我在发送带有 parcelable 对象的 Intent 时遇到了奇怪的问题。这个对象有一个字符串数组。使用此答案 How to send an object from one Android Activity to another using Intents?我首先将我的对象创建为可打包的,然后发送它。这是我的代码 fragment :
public class MyObject implements Parcelable{
private String _title = null;
private String[] _genre;
private int _time = 0;
private String _disc = null;
private static final String TAG = "MyObject";
public MyObject (String title, String[] genre, int time, String disc) {
_title = title;
_genre = genre;
_time = time;
_disc = disc;
}
public MyObject(Parcel source) {
/*
* Reconstruct from the Parcel
*/
Log.v(TAG, "ParcelData(Parcel source): time to put back parcel data");
_title = source.readString();
try{
source.readStringArray(_genre);
}catch(Exception e){
Log.e(TAG,e.toString());
}
_time = source.readInt();
_disc = source.readString();
}
/*... Getters and setters and other stuff...*/
@Override
public int describeContents() {
// TODO Auto-generated method stub
return 0;
}
@Override
public void writeToParcel(Parcel dest, int flags) {
Log.v(TAG, "writeToParcel..."+ flags);
dest.writeString(_title);
dest.writeStringArray(_genre);
dest.writeInt(_time);
dest.writeString(_disc);
Log.i(TAG,_genre[0]);
}
// this is used to regenerate your object. All Parcelables must have a CREATOR that implements these two methods
public static final Parcelable.Creator<MyObject> CREATOR = new Parcelable.Creator<MyObject>() {
public MyObject createFromParcel(Parcel in) {
return new MyObject(in);
}
public MyObject[] newArray(int size) {
return new MyObject[size];
}
};
}
发送似乎没问题。
Intent displayInfo = new Intent(getApplicationContext(), MovieInfo.class);
displayInfo.putExtra(OBJECT, mySQLiteAdapter.getEntry(idSet));
startActivity(displayInfo);
但是,当我试图获取这些数据时
Intent intent = getIntent();
myParcel = (MyObject) intent.getParcelableExtra(FBM2Activity.OBJECT);
我从 readStringArray 获取 NullPointerException。有谁知道我在哪里可能出错?
最佳答案
使用 _genre = source.createStringArray()
。
这背后的原因是 readStringArray(String[] val)
期望 val
是一个已经创建的 String[]
具有正确数量的数组元素。当您调用 source.readStringArray(_genre)
时,_genre
为 null
。
关于java - 使用 Parcelable 发送 StringArray 时出现 NullPointerException,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/11492942/