Question

我刚刚将项目中的所有可序列化类更改为parcelable类。一切都工作正常，除了那个由包含另一个ArrayList的ArrayList组成的类。我已经调试过了。编写此ArrayList时没有错误。但我在阅读时遇到错误。

这是发生错误的类：

public class Timetable implements Parcelable
{
private int actLap = 0;
private ArrayList<Lap> timetable;
private ArrayList<Location> loggedLocations;
private Date startTime; ...
...
public void writeToParcel(Parcel out, int flags)
{
    out.writeInt(actLap);
    out.writeTypedList(timetable); //no error here
    out.writeTypedList(loggedLocations); ...
...
    private Timetable(Parcel in)
{
    actLap          = in.readInt();
    in.readTypedList(timetable, Lap.CREATOR); //error after this line
    in.readTypedList(loggedLocations, Location.CREATOR);
    startTime       = (Date)in.readSerializable();
    bestLap         = in.readParcelable(Lap.class.getClassLoader());
    track           = in.readParcelable(Track.class.getClassLoader());
    description     = in.readString();
}

以下是其他课程：

public class Lap implements Parcelable
{   
private ArrayList<Time> sectorTimes = new ArrayList<Time>();
private Time laptime; ...
...
public void writeToParcel(Parcel out, int flags)
{
    out.writeTypedList(sectorTimes);
    out.writeParcelable(laptime,flags);
}

public static final Parcelable.Creator<Lap> CREATOR = new Parcelable.Creator<Lap>()
{
    public Lap createFromParcel(Parcel in)
    {
        return new Lap(in);
    }

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

private Lap(Parcel in)
{
    in.readTypedList(sectorTimes, Time.CREATOR);
    laptime     = in.readParcelable(Time.class.getClassLoader());
}

这节课：

public class Time implements Parcelable
{
private long timeLong;
private String timeString;...
...
public void writeToParcel(Parcel out, int flags)
{
    out.writeLong(timeLong);
    out.writeString(timeString);
}

public static final Parcelable.Creator<Time> CREATOR = new Parcelable.Creator<Time>()
{
    public Time createFromParcel(Parcel in)
    {
        return new Time(in);
    }

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

private Time(Parcel in)
{
    timeLong = in.readLong();
    timeString = in.readString();
}

就像我已经说过的，一切正常（有更多的Parcelable类，我通过意图（包括一个ArrayList）传递，并保存在文件中）。那么你们可以帮我写一下双ArrayList吗？提前致谢

Answer 1

如果您的代码是已发布的，那么您只是错过了ArrayLists的初始化，即

private Timetable(Parcel in)
{
    // readTypeList() needs an existing List<> to load.
    timetable = new ArrayList<Lap>();
    loggedLocations = new ArrayList<Location>();

    actLap          = in.readInt();
    in.readTypedList(timetable, Lap.CREATOR);
    in.readTypedList(loggedLocations, Location.CREATOR);
    ...

读取和写入包含Parcelable Objects的ArrayLists的ArrayList以传入Intent

1 个答案: