the list
dest.writeInt(size);
// We decided arbitrarily to write first the Name and later the Phone Number.
for (int i = 0; i < size; i++) {
Order o = this.get(i);
dest.writeParcelable(o, flags);
}
}
}
任何指针？
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