copyToRealmOrUpdate清除RealmList

Question

当我想更新一个对象而我无法找到解决方案时，我遇到了一些RealClists的麻烦。 我知道有一个类似的主题，但它没有答案。

以下是我的两个课程：

public class Category extends RealmObject {

@PrimaryKey
private long id;

private String label;

private boolean isIncome;

private double defaultBudget;

private boolean isArchived;

private RealmList<Amount> amounts;

private RealmList<AutomaticTransaction> automaticTransactions;

}

public class Amount extends RealmObject {

@PrimaryKey
private long id;

private Category category;

private int day;

private Month month;

private String label;

private double amount;
}

我通过创建具有旧属性的新类别来更新类别，然后设置新值

Category updatedCategory = category.getUpdatedCategory();
updatedCategory.setLabel(labelEditText.getText().toString());
updatedCategory.setDefaultBudget(budget);
databaseHandler.addOrUpdateCategory(updatedCategory);

public Category getUpdatedCategory(){
    return(new Category(id, label, isIncome, defaultBudget, amounts, 
    automaticTransactions));
}

在交易之前，列表已满，在它清空后，我不明白为什么。

 public void addOrUpdateCategory(final Category category){
    Log.e("test",category.getAmounts().size() + "");
    realm.executeTransaction(new Realm.Transaction() {
        @Override
        public void execute(Realm realm) {
            realm.copyToRealmOrUpdate(category);
            Log.d("DatabaseHandler","add or update : " + category);
        }
    });
    Log.e("test2",category.getAmounts().size() + "");
}

E/test: 31
D/DatabaseHandler: add or update : Category  id : 7 - label : Fast food 
& restaurants  - income : false - defaultBudget : 50.0 - archived : 
false - amounts : 0 - automaticTransactions : 0
E/test2: 0

感谢您的帮助，我真的被困住了。