android - ArrayList 不能转换为 Parcelable

Question

我收到以下错误:

• Key com..BookStatus 预期 Parcelable 但值是 ArrayList
• ClassCastException: ArrayList 无法转换为 Parcelable-> and therafter: 无法启动 Activity - NullPointerException

• ArrayList 确实有 BookStatus 对象 (listToPass) 的值

  • 键 com.example.books.BookStatus 应为 Parcelable，但值为 java.util.ArrayList。已返回默认值
  • 尝试强制转换生成的内部异常:
  • java.lang.ClassCastException: java.util.ArrayList 无法转换为 android.os.Parcelable
  • 在 com.example.books4locals.SearchActivity.onCreate(SearchActivity.java:46) -> 这是 bundle.getparcelable 方法

我能做什么？

HomeActivity.java

    ArrayList<BookStatus> listToPass = new ArrayList<BookStatus>(); // fill with smthg

        protected void onPostExecute(String result) {

            if (listToPass != null) {

                Intent i = new Intent(getApplicationContext(),
                        SearchActivity.class);
                //              ArrayList<BookStatus> bs = new ArrayList<BookStatus> (Arrays.asList(bArr));

                i.putParcelableArrayListExtra("com.example.books.BookStatus", listToPass);
                startActivity(i);

SearchActivity.java

          protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.searchactivity_main);

            Bundle bundle = getIntent().getExtras();
            ArrayList<BookStatus> bookStatus = bundle
                    .getParcelable("com.example.books.BookStatus");

BookStatus.java

         public class BookStatus implements Parcelable {

        public BookStatus() {
        }

        public BookStatus(Parcel in) {
            this.bookId=in.readInt();

            this.address=in.readString();
            this.name=in.readString();
            this.author=in.readString();
            this.lenderUserId=in.readInt();
            this.isbn=in.readInt();
            this.postcode=in.readString();
            this.town=in.readString();
            this.telnumber=in.readString();
            this.mail=in.readString();
            this.duration=in.readInt();
            }
                        @Override
            public int describeContents() {
                // TODO Auto-generated method stub
                return 0;
            }

            @Override
            public void writeToParcel(Parcel dest, int flags) {
                dest.writeInt(this.bookId);

                dest.writeString(this.address);
                dest.writeString(this.name);
                dest.writeString(this.author);
                dest.writeInt(this.lenderUserId);
                dest.writeInt(this.isbn);
                dest.writeString(this.postcode);
                dest.writeString(this.town);
                dest.writeString(this.telnumber);
                dest.writeString(this.mail);
                dest.writeInt(this.duration);

            }

             public void readFromParcel(Parcel parcel){
                    this.bookId = parcel.readInt();
                    this.address = parcel.readString();

                    this.name = parcel.readString();
                    this.author = parcel.readString();
                    this.lenderUserId = parcel.readInt();
                    this.isbn = parcel.readInt();
                    this.postcode = parcel.readString();
                    this.town = parcel.readString();
                    this.telnumber = parcel.readString();
                    this.mail = parcel.readString();
                    this.duration = parcel.readInt();
                  }




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

                 public BookStatus createFromParcel(Parcel in) {
             return new BookStatus(in);
         }

                 public BookStatus[] newArray(int size) {
             return new BookStatus[size];
         }
        };

Answer 1

尝试改变

 i.putParcelableArrayListExtra("com.example.books.BookStatus", listToPass);

到

i.putExtra("com.example.books.BookStatus", listToPass);

和

 bundle.getParcelable

到

 bundle.getParcelableArrayList