Apps android studio database

[jose1988]

hi
Im new in android studio,
I´m trying to send to a db but it not works and i dont know why. when i click the button it does nothing.
can somebody help?
thanks
my code:

import java.io.IOException;
    import java.io.UnsupportedEncodingException;
    import java.util.ArrayList;
    import java.util.List;

    import org.apache.http.NameValuePair;
    import org.apache.http.client.ClientProtocolException;
    import org.apache.http.client.HttpClient;
    import org.apache.http.client.entity.UrlEncodedFormEntity;
    import org.apache.http.client.methods.HttpPost;
    import org.apache.http.impl.client.DefaultHttpClient;
    import org.apache.http.message.BasicNameValuePair;

    import android.app.Activity;
    import android.content.pm.ActivityInfo;
    import android.os.AsyncTask;
    import android.os.Bundle;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.EditText;
    import android.widget.ImageButton;
    import android.widget.Toast;


    public class WebService extends Activity  {
        private EditText dni;
        private EditText nombre;
        private EditText telefono;
        private EditText email;
        private Button insertar;
        private Button mostrar;
        private ImageButton mas;
        private ImageButton menos;
      
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR_PORTRAIT);
            setContentView(R.layout.fragment2);

            dni=(EditText)findViewById(R.id.dni);
            nombre=(EditText)findViewById(R.id.nombre);
            telefono=(EditText)findViewById(R.id.telefono);
            email=(EditText)findViewById(R.id.email);      
            insertar=(Button)findViewById(R.id.insertar);
            insertar.setOnClickListener(new OnClickListener(){

                @Override
                public void onClick(View v) {
                    // TODO Auto-generated method stub
                    if(!dni.getText().toString().trim().equalsIgnoreCase("")||
                      !nombre.getText().toString().trim().equalsIgnoreCase("")||
                      !telefono.getText().toString().trim().equalsIgnoreCase("")||
                      !email.getText().toString().trim().equalsIgnoreCase(""))  
                      
                        new Insertar(WebServiceExample.this).execute();      
                  
                    else
                        Toast.makeText(WebServiceExample.this, "Hay informaci�n por rellenar", Toast.LENGTH_LONG).show();
                }
              
            });
          
        }
      
            private boolean insertar(){    
                HttpClient httpclient;
                List<NameValuePair> nameValuePairs;
                HttpPost httppost;
               httpclient=new DefaultHttpClient();
               httppost= new HttpPost("http://localhost/insert.php");
               nameValuePairs = new ArrayList<NameValuePair>(4);
               nameValuePairs.add(new BasicNameValuePair("dni",dni.getText().toString().trim()));
               nameValuePairs.add(new BasicNameValuePair("nombre",nombre.getText().toString().trim()));
               nameValuePairs.add(new BasicNameValuePair("telefono",telefono.getText().toString().trim()));
               nameValuePairs.add(new BasicNameValuePair("email",email.getText().toString().trim()));

                try {
                  httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
                  httpclient.execute(httppost);
                  return true;
                } catch (UnsupportedEncodingException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (ClientProtocolException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                return false;
            }      
            class Insertar extends AsyncTask<String,String,String>{
              
                private Activity context;
              
                Insertar(Activity context){
                    this.context=context;
                }
                @Override
                protected String doInBackground(String... params) {
                    // TODO Auto-generated method stub
                    if(insertar())
                        context.runOnUiThread(new Runnable(){
                            @Override
                            public void run() {
                                // TODO Auto-generated method stub                          
                                Toast.makeText(context, "Persona insertada con �xito", Toast.LENGTH_LONG).show();
                                nombre.setText("");
                                dni.setText("");
                                telefono.setText("");
                                email.setText("");
                            }                      
                        });
                    else
                        context.runOnUiThread(new Runnable(){
                            @Override
                            public void run() {
                                // TODO Auto-generated method stub                          
                                Toast.makeText(context, "Persona no insertada con �xito", Toast.LENGTH_LONG).show();
                            }                  
                        });
                     return null;
                }          
            }
    }