android,arrays,gridview , Blank screen on GridView

Blank screen on GridView


Tag: android,arrays,gridview

I'm trying to create a GridView with an array of strings. These are XML, and MainActivity and Adapter, but what I get is a blank screen. I'm change the background, but the result is the same, but clicking on a point on the screen appears to me the toast stating that the number has been selected. Any thoughts ?


    GridView xmlns:android=""
   xmlns:tools="" android:layout_width="match_parent"


    package kangel.customtest;

import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.GridView;
import android.widget.Toast;

public class MainActivity extends ActionBarActivity {
    GridView gridView;

    protected void onCreate(Bundle savedInstanceState) {
        gridView = (GridView)findViewById(;
        gridView.setAdapter(new NumberAdapter(this));
        gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                Toast.makeText(getBaseContext(),"Hai selezionato il numero "+position, Toast.LENGTH_LONG).show();


    package kangel.customtest;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.TextView;

 * Created by Andrea on 22/06/2015.
public class NumberAdapter extends BaseAdapter {

    private Context context;
    private String numeriGiocabili[]=

    public NumberAdapter(Context context){
        this.context = context;
    public int getCount() {
        return numeriGiocabili.length;

    public Object getItem(int position) {
        return null;

    public long getItemId(int position) {
        return 0;

    public View getView(int position, View convertView, ViewGroup parent) {
        TextView numberView;

        if (convertView == null){
            numberView = new TextView(context);
            numberView.setLayoutParams(new GridView.LayoutParams(80, 80));
            numberView.setPadding(8, 8, 8, 8);
        else {
            numberView = (TextView) convertView;

        return numberView;



I executed ur code. Just add


and it will work! :)


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