Eu tenho um adaptador com gridview que funciona como uma atividade. Agora estou tentando colocá-lo em um fragmento e convertido as coisas, mas não funciona. Quando incluo o IconFragmentSystem na minha Activity, recebo uma força fechada quando tento abrir a Activity.

Sei que a Atividade funciona porque posso usar outros Fragmentos e está tudo bem, então sei que meu problema está nesse arquivo.

package com.designrifts.ultimatethemeui;
import com.designrifts.ultimatethemeui.R;
import android.content.Context;
import android.content.Intent;
import android.content.res.Resources;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.*;

import java.util.ArrayList;

public class IconFragmentSystem extends Fragment implements AdapterView.OnItemClickListener{
private static final String RESULT_OK = null;
public Uri CONTENT_URI;

public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    View view = inflater.inflate(R.layout.main, container, false);

    super.onCreate(savedInstanceState);
    int iconSize=getResources().getDimensionPixelSize(android.R.dimen.app_icon_size);

    GridView gridview = (GridView) getActivity().findViewById(R.id.icon_grid);
    gridview.setAdapter(new IconAdapter(this, iconSize));
    gridview.setOnItemClickListener(this);
    CONTENT_URI=Uri.parse("content://"+iconsProvider.class.getCanonicalName());
    return view;
}

@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
    String icon=adapterView.getItemAtPosition(i).toString();
    Intent result = new Intent(null, Uri.withAppendedPath(CONTENT_URI,icon));
    setResult(RESULT_OK, result);
    finish();
}
private void setResult(String resultOk, Intent result) {
    // TODO Auto-generated method stub

}

private void finish() {
    // TODO Auto-generated method stub

}
private class IconAdapter extends BaseAdapter{
    private Context mContext;
    private int mIconSize;
    public IconAdapter(Context mContext, int iconsize) {
        super();
        this.mContext = mContext;
        this.mIconSize = iconsize;
        loadIcon();
    }

    public IconAdapter(IconFragmentSystem iconssystem, int iconSize) {
        // TODO Auto-generated constructor stub
    }

    @Override
    public int getCount() {
        return mThumbs.size();
    }

    @Override
    public Object getItem(int position) {
        return mThumbs.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView imageView;
        if (convertView == null) {
            imageView = new ImageView(mContext);
            imageView.setLayoutParams(new GridView.LayoutParams(mIconSize, mIconSize));
        } else {
            imageView = (ImageView) convertView;
        }
        imageView.setImageResource(mThumbs.get(position));
        return imageView;
    }

    private ArrayList<Integer> mThumbs;
    ////////////////////////////////////////////////
    private void loadIcon() {
        mThumbs = new ArrayList<Integer>();

        final Resources resources = getResources();
        final String packageName = getActivity().getApplication().getPackageName();

        addIcon(resources, packageName, R.array.systemicons);

    }
    private void addIcon(Resources resources, String packageName, int list) {
        final String[] extras = resources.getStringArray(list);
        for (String extra : extras) {
            int res = resources.getIdentifier(extra, "drawable", packageName);
            if (res != 0) {
                final int thumbRes = resources.getIdentifier(extra,"drawable", packageName);
                if (thumbRes != 0) {
                    mThumbs.add(thumbRes);
                }
            }
            }
           }
        }
    }

Eu tentei maneiras diferentes de implementar isso, mas todas falharam e eu realmente poderia usar a ajuda para me indicar a direção certa.

Este é o meu xml no layout

    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >           
  <GridView
    android:id="@+id/gridview"
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent"
    android:columnWidth="90dp"
    android:numColumns="auto_fit"
    android:verticalSpacing="10dp"
    android:horizontalSpacing="10dp"
    android:stretchMode="columnWidth"
    android:gravity="center"
/>

    </RelativeLayout>