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javaandroidarraylistonactivityresult

Passing ArrayList<Object> back to main Activity (Android)


I have an ArrayList< Object> where the Object is an instance of a class I made. I want to pass this new array list back to the main activity to put it in a navigationdrawer item.

How do I pass an ArrayList< Object> from an activity back to the main one?

I have tried the bundle.getParcelableArrayList however it tells me that "Inferred type Object for type parameter T is not within its bounds, should implement android.os.parcelable"

Here is my Code:

public void createPlaylist(String playlistName, ArrayList<Song> newPlaylistSongsArray) {
    Intent returnIntent = new Intent();
    Bundle b = new Bundle();
    b.putParcelableArrayList("array", (ArrayList<? extends Parcelable>) newPlaylistSongsArray);
    returnIntent.putExtra("playListName", playlistName);
    returnIntent.putExtra("array", newPlaylistSongsArray);
    setResult(Activity.RESULT_OK,returnIntent);
    finish();
}

And:

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == 1) {
        if (resultCode == Activity.RESULT_OK){
            String newPlaylistName = data.getStringExtra("playListName");
            Bundle b = getIntent().getExtras();
            final ArrayList<Song> newPlaylist = b.getParcelableArrayList("array");
            Toast.makeText(MP3Player.this, "New Playlist Created", Toast.LENGTH_LONG).show();
        }
        if (resultCode == Activity.RESULT_CANCELED) {
            Toast.makeText(MP3Player.this, "Shit went wrong yo!", Toast.LENGTH_LONG).show();
        }
    }
}

Solution

  • For the easiest way, your Song class need implement Serializable.

    Bundle bundle = new Bundle();
    bundle.putSerializable("newPlaylist", newPlaylist);
    intent.putExtras(bundle);
    

    in other activity:

    Intent intent = this.getIntent();
    Bundle bundle = intent.getExtras();
    
    ArrayList<Song> newPlaylist=
                   (ArrayList<Song>)bundle.getSerializable("newPlaylist");