Question

我正在尝试实现Parcelable而不是Serializble，因为它应该更高效。从我的MainActivity我想将Message对象传递给另一个activity，我的类Message包含其他类。如果我通过这一个错误，我肯定我会遇到更多的错误，但是现在当我尝试运行我的应用程序时，我正在

这是我的消息类：

import java.util.ArrayList;

import android.os.Parcel;
import android.os.Parcelable;

public class Message implements Parcelable {

    int id;
    int space_id;
    String text;
    String html;
    String created_at;
    int[] comments;
    boolean is_liked;
    int[] liked_by;
    int[] starred_by;
    boolean is_starred;
    boolean is_followed;
    int[] followed_by;
    ArrayList<AttachmentsData> attachments;
    String url;
    int[] tags;
    boolean is_system;

    public User created_by;
    public Permissions persmissions;
    public Embed embed;
    public Tokens[] tokens;


    /** Parcelable **/
    public Message(Parcel in) {
        readFromParcel(in);
    }

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

    @Override
    public void writeToParcel(Parcel dest, int flags) { 
        dest.writeInt(id);
        dest.writeInt(space_id);
        dest.writeString(text);
        dest.writeString(html);
        dest.writeString(created_at);
        dest.writeIntArray(comments);
        dest.writeInt(is_liked ? 1 : 0);
        dest.writeIntArray(liked_by);
        dest.writeIntArray(starred_by);
        dest.writeInt(is_starred ? 1 : 0);
        dest.writeInt(is_followed ? 1 : 0);
        dest.writeIntArray(followed_by);
        dest.writeList(attachments);
        dest.writeString(url);
        dest.writeIntArray(tags);
        dest.writeInt(is_system ? 1 : 0);

        dest.writeParcelable(created_by, flags);
        dest.writeParcelable(persmissions, flags);
        dest.writeParcelable(embed, flags);
        dest.writeParcelableArray(tokens, flags);
    }

    private void readFromParcel(Parcel in) {
        id = in.readInt();
        space_id = in.readInt();
        text = in.readString();
        html = in.readString();
        created_at = in.readString();
        //in.readIntArray(comments);
        comments = in.createIntArray();
        is_liked = in.readInt() == 0;
        //in.readIntArray(liked_by);
        liked_by = in.createIntArray();
        //in.readIntArray(starred_by);
        starred_by = in.createIntArray();
        is_starred = in.readInt() == 0;
        is_followed = in.readInt() == 0;
        //in.readIntArray(followed_by);
        followed_by = in.createIntArray();
        in.readList(attachments, AttachmentsData.class.getClassLoader());
        url = in.readString();
        //in.readIntArray(tags);
        tags = in.createIntArray();
        is_system = in.readInt() == 0;

        created_by = in.readParcelable(User.class.getClassLoader());
        persmissions = in.readParcelable(Permissions.class.getClassLoader());
        embed = in.readParcelable(Embed.class.getClassLoader());
        tokens = in.readParcelable(Tokens.class.getClassLoader();
    }   

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

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

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



    /** Getters and setters, I'll spare you these **/

 }

这是我得到的错误：

FATAL EXCEPTION：main java.lang.RuntimeException：无法启动活动 ComponentInfo {com.example.incentive / com.example.incentive.Comments}： java.lang.ClassCastException：无法转换android.os.Parcelable [] to com.example.incentive.messagemodel.Tokens [] at android.app.ActivityThread.performLaunchActivity（ActivityThread.java:1967）在 android.app.ActivityThread.handleLaunchActivity（ActivityThread.java:1992）在android.app.ActivityThread.access $ 600（ActivityThread.java:127）at android.app.ActivityThread $ H.handleMessage（ActivityThread.java:1158）在android.os.Handler.dispatchMessage（Handler.java:99）at android.os.Looper.loop（Looper.java:137）at android.app.ActivityThread.main（ActivityThread.java:4441）at java.lang.reflect.Method.invokeNative（Native Method）at java.lang.reflect.Method.invoke（Method.java:511）at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:784）在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:551）at dalvik.system.NativeStart.main（Native方法）引起： java.lang.ClassCastException：无法转换android.os.Parcelable [] to com.example.incentive.messagemodel.Tokens [] at com.example.incentive.messagemodel.Message.readFromParcel（Message.java:94）在com.example.incentive.messagemodel.Message。（Message.java:35）在 com.example.incentive.messagemodel.Message $ 1.createFromParcel（Message.java:100）在 com.example.incentive.messagemodel.Message $ 1.createFromParcel（Message.java:1）在android.os.Parcel.readParcelable（Parcel.java:1992）at android.os.Parcel.readValue（Parcel.java:1854）at android.os.Parcel.readMapInternal（Parcel.java:2094）at android.os.Bundle.unparcel（Bundle.java:223）at android.os.Bundle.getParcelable（Bundle.java:1158）at com.example.incentive.Comments.onCreate（Comments.java:67）at android.app.Activity.performCreate（Activity.java:4465）at android.app.Instrumentation.callActivityOnCreate（Instrumentation.java:1049）在 android.app.ActivityThread.performLaunchActivity（ActivityThread.java:1931） ......还有11个

我现在认为相关的是：

引起：java.lang.ClassCastException：android.os.Parcelable [] 无法转换为com.example.incentive.messagemodel.Tokens [] at com.example.incentive.messagemodel.Message.readFromParcel（Message.java:94）

所以我可能做错了一件事： tokens = in.readParcelable（Tokens.class.getClassLoader（）;

这是我的Tokens-class：

import android.os.Parcel;
import android.os.Parcelable;

public class Tokens implements Parcelable {

    String type;
    String value;
    int start;
    int end;


    /** Parcelable related **/
    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeString(type);
        dest.writeString(value);
        dest.writeInt(start);
        dest.writeInt(end);
    }

    private Tokens(Parcel in) {
        type = in.readString();
        value = in.readString();
        start = in.readInt();
        end = in.readInt();
    }

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

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

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


    /** Getters and setters **/ 
}

我整个下午都在搜索，我看不清楚如何正确地做到这一点。有谁知道吗？

Answer 1

使用writeTypedArray和readTypedArray读取并将数组写入parcel

读

tokens = in.createTypedArray(Tokens.CREATOR);

写

in.writeTypedArray(tokens, flags);

Answer 2

试试这个......

替换

 tokens = in.readParcelable(Tokens.class.getClassLoader();

与

 tokens = in.readParcelableArray(Tokens.class.getClassLoader());

您正在编写Parcelable Array，但将其读作Parcelable

尝试在自定义对象数组上执行readParcelable时出现ClassCastException

2 个答案: