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Create a class that contains a custom list of objects

I get an error when creating a list object (I think an error occurred while reading the object) here is my code

public class TestSample implements Parcelable { int intValue; String stirngValue; private List<DocumentControlPolicy> cpls; @Override public int describeContents() { // TODO Auto-generated method stub return 0; } @Override public void writeToParcel(Parcel dest, int flags) { dest.writeInt(intValue); dest.writeString(stirngValue); dest.writeTypedList(cpls); dest.writeList(cpls); } public static final Parcelable.Creator<TestSample> CREATOR = new Parcelable.Creator<TestSample>() { public TestSample createFromParcel(Parcel in) { return new TestSample(in); } public TestSample[] newArray(int size) { return new TestSample[size]; } }; private TestSample(Parcel in) { intValue = in.readInt(); stirngValue=in.readString(); in.readTypedList(cpls,DocumentControlPolicy.CREATOR); } public TestSample(int intValue, String stirngValue) { super(); this.intValue = intValue; this.stirngValue = stirngValue; } }

And here is the code to send data from one activity to another

 Intent nextpage = new Intent(this, Secondpage.class); TestSample tst= new TestSample(1,"Tood"); Log.i("myTag", tst.toString()); nextpage.putExtra("ONE", tst); startActivity(nextpage);

here is the code to get the data

  TestSample tst = getIntent().getParcelableExtra("ONE"); if(tst != null){ Log.i("myTag", "second "+tst.toString()); }else{ Log.i("myTag","second tst is null"); }

But I get the following exception

 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): FATAL EXCEPTION: main 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.app.parceblecheck/com.app.parceblecheck.Secondpage}: java.lang.NullPointerException 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.app.ActivityThread.access$2300(ActivityThread.java:125) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.os.Handler.dispatchMessage(Handler.java:99) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.os.Looper.loop(Looper.java:123) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.app.ActivityThread.main(ActivityThread.java:4627) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at java.lang.reflect.Method.invokeNative(Native Method) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at java.lang.reflect.Method.invoke(Method.java:521) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at dalvik.system.NativeStart.main(Native Method) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): Caused by: java.lang.NullPointerException 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.os.Parcel.readTypedList(Parcel.java:1555) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at com.zenprise.android.policy.TestSample.<init>(TestSample.java:41) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at com.zenprise.android.policy.TestSample.<init>(TestSample.java:38) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at com.zenprise.android.policy.TestSample$1.createFromParcel(TestSample.java:30) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at com.zenprise.android.policy.TestSample$1.createFromParcel(TestSample.java:1) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.os.Parcel.readParcelable(Parcel.java:1906) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.os.Parcel.readValue(Parcel.java:1771) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.os.Parcel.readMapInternal(Parcel.java:2008) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.os.Bundle.unparcel(Bundle.java:208) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.os.Bundle.getParcelable(Bundle.java:1100) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.content.Intent.getParcelableExtra(Intent.java:3396) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at com.app.parceblecheck.Secondpage.onCreate(Secondpage.java:27) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627) 10-28 19:30:58.281: ERROR/AndroidRuntime(3371): ... 11 more
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1 answer

You did not create a cpls object before using it
In your TestSample(Parcel in) cpls , you use cpls without declaring it.
You should do it

  private TestSample(Parcel in) { intValue = in.readInt(); stirngValue=in.readString(); cpls = new ArrayList<DocumentControlPolicy>();//The code you missed.. in.readTypedList(cpls,DocumentControlPolicy.CREATOR); }
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