Android Intent 使用 Parcel 反序列化出错.
Android Parcel 可以序列化反序列化数据 .但上层的(Intent)却反序列化失败.
结论:
查看Android源代码, Intent 的Parcel 接口代码,也未能找出问题所在.
如下是我的测试代码 :
非持久化测试代码:
final Intent intent = new Intent("cn.eben.bookshelf.VIEW");
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
//
序列化前 Intent 内存
Intent { act=cn.eben.bookshelf.VIEW flg=0x10000000 }
Parcel parcel = Parcel.obtain();
intent.writeToParcel(parcel, 0);
byte[] data = parcel.marshall();
Parcel readParcel = Parcel.obtain();
readParcel.unmarshall(data, 0, data.length);
Intent readIntent = Intent.CREATOR.createFromParcel(readParcel);
// readIntent 内存状态, Intent 反序列化失败.
Intent { (has extras) }
null
null
null
null
null
Bundle[mParcelledData.dataSize=0]
0
null
null
null
null
context.startActivity(readIntent);// Activite 无法启动, Intent 无效
// 持久化测试代码 与内存状态
final Intent intent = new Intent("cn.eben.bookshelf.VIEW");
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
查看内存:
序列化前 Intent 内存
Intent { act=cn.eben.bookshelf.VIEW flg=0x10000000 }
Parcel parcel = Parcel.obtain();
intent.writeToParcel(parcel, 0);
byte[] data = parcel.marshall();
// 查看Data内存如下:
[22, 0, 0, 0, 99, 0, 110, 0, 46, 0, 101, 0, 98, 0, 101, 0, 110, 0, 46, 0, 98, 0, 111, 0, 111, 0, 107, 0, 115, 0, 104, 0, 101, 0, 108, 0, 102, 0, 46, 0, 86, 0, 73, 0, 69, 0, 87, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -1, -1, 0, 0, 0, 16, -1, -1, -1, -1, -1, -1, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -1, -1]
cv.put("intent", data); //将parcel对持久化.
///读取
byte[] data = cursor.getBlob(cursor.getColumnIndex("intent"));
//查看读取到的 Data内存如下: 与写入的相同.
[22, 0, 0, 0, 99, 0, 110, 0, 46, 0, 101, 0, 98, 0, 101, 0, 110, 0, 46, 0, 98, 0, 111, 0, 111, 0, 107, 0, 115, 0, 104, 0, 101, 0, 108, 0, 102, 0, 46, 0, 86, 0, 73, 0, 69, 0, 87, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -1, -1, 0, 0, 0, 16, -1, -1, -1, -1, -1, -1, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -1, -1]
if (null != data && 1 < data.length) {
Intent intent = null;
Parcel parcel = Parcel.obtain();
// 进行反序列化:
parcel.unmarshall(data, 0, data.length);
intent = Intent.CREATOR.createFromParcel(parcel);
// intent 内存状态, Intent 反序列化失败.
Intent { (has extras) }
null
null
null
null
null
Bundle[mParcelledData.dataSize=0]
0
null
null
null
null
}
查看Android Intnet 源代码:
看不出来有什么异常
public void writeToParcel(Parcel out, int flags) {
out.writeString(mAction);
Uri.writeToParcel(out, mData);
out.writeString(mType);
out.writeInt(mFlags);
out.writeString(mPackage);
ComponentName.writeToParcel(mComponent, out);
if (mSourceBounds != null) {
out.writeInt(1);
mSourceBounds.writeToParcel(out, flags);
} else {
out.writeInt(0);
}
if (mCategories != null) {
out.writeInt(mCategories.size());
for (String category : mCategories) {
out.writeString(category);
}
} else {
out.writeInt(0);
}
if (mSelector != null) {
out.writeInt(1);
mSelector.writeToParcel(out, flags);
} else {
out.writeInt(0);
}
if (mClipData != null) {
out.writeInt(1);
mClipData.writeToParcel(out, flags);
} else {
out.writeInt(0);
}
out.writeBundle(mExtras);
}
public static final Parcelable.Creator<Intent> CREATOR
= new Parcelable.Creator<Intent>() {
public Intent createFromParcel(Parcel in) {
return new Intent(in);
}
public Intent[] newArray(int size) {
return new Intent[size];
}
};
/** @hide */
protected Intent(Parcel in) {
readFromParcel(in);
}
public void readFromParcel(Parcel in) {
setAction(in.readString());
mData = Uri.CREATOR.createFromParcel(in);
mType = in.readString();
mFlags = in.readInt();
mPackage = in.readString();
mComponent = ComponentName.readFromParcel(in);
if (in.readInt() != 0) {
mSourceBounds = Rect.CREATOR.createFromParcel(in);
}
int N = in.readInt();
if (N > 0) {
mCategories = new HashSet<String>();
int i;
for (i=0; i<N; i++) {
mCategories.add(in.readString().intern());
}
} else {
mCategories = null;
}
if (in.readInt() != 0) {
mSelector = new Intent(in);
}
if (in.readInt() != 0) {
mClipData = new ClipData(in);
}
mExtras = in.readBundle();
}