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    <p>If you're just passing objects around then <a href="http://developer.android.com/reference/android/os/Parcelable.html" rel="noreferrer">Parcelable</a> 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, <strong><em>WAY</em></strong> faster).</p> <p>From the docs, a simple example for how to implement is:</p> <pre><code>// 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&lt;MyParcelable&gt; CREATOR = new Parcelable.Creator&lt;MyParcelable&gt;() { 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(); } } </code></pre> <p>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).</p> <p>Once you have your objects implement <code>Parcelable</code> it's just a matter of putting them into your <a href="http://developer.android.com/reference/android/content/Intent.html" rel="noreferrer">Intents</a> with <a href="http://developer.android.com/reference/android/content/Intent.html#putExtra%28java.lang.String,%20android.os.Parcelable%29" rel="noreferrer">putExtra()</a>:</p> <pre><code>Intent i = new Intent(); i.putExtra("name_of_extra", myParcelableObject); </code></pre> <p>Then you can pull them back out with <a href="http://developer.android.com/reference/android/content/Intent.html#getParcelableExtra%28java.lang.String%29" rel="noreferrer">getParcelableExtra()</a>:</p> <pre><code>Intent i = getIntent(); MyParcelable myParcelableObject = (MyParcelable) i.getParcelableExtra("name_of_extra"); </code></pre> <p>If your Object Class implements Parcelable and Serializable then make sure you do cast to one of the following:</p> <pre><code>i.putExtra("parcelable_extra", (Parcelable) myParcelableObject); i.putExtra("serializable_extra", (Serializable) myParcelableObject); </code></pre>
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    1. POHow to send an object from one Android Activity to another using Intents?
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    1. USJeremy Logan
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    1. COHow would this be implemented where mData is an object (e.g. JSONObject) and not an int?
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      1. USPeter Ajtai
    2. COParcel has other methods for writing data types such as strings. In the case of a JSONObject you could put it back to JSON and write it as a String. If the object is Serializable and you don't have the access to make it Parcelable, maybe you could serialize it and deserialize it when you unparcel the top-level object? I haven't done this before, just a guess.
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      1. USRob Lourens
    3. COWhy can't just pass the object without all this? We want to pass an object that is already in memory.
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