Question

我有一个实现Parcelable interface的包装类。我使用这个包装器在活动之间传递ArrayList。它工作正常，但在另一个活动中检索int时，一个0字段始终提供ArrayList。请在下面找到我的代码。我究竟做错了什么？是否有任何尺寸限制？

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

public class ModelDeviceDetails implements Parcelable{
    String responseCode;
    String nickName;
    float latitude;
    float longitude;
    String deviceName;
    String uniqueId;
    String batLevel;
    int usedChaseModes;
    int plannedChaseModes;
    int usedLocateNow;
    int plannedLocateNow;

    public ModelDeviceDetails() {}

    public ModelDeviceDetails(Parcel source) {
        deviceName = source.readString();
        uniqueId = source.readString();
        nickName = source.readString();
        latitude = source.readFloat();
        longitude = source.readFloat();
        batLevel = source.readString();
        usedChaseModes = source.readInt();
        plannedChaseModes = source.readInt();
        usedLocateNow = source.readInt();
        plannedLocateNow = source.readInt();
        responseCode = source.readString();
    }

    @Override
    public int describeContents() {
        // TODO Auto-generated method stub
        return 0;
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeString(this.deviceName);
        dest.writeString(this.uniqueId);
        dest.writeString(this.nickName);
        dest.writeFloat(this.latitude);
        dest.writeFloat(this.longitude);    
        dest.writeString(this.batLevel);
        dest.writeInt(this.usedChaseModes);
        dest.writeInt(this.usedLocateNow);
        dest.writeInt(this.plannedChaseModes);
        dest.writeInt(this.plannedLocateNow);
        dest.writeString(this.responseCode);
    }

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

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

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

我在主要活动中传递了ArrayList，如下所示。

listViewActivity.putParcelableArrayListExtra("devices",devices);

检索我的listViewActivity，

中的列表

deviceList = intent.getParcelableArrayListExtra("devices");

我在发送列表之前检查了所有字段都正确填充。在listViewActivity其他字段也正确。但是只有一个字段总是提供0（我猜它会给int提供默认值）。请建议任何其他方法。

Answer 1

public ModelDeviceDetails(Parcel source) {
    deviceName = source.readString();
    uniqueId = source.readString();
    nickName = source.readString();
    latitude = source.readFloat();
    longitude = source.readFloat();
    batLevel = source.readString();
    usedChaseModes = source.readInt();
    plannedChaseModes = source.readInt(); // <-------- this
    usedLocateNow = source.readInt(); // <-------- and this
    plannedLocateNow = source.readInt();
    responseCode = source.readString();
}

@Override
public void writeToParcel(Parcel dest, int flags) {
    dest.writeString(this.deviceName);
    dest.writeString(this.uniqueId);
    dest.writeString(this.nickName);
    dest.writeFloat(this.latitude);
    dest.writeFloat(this.longitude);    
    dest.writeString(this.batLevel);
    dest.writeInt(this.usedChaseModes);
    dest.writeInt(this.usedLocateNow);
    dest.writeInt(this.plannedChaseModes);
    dest.writeInt(this.plannedLocateNow);
    dest.writeString(this.responseCode);
}

如果你在你的班级中实施Parcelable，那么你可以发送：

ArrayList<ModelDeviceDetails> list = new ArrayList<ModelDeviceDetails>();
list.add(new ModelDeviceDetails(...));
list.add(new ModelDeviceDetails(...));
Intent mySendingActivity = new Intent(getApplicationContext(), MySendingActivity.class);
mySendingActivity.putParcelableArrayListExtra("details", list);

并参与您的活动：

Bundle b = getIntent().getExtras();
ArrayList<ModelDeviceDetails> l = b.getParcelableArrayList("details");
Log.i("MySendingActivity", "Details:" + l);

Answer 2

我找不到解决此问题的方法，并使用Serializable代替Parcelable进行管理 包装类

import java.io.Serializable;

public class DeviceDetails implements Serializable {
    private static final long serialVersionUID = 1L;
    public DeviceDetails(){

    }
    String responseCode;    
    String nickName;
    float latitude;
    float longitude;
    String deviceName;
    String uniqueId;
    String batLevel;
    int usedChaseModes;
    int plannedChaseModes;
    int usedLocateNow;
    int plannedLocateNow;

    //getters and setters
}

发送信息

Intent intent = new Intent(getApplicationContext(), MySendingActivity.class);
Bundle mBundle = new Bundle();
mBundle.putSerializable("myKey", deviceDetails);
intent.putExtras(mBundle);              
startActivity(intent);

deviceDetails以上

的类型为ArrayList<DeviceDetails>。

接收信息

ArrayList<DeviceDetails> deviceList = (ArrayList<DeviceDetails>) intent.getSerializableExtra("myKey");

为Pracelable对象设置的一个字段值

2 个答案: