Java 将HashMap与自定义对象绑定

我对

onSaveInstanceState（）

中的Bundle

HashMap

有问题

logcat消息如下所示：

E/AndroidRuntime（12445）：android.os.BadParcelableException:ClassNotFoundException解组时：com.myapp.model.StationHashMap

已经尝试了一些解决方案：

在

onSaveInstanceState（）

中，添加

bundle.setClassLoader（getClass（）.getClassLoader（））

在

onSaveInstanceState（）

中，使用

bundle.putSerializable（保存实例键映射，mStationMap）

直接将HashMap放在bundle中，但是logcat消息会变成com.myapp.model.Station

以下代码：

• MapFragment.java：扩展

  SupportMapFragment

  ，我想在

  onSaveInstanceState（）中保存以前的状态数据

• StationHashMap.java：存储HashMap，实现

  Parcelable

• Station.java：存储所有站点数据，还实现了

  Parcelable

MapFragment.java

  private HashMap<String, Station> mStationMap;
  ...

    @Override
    public void onSaveInstanceState(Bundle outState) {
    StationHashMap stationHashMap = new StationHashMap();
    stationHashMap.setStationMap(mStationMap);

    outState.putParcelable(SAVE_INSTANCE_KEY_SATION_MAP, stationHashMap);
  }

public class StationHashMap implements Parcelable {
    private HashMap<String, Station> mStationMap = new HashMap<String, Station>();

    public StationHashMap() {
    }

    public void setStationMap(HashMap<String, Station> stationMap) {
        mStationMap = stationMap;
    }

    public HashMap<String, Station> getStationMap() {
        return mStationMap;
    }

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

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        Log.d(this.toString(), "in writeToParcel()");

        final int mapSize = mStationMap.size();

        dest.writeInt(mapSize);

        if (mapSize > 0) {
            for (Map.Entry<String, Station> entry : mStationMap.entrySet()) {
                dest.writeString(entry.getKey());

                Station station = entry.getValue();

                dest.writeInt(station.getId());
                dest.writeInt(station.getNo());
                dest.writeString(station.getName());
                dest.writeString(station.getAddress());
                dest.writeDouble(station.getLat());
                dest.writeDouble(station.getLng());
                dest.writeString(station.getDesc());
                dest.writeInt(station.getBikeNum());
                dest.writeInt(station.getEmptyNum());
            }
        }

    }

    public static final Creator<StationHashMap> CREATOR = new Creator<StationHashMap>() {

        @Override
        public StationHashMap createFromParcel(Parcel source) {
            return new StationHashMap(source);
        }

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

    };

    private StationHashMap(Parcel source) {
        Log.d(this.toString(), "in StationHashMap()");

        final int mapSize = source.readInt();

        for (int i = 0; i < mapSize; i++) {
            String key = source.readString();
            Station station = new Station();

            station.setId(source.readInt());
            station.setNo(source.readInt());
            station.setName(source.readString());
            station.setAddress(source.readString());
            station.setLat(source.readDouble());
            station.setLng(source.readDouble());
            station.setDesc(source.readString());
            station.setBikeNum(source.readInt());
            station.setEmptyNum(source.readInt());

            mStationMap.put(key, station);
        }
    }
}

public class Station implements Parcelable {
    private int mId;
    private int mNo;
    private String mName;

    public Station() {

    }

  // getters and setters...

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

    private void readFromParcel(Parcel in) {
        mId = in.readInt();
        mNo = in.readInt();
        mName = in.readString();
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeInt(mId);
        dest.writeInt(mNo);
    }

    private Station(Parcel in) {
        readFromParcel(in);
    }

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

        @Override
        public Station createFromParcel(Parcel source) {
            return new Station(source);
        }

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

}

私有HashMap mStationMap；
...
@凌驾
SaveInstanceState上的公共无效（束超出状态）{
StationHashMap StationHashMap=新的StationHashMap（）；
setStationMap（mStationMap）；
outState.putParcelable（保存实例、密钥、状态图、stationHashMap）；
}

StationHashMap.java中的方法是引用自：[问题]：

StationHashMap.java

  private HashMap<String, Station> mStationMap;
  ...

