Pass ArrayList<? implements Parcelable> to Activity

Adrian Jandl picture Adrian Jandl · Feb 28, 2013 · Viewed 60.2k times · Source

I have searched a few topics but not found a solution to my problem.

public class Series implements Parcelable {
private String name;
private int numOfSeason;
private int numOfEpisode;

/** Constructors and Getters/Setters have been removed to make reading easier **/

public Series(Parcel in) {
    String[] data = new String[3];
    in.readStringArray(data);
    this.name = data[0];
    this.numOfSeason = Integer.parseInt(data[1]);
    this.numOfEpisode = Integer.parseInt(data[2]);
}


@Override
public int describeContents() {
    return 0;
}

@Override
public void writeToParcel(Parcel dest, int flags) {
    dest.writeStringArray(new String[] { this.name,
            String.valueOf(this.numOfSeason),
            String.valueOf(this.numOfEpisode) });

}

private void readFromParcel(Parcel in) {
    name = in.readString();
    numOfSeason = in.readInt();
    numOfEpisode = in.readInt();
}

public static final Parcelable.Creator CREATOR = new Parcelable.Creator() {
    @Override
    public Series createFromParcel(Parcel in) {
        return new Series(in);
    }

    @Override
    public Series[] newArray(int size) {
        return new Series[size];
    }
};

}

In my MainActivity I have an ArrayList. To make the list dynamically editeable I need to pass it to another activity where I can edit it.

ArrayList<Series> listOfSeries = new ArrayList<Series>();

    public void openAddActivity() {
    Intent intent = new Intent(this, AddActivity.class);
    intent.putParcelableArrayListExtra(
            "com.example.episodetracker.listofseries",
            (ArrayList<? extends Parcelable>) listOfSeries);
    startActivity(intent);
}

I need to cast the list, otherwise Eclipse gives me the following Error message. The method putParcelableArrayListExtra(String, ArrayList) in the type Intent is not applicable for the arguments (String, List)

Is this the correct way to do it?

    ArrayList<Series> list = savedInstanceState
            .getParcelableArrayList("com.example.episodetracker.listofseries");

This is the way I try to read the data in another activity.

It's crashing on the line above. namely the getParcelableArrayList part.

Answer

snowCrabs picture snowCrabs · Feb 28, 2013
  • The problem is in writing out to the parcel and reading in from the parcel ...

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeString(name);
        dest.writeInt(numOfSeason);
        dest.writeInt(numOfEpisode);
    }
    
    private void readFromParcel(Parcel in) {
        name = in.readString();
        numOfSeason = in.readInt();
        numOfEpisode = in.readInt();
    }
    
  • What you write out has to match what you read in...

    @Override
     protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    
    Intent i = new Intent(this,SecondActivity.class);
    
    ArrayList<testparcel> testing = new ArrayList<testparcel>();
    
    i.putParcelableArrayListExtra("extraextra", testing);
    startActivity(i);
    }
    
        /**********************************************/
    
    
    public class SecondActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    
        ArrayList<testparcel> testing = this.getIntent().getParcelableArrayListExtra("extraextra");
     }
    }
    
  • The above code is having onCreate() from two different activities. The first one launches the second one; and it works fine I was able to pull the parcelable without issue.