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How to send an object from one Android Activity to another using Intents?

在 Activity 之間傳遞引數的方法:

If you’re just passing objects around then Parcelable was designed for this. It requires a little more effort to use than using Java’s native serialization, but it’s way faster (and I mean way, WAY faster).

From the docs, a simple example for how to implement is:

// simple class that just has one member property as an example
public class MyParcelable implements Parcelable { private int mData; /* everything below here is for implementing Parcelable */ // 99.9% of the time you can just ignore this @Override public int describeContents() { return 0; } // write your object's data to the passed-in Parcel
@Override public void writeToParcel(Parcel out, int flags) { out.writeInt(mData); } // this is used to regenerate your object. All Parcelables must have a CREATOR that implements these two methods public static final Parcelable.Creator<MyParcelable> CREATOR =
new Parcelable.Creator<MyParcelable>() { public MyParcelable createFromParcel(Parcel in) { return new MyParcelable(in); } public MyParcelable[] newArray(int size) { return new MyParcelable[size]; } }; // example constructor that takes a Parcel and gives you an object populated with it's values private MyParcelable(Parcel in) { mData = in.readInt(); } }

Observe that in the case you have more than one field to retrieve from a given Parcel, you must do this in the same order you put them in (that is, in a FIFO approach).

Once you have your objects implement Parcelable it’s just a matter of putting them into your Intents with putExtra():

Intent i = new Intent();
i.putExtra("name_of_extra", myParcelableObject);

Then you can pull them back out with getParcelableExtra():

Intent i = getIntent();
MyParcelable myParcelableObject = (MyParcelable) i.getParcelableExtra("name_of_extra");

If your Object Class implements Parcelable and Serializable then make sure you do cast to one of the following:

i.putExtra("parcelable_extra", (Parcelable) myParcelableObject);
i.putExtra("serializable_extra", (Serializable) myParcelableObject);

You can send serializable object through intent

// send where details is object
ClassName details = new ClassName();
Intent i = new Intent(context, EditActivity.class);
i.putExtra("Editing", details);
startActivity(i);


//receive
ClassName model = (ClassName) getIntent().getSerializableExtra("Editing");

And 

Class ClassName implements Serializable {
} 
//To pass:
intent.putExtra("MyClass", obj);

// To retrieve object in second Activity
getIntent().getSerializableExtra("MyClass");