    @Override
    public void onSaveInstanceState(Bundle outState) {
    StationHashMap stationHashMap = new StationHashMap();
    stationHashMap.setStationMap(mStationMap);

    outState.putParcelable(SAVE_INSTANCE_KEY_SATION_MAP, stationHashMap);
  }

public class StationHashMap implements Parcelable {
    private HashMap<String, Station> mStationMap = new HashMap<String, Station>();

    public StationHashMap() {
    }

    public void setStationMap(HashMap<String, Station> stationMap) {
        mStationMap = stationMap;
    }

    public HashMap<String, Station> getStationMap() {
        return mStationMap;
    }

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

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        Log.d(this.toString(), "in writeToParcel()");

        final int mapSize = mStationMap.size();

        dest.writeInt(mapSize);

        if (mapSize > 0) {
            for (Map.Entry<String, Station> entry : mStationMap.entrySet()) {
                dest.writeString(entry.getKey());

                Station station = entry.getValue();

                dest.writeInt(station.getId());
                dest.writeInt(station.getNo());
                dest.writeString(station.getName());
                dest.writeString(station.getAddress());
                dest.writeDouble(station.getLat());
                dest.writeDouble(station.getLng());
                dest.writeString(station.getDesc());
                dest.writeInt(station.getBikeNum());
                dest.writeInt(station.getEmptyNum());
            }
        }

    }

    public static final Creator<StationHashMap> CREATOR = new Creator<StationHashMap>() {

        @Override
        public StationHashMap createFromParcel(Parcel source) {
            return new StationHashMap(source);
        }

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

    };

    private StationHashMap(Parcel source) {
        Log.d(this.toString(), "in StationHashMap()");

        final int mapSize = source.readInt();

        for (int i = 0; i < mapSize; i++) {
            String key = source.readString();
            Station station = new Station();

            station.setId(source.readInt());
            station.setNo(source.readInt());
            station.setName(source.readString());
            station.setAddress(source.readString());
            station.setLat(source.readDouble());
            station.setLng(source.readDouble());
            station.setDesc(source.readString());
            station.setBikeNum(source.readInt());
            station.setEmptyNum(source.readInt());

            mStationMap.put(key, station);
        }
    }
}

public class Station implements Parcelable {
    private int mId;
    private int mNo;
    private String mName;

    public Station() {

    }

  // getters and setters...

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

    private void readFromParcel(Parcel in) {
        mId = in.readInt();
        mNo = in.readInt();
        mName = in.readString();
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeInt(mId);
        dest.writeInt(mNo);
    }

    private Station(Parcel in) {
        readFromParcel(in);
    }

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

        @Override
        public Station createFromParcel(Parcel source) {
            return new Station(source);
        }

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

}

公共类StationHashMap实现可包裹{
私有HashMap mStationMap=新HashMap（）；
公共站点hashmap（）{
}
公共无效setStationMap（HashMap stationMap）{
mStationMap=stationMap；
}
公共HashMap getStationMap（）{
返回mStationMap；
}
@凌驾
公共int描述内容（）{
返回0；
}
@凌驾
公共无效写入包裹（包裹目的地，内部标志）{
Log.d（this.toString（），“in writeToParcel（）”；
final int-mapSize=mStationMap.size（）；
目的写入（mapSize）；
如果（贴图大小>0）{
对于（Map.Entry:mStationMap.entrySet（））{
dest.writeString（entry.getKey（））；
Station=entry.getValue（）；
dest.writeInt（station.getId（））；
dest.writeInt（station.getNo（））；
dest.writeString（station.getName（））；
dest.writeString（station.getAddress（））；
dest.writeDouble（station.getLat（））；
dest.writeDouble（station.getLng（））；
dest.writeString（station.getDesc（））；
dest.writeInt（station.getBikeNum（））；
dest.writeInt（station.getEmptyNum（））；
}
}
}
公共静态最终创建者=新创建者（）{
@凌驾
公共站点HashMap createFromParcel（地块源）{
返回新的StationHashMap（源）；
}
@凌驾
public StationHashMap[]新数组（整数大小）{
返回新的StationHashMap[大小]；
}
};
专用站点HashMap（地块源）{
Log.d（this.toString（），“在StationHashMap（）中”）；
final int mapSize=source.readInt（）；
对于（int i=0；i

Station.java

  private HashMap<String, Station> mStationMap;
  ...

