non-empty constructor issue

Question

i have tried to make a non empty constructor but with no success. the eclipse says :

From the Fragment documentation: Every fragment must have an empty constructor, so it can be instantiated when restoring its activity's state. It is strongly recommended that subclasses do not have other constructors with parameters, since these constructors will not be called when the fragment is re-instantiated; instead, arguments can be supplied by the caller with setArguments(Bundle) and later retrieved by the Fragment with getArguments().

so how can i make a non empty constructor? here is the code :

import java.util.ArrayList;
import java.util.List;
import android.annotation.SuppressLint;
import android.content.Context;
import android.os.Bundle;
import android.app.ListFragment;
import android.app.LoaderManager.LoaderCallbacks;
import android.content.AsyncTaskLoader;
import android.content.Loader;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;


public class MyListFragment extends ListFragment implements
    LoaderCallbacks<Void> {

private static final String TAG = "FragmentTabs";

private String mTag;
private MyAdapter mAdapter;
private ArrayList<String> mItems;
private LayoutInflater mInflater;
private int mTotal;
private int mPosition;

private static final String[] About = { "Lorem", "ipsum", "dolor", "sit",
        "amet", "consectetur", "adipiscing", "elit", "Fusce", "pharetra",
        "luctus", "sodales" };
private static final String[] FAQ = { "I", "II", "III", "IV", "V",
        "VI", "VII", "VIII", "IX", "X", "XI", "XII", "XIII", "XIV", "XV" };
private static final String[] Tips = { "hello" , "bitch" , "ass" , "partners" , "screw", "you" ,"all", "peace" , "out"};

private static final int SLEEP = 1000;

private final int wordBarColor = R.color.word_bar;
private final int numberBarColor = R.color.number_bar;



public MyListFragment(String tag) {
    mTag = tag;
    mTotal = HelpFragment.TAB_About.equals(mTag) ? About.length
            : About.length;

    Log.d(TAG, "Constructor: tag=" + tag);
}

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
    // this is really important in order to save the state across screen
    // configuration changes for example
    setRetainInstance(true);

    mInflater = LayoutInflater.from(getActivity());

    // you only need to instantiate these the first time your fragment is
    // created; then, the method above will do the rest
    if (mAdapter == null) {
        mItems = new ArrayList<String>();
        mAdapter = new MyAdapter(getActivity(), mItems);
    }
    getListView().setAdapter(mAdapter);

    // initiate the loader to do the background work
    getLoaderManager().initLoader(0, null, this);
}

@Override
public Loader<Void> onCreateLoader(int id, Bundle args) {
    AsyncTaskLoader<Void> loader = new AsyncTaskLoader<Void>(getActivity()) {

        @Override
        public Void loadInBackground() {
            try {
                // simulate some time consuming operation going on in the
                // background
                Thread.sleep(SLEEP);
            } catch (InterruptedException e) {
            }
            return null;
        }
    };
    // somehow the AsyncTaskLoader doesn't want to start its job without
    // calling this method
    loader.forceLoad();
    return loader;
}

@Override
public void onLoadFinished(Loader<Void> loader, Void result) {

    // add the new item and let the adapter know in order to refresh the
    // views
    mItems.add(HelpFragment.TAB_About.equals(mTag) ? About[mPosition]
            : FAQ[mPosition]);
    mAdapter.notifyDataSetChanged();

    // advance in your list with one step
    mPosition++;
    if (mPosition < mTotal - 1) {
        getLoaderManager().restartLoader(0, null, this);
        Log.d(TAG, "onLoadFinished(): loading next...");
    } else {
        Log.d(TAG, "onLoadFinished(): done loading!");
    }
}

@Override
public void onLoaderReset(Loader<Void> loader) {
}

private class MyAdapter extends ArrayAdapter<String> {

    public MyAdapter(Context context, List<String> objects) {
        super(context, R.layout.list_item, R.id.text, objects);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View view = convertView;
        Wrapper wrapper;

        if (view == null) {
            view = mInflater.inflate(R.layout.list_item, null);
            wrapper = new Wrapper(view);
            view.setTag(wrapper);
        } else {
            wrapper = (Wrapper) view.getTag();
        }

        wrapper.getTextView().setText(getItem(position));
        wrapper.getBar().setBackgroundColor(
                mTag == HelpFragment.TAB_About ? getResources().getColor(
                        wordBarColor) : getResources().getColor(
                        numberBarColor));
        return view;
    }

}

// use an wrapper (or view holder) object to limit calling the
// findViewById() method, which parses the entire structure of your
// XML in search for the ID of your view
private class Wrapper {
    private final View mRoot;
    private TextView mText;
    private View mBar;

    public Wrapper(View root) {
        mRoot = root;
    }

    public TextView getTextView() {
        if (mText == null) {
            mText = (TextView) mRoot.findViewById(R.id.text);
        }
        return mText;
    }

    public View getBar() {
        if (mBar == null) {
            mBar = mRoot.findViewById(R.id.bar);
        }
        return mBar;
    }
}
}

thanks for any help which will be provided by U.

Answer 1

so how can i make a non empty constructor?

Generally, you don't create a non-empty constructor on a Fragment. Instead, use the factory pattern, as was described in the comments:

  static EditorFragment newInstance(int position) {
    EditorFragment frag=new EditorFragment();
    Bundle args=new Bundle();

    args.putInt(KEY_POSITION, position);
    frag.setArguments(args);

    return(frag);
  }

Your fragment can then retrieve the Bundle via getArguments(), and you can retrieve whatever data you put into that Bundle.