getParcelableArrayList返回一个Parcelable但我需要它来返回我的对象​​。 （java android）

Question

我收到如下错误：

Error:(133, 15) error: method setMonkeyBuisness in class QuoteBank cannot be applied to given types;
required: ArrayList<QuoteQuestion>
found: ArrayList<Parcelable>
reason: actual argument ArrayList<Parcelable> cannot be converted to     
ArrayList<QuoteQuestion> by method invocation conversion

QuoteQuestion和QuoteBank都实施了Parcelable及其所有方法。我也不能输入cast parcelable。

我是否正确使用Parcelable数组列表？

以下是QuoteBank的代码的一部分：

public class QuoteBank implements Parcelable{
    public static final String ARRAY_LIST_KEY = "arrayListKey";
    private ArrayList<QuoteQuestion> monkeyBuisness;


    public QuoteBank(){
    }
    @Override
    public void writeToParcel(Parcel dest, int flags) {
        Bundle bundle = new Bundle();

        bundle.putParcelableArrayList(ARRAY_LIST_KEY, monkeyBuisness);

        dest.writeBundle(bundle);
    }

    public static final Parcelable.Creator<QuoteBank> CREATOR = new Creator<QuoteBank>() {

        @Override
        public QuoteBank createFromParcel(Parcel source) {

            Bundle bundle = source.readBundle();
            QuoteBank qb = new QuoteBank();
            qb.setMonkeyBuisness(bundle.getParcelableArrayList(ARRAY_LIST_KEY));

            return qb;
        }

    public void setMonkeyBuisness(ArrayList<QuoteQuestion> monkeyBuisness) {
        this.monkeyBuisness = monkeyBuisness;
    }

以下是QuoteQuestion代码：

public class QuoteQuestion implements Parcelable{
public static final String QUOTE_TYPE = "quoteType";
public static final String QUOTE_NUMBER = "quoteNumber";
public static final String QUOTE_ARRAY = "quoteArray";
public static final String SPEAKER_ARRAY = "speakerArray";
public static final String ANSWER_INDEX_ARRAY = "answerIndexArray";
public static final String ANSWER_CHOICE_ARRAY = "answerChoiceArray";
public static final String CONTEXT_KEY = "contextKey";
public static final String CHOSEN_ANSWER = "chosenAnswer";
public static final String WORD_SPLIT = "wordSplit";
private int quoteNumber;
private String quoteType;
private ArrayList<String> quote;
private ArrayList<String> speaker;
private ArrayList<Integer> answerIndex;
private ArrayList<String> answerChoice;
private String context;
private String chosenAnswer;

@Override
public int describeContents() {
    return 0;
}

@Override
public void writeToParcel(Parcel dest, int flags) {
    Bundle bundle = new Bundle();

    // insert the key value pairs to the bundle

    bundle.putInt(QUOTE_NUMBER, quoteNumber);
    bundle.putString(QUOTE_TYPE, quoteType);
    bundle.putStringArrayList(QUOTE_ARRAY, quote);
    bundle.putStringArrayList(SPEAKER_ARRAY, speaker);
    bundle.putIntegerArrayList(ANSWER_INDEX_ARRAY, answerIndex);
    bundle.putStringArrayList(ANSWER_CHOICE_ARRAY, answerChoice);
    bundle.putString(CONTEXT_KEY, context);
    bundle.putString(CHOSEN_ANSWER, chosenAnswer);
    bundle.putStringArrayList(WORD_SPLIT, wordSplitTypeA);

    // write the key value pairs to the parcel
    dest.writeBundle(bundle);

}

public static final Parcelable.Creator<QuoteQuestion> CREATOR = new Creator<QuoteQuestion>() {

    @Override
    public QuoteQuestion createFromParcel(Parcel source) {
        // read the bundle containing key value pairs from the parcel
        Bundle bundle = source.readBundle();
        QuoteQuestion quoteQuestion = new QuoteQuestion();

        quoteQuestion.setQuoteNumber(bundle.getInt(QUOTE_NUMBER));
        quoteQuestion.setQuoteType(bundle.getString(QUOTE_TYPE));
        quoteQuestion.setQuote(bundle.getStringArrayList(QUOTE_ARRAY));
        quoteQuestion.setSpeaker(bundle.getStringArrayList(SPEAKER_ARRAY));
        quoteQuestion.setAnswerIndex(bundle.getIntegerArrayList(ANSWER_INDEX_ARRAY));
        quoteQuestion.setAnswerChoice(bundle.getStringArrayList(ANSWER_CHOICE_ARRAY));
        quoteQuestion.setContext(bundle.getString(CONTEXT_KEY));
        quoteQuestion.setChosenAnswer(bundle.getString(CHOSEN_ANSWER));
        quoteQuestion.setWordSplitTypeA(bundle.getStringArrayList(WORD_SPLIT));

        return quoteQuestion;
    }

    @Override
    public QuoteQuestion[] newArray(int size) {
        return new QuoteQuestion[size];
    }

};

此外我还有第二个问题 - 似乎所有大型多UI应用程序几乎所有类都可以实现parcelable？因为这是获取应用程序数据的唯一方法吗？这是最佳做法吗？

Answer 1

将您的陈述分成两部分，使用变量来保存正确输入的ArrayList，如下所示：

ArrayList<QuoteQuestion> qq = bundle.getParcelableArrayList(ARRAY_LIST_KEY);
qb.setMonkeyBuisness(qq);

为什么这样有效，而铸造却没有？我不知道。如果有人知道，请替换此段！

关于第二个问题，关于在所有地方实施Parcelable：所有活动的临时设计性质和意图的大量使用可能导致在许多地方需要Parcelable。某些应用程序设计模式可以帮助缓解问题。例如，遵循MVC技术，您的应用程序数据可以存在于模型中，可以通过从Application派生的自定义类访问。这允许大多数活动避免保存＆amp;恢复捆绑数据，因为它们只是模型的视图，它在设备轮换中持续存在等等。当然，这是一个更大的主题，有许多不同的方法，但希望这会引发一些想法。

Answer 2

写下来应该足够了：

qb.setMonkeyBuisness(bundle.<QuoteQuestion>getParcelableArrayList(ARRAY_LIST_KEY));