Passing object array using Parcelable object

Question

I am trying to pass array of customized object using Parcelable. I found some discussions in my search like link. I followed these examples and but can't find the implementation for the array of objects. My problem is object becomes null at the new activity. My implementation is as follow.

MY percelable object

    public class showStatisticsObj implements Parcelable{
    public String dt = null;
    public int totalmiles = 0;
    public Date date = null;

    public showStatisticsObj() { ; };

    public showStatisticsObj(Parcel in) { readFromParcel(in); } 

    @Override
    public int describeContents() {
        // TODO Auto-generated method stub
        return 0;
    }
    @Override
    public void writeToParcel(Parcel arg0, int arg1) {
        // TODO Auto-generated method stub
        arg0.writeString(dt); 
        arg0.writeInt(totalmiles);      
    }


    public void readFromParcel(Parcel in) {   
        dt = in.readString(); 
        totalmiles = in.readInt(); 
    } 

    @SuppressWarnings("rawtypes")
    public static final Parcelable.Creator CREATOR = new Parcelable.Creator() { 
        public showStatisticsObj createFromParcel(Parcel in) 
        { 
            return new showStatisticsObj(in); 
        }   
        public showStatisticsObj[] newArray(int size) 
        { 
            return new showStatisticsObj[size]; 
        } 
    }; 

    }


    Parcelable[] passedArray = new Parcelable[totaldifferentDates];
    for (int i=0; i<totaldifferentDates; ++i) {
        passedArray[i] = showStatObj[i];
    }

    Intent displayintent = new Intent(this, DisplayStatistics.class);
    displayintent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    displayintent.putExtra("bundleObj", passedArray);
    startActivity(displayintent);

At the new activity, I extract as

    Bundle bundle = getIntent().getExtras();    
    showStatObjinDisplay = (showStatisticsObj) bundle.getParcelable("bundleObj");

But showStatObjinDisplay is null. What is wrong?Pls help me.

Did you initialize showStatObjinDisplay ? – amalBit Jul 13 '13 at 10:24 — amalBit, Jul 13 '13 at 10:24

Koso · Accepted Answer · 2013-07-13T11:32:00.890

I would try change CREATOR like Minhtdh said.

Next you don't need following code, because you already have parcelable array (showStatisticsObj is Parcelable):

// you don't need following code
Parcelable[] passedArray = new Parcelable[totaldifferentDates];
for (int i=0; i<totaldifferentDates; ++i) {
    passedArray[i] = showStatObj[i];
}

So you just pass showStatObj to intent:

Intent displayintent = new Intent(this, DisplayStatistics.class);
displayintent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
displayintent.putExtra("bundleObj", showStatObj);
startActivity(displayintent);

And finally you get it from bundle like this:

Parcelable[] ps = bundle.getParcelableArrayExtra();
showStatisticsObj[] uri = new showStatisticsObj[ps.length];
System.arraycopy(ps, 0, uri, 0, ps.length);

You passed Parcelable[] so have to search for Parcelable[] in bundle and then convert it to showStatisticsObj[]. In java you can't cast Parcelable[] to showStatisticsObj[].

And as suggestion for you code, class names should always start with uppercase letter. So not showStatisticsObj, but ShowStatisticsObj.

what if we need to use `putParcelable()` ? – Choletski Nov 14 '16 at 10:27 — Choletski, Nov 14 '16 at 10:27

score -4 · Answer 2 · answered Jul 13 '13 at 11:15

it is better to implement Serializable interface. it is easier than Parcelable.

check this sample :

public class Foo implements Serializable
{
    private static final long   serialVersionUID    = -459713774703414626L;
    public String               m_sName;
    public String               m_spass;
    public int                  m_iAge;
    public boolean              m_bUseAgePremissions;
}

In Send

Foo MyObj=new Foo()
Bundle bData=new Bundle();
bData.putSerializable("test", MyObj);
Intent myIntent = ...
myIntent .putExtras(bData);

In Receive

Bundle bDataReceive = myIntent.getExtras();
Foo MyObj = (Foo)bDataReceive.getSerializable("test");

Serializable is frowned upon in Android http://developer.android.com/reference/java/io/Serializable.html — Jon, Jul 13 '13 at 11:45

Passing object array using Parcelable object

2 Answers2