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POAndroid passing an arraylist back to parent activity
 

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    <p>I've been searching for a simple example of this with no luck.</p> <p>In my android application I have two activities: 1. The main activity which is launched at startup 2. A second activity which is launched by pressing a button on the main activty.</p> <p>When the second activity is finished (by pressing a button) I want it to send back an ArrayList of type MyObject to the main activity and close itself, which the main activity can then do whatever with it. How would I go about achieving this? I have been trying a few things but it is crashing my application when I start the second activity.</p> <p>When the user presses button to launch second activity:</p> <pre><code> Intent i = new Intent(MainActivity.this, secondactivity.class); startActivityForResult(i, 1); </code></pre> <p>The array which is bundled back after pressing a button on the second activity:</p> <pre><code>Intent intent= getIntent(); Bundle b = new Bundle(); b.putParcelableArrayList("myarraylist", mylist); intent.putExtras(b); setResult(RESULT_OK, intent); finish(); </code></pre> <p>And finally a listener on the main activity (although I'm not sure of 100% when this code launches...)</p> <pre><code> protected void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); if(resultCode==RESULT_OK &amp;&amp; requestCode==1){ Bundle extras = data.getExtras(); final ArrayList&lt;MyObject&gt; mylist = extras.getParcelableArrayList("myarraylist"); Toast.makeText(MainActivity.this, mylist.get(0).getName(), Toast.LENGTH_SHORT).show(); } } </code></pre> <p>Any ideas where I am going wrong? The onActivityResult() seems to be crashing my application.</p> <p>EDIT: Class with parcelable methods:</p> <pre><code>import android.os.Parcel; import android.os.Parcelable; public class Plan implements Parcelable{ private String name; private String id; public Plan(){ } public Plan createFromParcel(Parcel in) { Plan plan = new Plan(); plan.setId(in.readString()); plan.setName(in.readString()); return plan; } public Plan(String name, String id){ this.name = name; this.id = id; } public String getName(){ return name; } public void setName(String name){ this.name = name; } public String getId(){ return id; } public void setId(String id){ this.id = id; } public String toString(){ return "Plan ID: " + id + " Plan Name: " + name; } @Override public int describeContents() { // TODO Auto-generated method stub return 0; } @Override public void writeToParcel(Parcel dest, int flags) { dest.writeString(id); dest.writeString(name); } public static final Parcelable.Creator&lt;Plan&gt; CREATOR = new Parcelable.Creator&lt;Plan&gt;() { public Plan createFromParcel(Parcel in) { return new Plan(); } @Override public Plan[] newArray(int size) { // TODO Auto-generated method stub return new Plan[size]; } }; } </code></pre> <p>After the second activity finished, onactivityresult is called, but nothing displays inside the toast, its blank. any ideas? I'm guessing my class is still messed up...</p> <p>EDIT: got it to work</p> <p>I had the method that Peter supplied in the wrong place. It should be inside creator, like this:</p> <pre><code>public static final Parcelable.Creator&lt;Plan&gt; CREATOR = new Parcelable.Creator&lt;Plan&gt;() { public Plan createFromParcel(Parcel in) { Plan plan = new Plan(); plan.setId(in.readString()); plan.setName(in.readString()); return plan; } </code></pre> <p>and not out on its own.</p> <p>Many thanks to Peter! Hope this helps someone else.</p>
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    1. COcould you please provide some Logcat output? Also, you say that *starting* the second activity crashes your app. Could there be another problem?
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