    @Override
    public void onSaveInstanceState(Bundle outState) {
    StationHashMap stationHashMap = new StationHashMap();
    stationHashMap.setStationMap(mStationMap);

    outState.putParcelable(SAVE_INSTANCE_KEY_SATION_MAP, stationHashMap);
  }

public class StationHashMap implements Parcelable {
    private HashMap<String, Station> mStationMap = new HashMap<String, Station>();

    public StationHashMap() {
    }

    public void setStationMap(HashMap<String, Station> stationMap) {
        mStationMap = stationMap;
    }

    public HashMap<String, Station> getStationMap() {
        return mStationMap;
    }

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

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        Log.d(this.toString(), "in writeToParcel()");

        final int mapSize = mStationMap.size();

        dest.writeInt(mapSize);

        if (mapSize > 0) {
            for (Map.Entry<String, Station> entry : mStationMap.entrySet()) {
                dest.writeString(entry.getKey());

                Station station = entry.getValue();

                dest.writeInt(station.getId());
                dest.writeInt(station.getNo());
                dest.writeString(station.getName());
                dest.writeString(station.getAddress());
                dest.writeDouble(station.getLat());
                dest.writeDouble(station.getLng());
                dest.writeString(station.getDesc());
                dest.writeInt(station.getBikeNum());
                dest.writeInt(station.getEmptyNum());
            }
        }

    }

    public static final Creator<StationHashMap> CREATOR = new Creator<StationHashMap>() {

        @Override
        public StationHashMap createFromParcel(Parcel source) {
            return new StationHashMap(source);
        }

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

    };

    private StationHashMap(Parcel source) {
        Log.d(this.toString(), "in StationHashMap()");

        final int mapSize = source.readInt();

        for (int i = 0; i < mapSize; i++) {
            String key = source.readString();
            Station station = new Station();

            station.setId(source.readInt());
            station.setNo(source.readInt());
            station.setName(source.readString());
            station.setAddress(source.readString());
            station.setLat(source.readDouble());
            station.setLng(source.readDouble());
            station.setDesc(source.readString());
            station.setBikeNum(source.readInt());
            station.setEmptyNum(source.readInt());

            mStationMap.put(key, station);
        }
    }
}

public class Station implements Parcelable {
    private int mId;
    private int mNo;
    private String mName;

    public Station() {

    }

  // getters and setters...

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

    private void readFromParcel(Parcel in) {
        mId = in.readInt();
        mNo = in.readInt();
        mName = in.readString();
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeInt(mId);
        dest.writeInt(mNo);
    }

    private Station(Parcel in) {
        readFromParcel(in);
    }

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

        @Override
        public Station createFromParcel(Parcel source) {
            return new Station(source);
        }

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

}

公共类站实现可包裹{
私人int mId；
私人国际mNo；
私有字符串mName；
公共电台（）{
}
//接球手和接球手。。。
@凌驾
公共int描述内容（）{
返回0；
}
private void readFromParcel（地块位于中）{
mId=in.readInt（）；
mNo=in.readInt（）；
mName=in.readString（）；
}
@凌驾
公共无效写入包裹（包裹目的地，内部标志）{
目的地写入（mId）；
目的地记录（mNo）；
}
私人车站（包裹内）{
从包裹中读取；
}
public static final Parcelable.Creator=新建Parcelable.Creator（）{
@凌驾
公共站点createFromParcel（地块源）{
返回新站点（源）；
}
@凌驾
公共电台[]新阵列（整数大小）{
返回新站点[大小]；
}
};
}

我现在也有同样的问题。看起来我还没有尝试的唯一选项是使用片段的参数保存状态。但是那真的是一个糟糕的练习。我用上面的方法练习。