我试图将自定义类实现为parcelable，并且我在从包裹中读取/写入这些类的列表时遇到问题。我有3个班，测验，问答。
在问题类下面给我一个错误：
in.readList(answers, Answer.class.getClassLoader());
这是我的班级， 测验：
public class Quiz implements Parcelable{
private List<Question> questions;
public Quiz(Parcel in) {
questions = new ArrayList<Question>();
in.readList(questions,Question.class.getClassLoader());
}
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel parcel, int i) {
parcel.writeList(questions);
}
public static final Parcelable.Creator<Quiz> CREATOR = new Parcelable.Creator<Quiz>() {
public Quiz createFromParcel(Parcel in) {
return new Quiz(in);
}
public Quiz[] newArray(int size) {
return new Quiz[size];
}
};
}
问题：
public class Question implements Parcelable {
private String question;
private List<Answer> answers;
public Question(Parcel in) {
answers = new ArrayList<Answer>();
in.readList(answers, Answer.class.getClassLoader());
}
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel parcel, int i) {
parcel.writeString(question);
parcel.writeList(answers);
}
public static final Parcelable.Creator<Question> CREATOR = new Parcelable.Creator<Question>() {
public Question createFromParcel(Parcel in) {
return new Question(in);
}
public Question[] newArray(int size) {
return new Question[size];
}
};
}
答案：
public class Answer implements Parcelable {
private String answer;
private boolean isCorrect = false;
public Answer(String answer) {
this.answer = answer;
}
public Answer(Parcel in) {
answer = in.readString();
isCorrect = in.readByte() != 0;
}
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel parcel, int i) {
parcel.writeString(answer);
parcel.writeByte((byte) (isCorrect ? 1 : 0));
}
public static final Parcelable.Creator<Answer> CREATOR = new Parcelable.Creator<Answer>() {
public Answer createFromParcel(Parcel in) {
return new Answer(in);
}
public Answer[] newArray(int size) {
return new Answer[size];
}
};
}
堆栈跟踪：
09-03 01:03:43.018 20659-20659/auf.ccs.appschool E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{auf.ccs.appschool/auf.ccs.appschool.QuizActivity}: java.lang.RuntimeException: Parcel android.os.Parcel@40516de0: Unmarshalling unknown type code 6815831 at offset 332
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1651)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
at android.app.ActivityThread.access$1500(ActivityThread.java:117)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:130)
at android.app.ActivityThread.main(ActivityThread.java:3691)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:507)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:847)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:605)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.RuntimeException: Parcel android.os.Parcel@40516de0: Unmarshalling unknown type code 6815831 at offset 332
at android.os.Parcel.readValue(Parcel.java:1913)
at android.os.Parcel.readListInternal(Parcel.java:2092)
at android.os.Parcel.readList(Parcel.java:1414)
at auf.ccs.appschool.Items.Question.<init>(Question.java:25)
at auf.ccs.appschool.Items.Question$1.createFromParcel(Question.java:67)
at auf.ccs.appschool.Items.Question$1.createFromParcel(Question.java:64)
at android.os.Parcel.readParcelable(Parcel.java:1981)
at android.os.Parcel.readValue(Parcel.java:1846)
at android.os.Parcel.readListInternal(Parcel.java:2092)
at android.os.Parcel.readList(Parcel.java:1414)
at auf.ccs.appschool.Items.Quiz.<init>(Quiz.java:28)
at auf.ccs.appschool.Items.Quiz$1.createFromParcel(Quiz.java:44)
at auf.ccs.appschool.Items.Quiz$1.createFromParcel(Quiz.java:41)
at android.os.Parcel.readParcelable(Parcel.java:1981)
at auf.ccs.appschool.Items.Video.<init>(Video.java:113)
at auf.ccs.appschool.Items.Video$1.createFromParcel(Video.java:132)
at auf.ccs.appschool.Items.Video$1.createFromParcel(Video.java:130)
at android.os.Parcel.readParcelable(Parcel.java:1981)
at android.os.Parcel.readValue(Parcel.java:1846)
at android.os.Parcel.readMapInternal(Parcel.java:2083)
at android.os.Bundle.unparcel(Bundle.java:208)
at android.os.Bundle.getParcelable(Bundle.java:1100)
at auf.ccs.appschool.QuizActivity.onCreate(QuizActivity.java:40)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
at android.app.ActivityThread.access$1500(ActivityThread.java:117)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:130)
at android.app.ActivityThread.main(ActivityThread.java:3691)
at java.lang.reflect.Method.invokeNative(Native Method)
答案 0 :(得分：2)
在您正在阅读的Question课程中
answers = new ArrayList<Answer>();
in.readList(answers, Answer.class.getClassLoader());
来自parcel，但正在写
parcel.writeString(question);
parcel.writeList(answers);
已修复Question构造函数：
public Question(Parcel in) {
question = in.readString();
answers = new ArrayList<Answer>();
in.readList(answers, Answer.class.getClassLoader());
}