我在android中还是新手，所以我对parcelable有点迷惑。所以这是我的问题： 我有3个班，分别是A，B，C。 B和C都从A 扩展。 我已经实现了其中三个＆＃34; Parcelable＆＃34;并且具有来自A的所有属性.B和C还具有A类旁边的另一个属性。
所以在我的MainActivity中，我想分开包装它们，因为首先我想让 A作为默认来使用并将数据加载到另一个活动，但是在另一个活动中，我向用户提供了一些选项，无论他们是否仍想使用A的数据，或者想要将其更改为B或C的数据。
首先，我认为用户将无法返回主要活动（因此实际上有超过2个活动）。我打算从MainActivity传递B和C的数据，所以我不需要再次调用它。
这是我的代码： A类（父母）
public class A implements Parcelable{
private String name;
private int lvl;
private String job;
public A (String name, int lvl, String job)
{
this.name = name;
this.lvl = lvl;
this.job = job;
}
//setter & getter
public void setName (String name) {this.name = name;}
public String getName () {return name;}
public void setLvl (int lvl) {this.lvl = lvl;}
public int getLvl () {return lvl;}
public void setJob (String job) {this.job = job;}
public String getJob () {return job;}
//Parcelable
protected A (Parcel source)
{
this.name = source.readString ();
this.lvl = source.readInt ();
this.job = source.readString ();
}
public static final Parcelable.Creator<A> CREATOR = new Parcelable.Creator<A>()
{
public A createFromParcel (Parcel source) {return new A(source);}
public A[] newArray (int size) {return new A[size];}
};
@Override
public int describeContents () {return 0;}
@Override
public void writeToParcel (Parcel source, int flags)
{
source.writeString (name);
source.writeInt (lvl);
source.writeString (job);
} }
这是B和C代码（实际上它们具有相同的属性。只有它们的工作名称彼此不同）
public class B extends A implements Parcelable
{
private int job_lvl;
private int exp;
//constructor
B (String name, int lvl, String job, int job_lvl, int exp)
{
super (name, lvl, job);
this.job_lvl = job_lvl;
this.exp = exp;
}
public void setJob_lvl (int job_lvl) {this.job_level = job_lvl;}
public int getJob_lvl () {return job_lvl;}
public void setExp (int exp) {this.exp = exp;}
public int getExp () {return exp;}
//Parcelable
protected B (Parcel source)
{
super (source);
job_lvl = source.readInt();
exp = source.readInt();
}
@Override
public void writeToParcel (Parcel source, int flags)
{
source.writeInt (job_lvl);
source.writeInt (exp);
}
@Override
public int describeContents () {return 0;}
public static final Parcelable.Creator<B> CREATOR = new Parcelable.Creator<B>()
{
@Override
public B createFromParcel(Parcel source) {return new B(source);}
@Override
public B[] newArray(int size) {return new B[size[];}
};
}
：
public class MainActicity extends Activity
{
Bundle bundle = new Bundle();
A a;
B b;
//C c;
String name;
@Override
protected void onCreate (Bundle saveInstanceState)
{
super.onCreate(savedInstanceState);
//getText from user (input their name)
//Name -> EditText
name = Name.getText().toString();
a = new A("", 1, "Novice");
a.setName(name);
//B (name, lvl, job, job_lvl, exp)
bundle = new B(a.getName(), a.getLvl(), "Swordman", 1, 0);
bundle.putParcelable ("Player", a);
bundle.putParcelable ("Swordman", b);
startActivity(new Intent(MainActivity.this,SecondActivity).putExtras(bundle));
finish();
}
}
：
public class SecondActicity extends Activity
{
Bundle bundle;
A a;
B b;
//C c;
@Override
protected void onCreate (Bundle saveInstanceState)
{
super.onCreate(savedInstanceState);
bundle = getIntent().getExtras();
a = bundle.getParcelable ("Player");
//Displaying data from class A because it is a default
//user make a choice in here whether they want to change their job or not
//if they want to change then from class A change to class B's data
if (//choose to become swordman)
{
b = bundle.getParcelable ("Swordman");
//showing the data from class B
//change all the activities which require A,B,C's data that depend on user's choice
}
}
}
我在这段代码中遇到错误：
a = bundle.getParcelable ("Player");
错误说：
FATAL EXCEPTION: main
Process: danbin.game, PID: 15577
java.lang.RuntimeException: Unable to start activity ComponentInfo{danbin.game/danbin.game.SecondActivity}: java.lang.RuntimeException: Parcel android.os.Parcel@25a544dc: Unmarshalling unknown type code 6357079 at offset 212
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2379)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2442)
at android.app.ActivityThread.access$800(ActivityThread.java:156)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1351)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:211)
at android.app.ActivityThread.main(ActivityThread.java:5373)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1020)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:815)
Caused by: java.lang.RuntimeException: Parcel android.os.Parcel@25a544dc: Unmarshalling unknown type code 6357079 at offset 212
at android.os.Parcel.readValue(Parcel.java:2259)
at android.os.Parcel.readArrayMapInternal(Parcel.java:2516)
at android.os.BaseBundle.unparcel(BaseBundle.java:221)
at android.os.Bundle.getParcelable(Bundle.java:755)
at android.content.Intent.getParcelableExtra(Intent.java:5089)
at danbin.game.PlayActivity.onCreate(SecondActivity.java:15)
at android.app.Activity.performCreate(Activity.java:5990)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2332)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2442)
at android.app.ActivityThread.access$800(ActivityThread.java:156)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1351)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:211)
at android.app.ActivityThread.main(ActivityThread.java:5373)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1020)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:815)
我真的很感谢你的帮助！ 谢谢