Hola, me presento, acabo de iniciarme en el desarrollo de aplicaciones android en eclipse, he creado dos layout, uno principal con un boton que he instanciado a otro layout que realiza una entrada a una base de datos mediante la obtención de unos textos.
Envio los codigos:
El principal:
package com.example.stock;
import android.support.v7.app.ActionBarActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class Principal extends ActionBarActivity {
private Button boton;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_principal);
// Instanciar elemento
boton = (Button) findViewById(R.id.botonEntradas);
// Accion del boton
boton.setOnClickListener(new OnClickListener() {
//@Override
public void onClick(View v) {
Intent intent = new Intent(Principal.this, Entrada.class);
startActivity(intent);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.principal, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
El de la entrada:
package com.example.stock;
import android.support.v7.app.ActionBarActivity;
import java.io.IOException;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.BasicResponseHandler;
import org.apache.http.impl.client.DefaultHttpClient;
import android.annotation.SuppressLint;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
//@SuppressLint("ShowToast")
public class Entrada extends ActionBarActivity {
final EditText codigo=(EditText)findViewById(R.id.codigoText);
final EditText ubicacion=(EditText)findViewById(R.id.ubicacionTex t);
final EditText unidades=(EditText)findViewById(R.id.cantidadText) ;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_entrada);
Button botonEntrada=(Button)findViewById(R.id.botonEntrad as);
botonEntrada.setOnClickListener(new View.OnClickListener() {
@SuppressLint("ShowToast") @Override
public void onClick(View v) {
try{
httpGetData("http://10.0.2.2/registrarArticulo.php?codigo="+codigo.getText()+
"&ubicacion="+ubicacion.getText()+"&unidades="+uni dades.getText());
Toast.makeText(getApplicationContext(), "El dato ha sido enviado correctamente", 1000).show();
}catch(Exception e){
Toast.makeText(getApplicationContext(), "Error en el envio de la informacion, verifique su conexion a internet y vuelva a intentarlo.", 1000).show();
}
}
});
}
public String httpGetData(String mURL) {
String response="";
mURL=mURL.replace(" ", "%20");
Log.i("LocAndroid Response HTTP Threas","Ejecutando get 0: "+mURL);
HttpClient httpclient = new DefaultHttpClient();
Log.i("LocAndroid Response HTTP Thread","Ejecutando get 1");
HttpGet httppost = new HttpGet(mURL);
Log.i("LocAndroid Response HTTP Thread","Ejecutando get 2");
try {
Log.i("LocAndroid Response HTTP","Ejecutando get");
// Execute HTTP Post Request
ResponseHandler<String> responseHandler=new BasicResponseHandler();
response = httpclient.execute(httppost,responseHandler);
Log.i("LocAndroid Response HTTP",response);
} catch (ClientProtocolException e) {
Log.i("LocAndroid Response HTTP ERROR 1",e.getMessage());
// TODO Auto-generated catch block
} catch (IOException e) {
Log.i("LocAndroid Response HTTP ERROR 2",e.getMessage());
// TODO Auto-generated catch block
}
return response;
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.entrada, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
El error que me da en el logCat:
09-25 20:12:04.570: D/AudioManager(9123): [AudioManager.java:471:<init>()] isMicrophoneMute // is_btsco_muted:false Mute:true
09-25 20:12:04.617: D/AndroidRuntime(9123): Shutting down VM
09-25 20:12:04.617: W/dalvikvm(9123): threadid=1: thread exiting with uncaught exception (group=0x4001a560)
09-25 20:12:04.625: E/AndroidRuntime(9123): FATAL EXCEPTION: main
09-25 20:12:04.625: E/AndroidRuntime(9123): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.stock/com.example.stock.Entrada}: java.lang.NullPointerException
09-25 20:12:04.625: E/AndroidRuntime(9123): at android.app.ActivityThread.performLaunchActivity(A ctivityThread.java:1580)
09-25 20:12:04.625: E/AndroidRuntime(9123): at android.app.ActivityThread.handleLaunchActivity(Ac tivityThread.java:1674)
09-25 20:12:04.625: E/AndroidRuntime(9123): at android.app.ActivityThread.access$1500(ActivityThr ead.java:117)
09-25 20:12:04.625: E/AndroidRuntime(9123): at android.app.ActivityThread$H.handleMessage(Activit yThread.java:942)
09-25 20:12:04.625: E/AndroidRuntime(9123): at android.os.Handler.dispatchMessage(Handler.java:99 )
09-25 20:12:04.625: E/AndroidRuntime(9123): at android.os.Looper.loop(Looper.java:130)
09-25 20:12:04.625: E/AndroidRuntime(9123): at android.app.ActivityThread.main(ActivityThread.jav a:3694)
09-25 20:12:04.625: E/AndroidRuntime(9123): at java.lang.reflect.Method.invokeNative(Native Method)
09-25 20:12:04.625: E/AndroidRuntime(9123): at java.lang.reflect.Method.invoke(Method.java:507)
09-25 20:12:04.625: E/AndroidRuntime(9123): at com.android.internal.os.ZygoteInit$MethodAndArgsCa ller.run(ZygoteInit.java:860)
09-25 20:12:04.625: E/AndroidRuntime(9123): at com.android.internal.os.ZygoteInit.main(ZygoteInit .java:618)
09-25 20:12:04.625: E/AndroidRuntime(9123): at dalvik.system.NativeStart.main(Native Method)
09-25 20:12:04.625: E/AndroidRuntime(9123): Caused by: java.lang.NullPointerException
09-25 20:12:04.625: E/AndroidRuntime(9123): at android.app.Activity.findViewById(Activity.java:16 52)
09-25 20:12:04.625: E/AndroidRuntime(9123): at com.example.stock.Entrada.<init>(Entrada.java:24)
09-25 20:12:04.625: E/AndroidRuntime(9123): at java.lang.Class.newInstanceImpl(Native Method)
09-25 20:12:04.625: E/AndroidRuntime(9123): at java.lang.Class.newInstance(Class.java:1409)
09-25 20:12:04.625: E/AndroidRuntime(9123): at android.app.Instrumentation.newActivity(Instrument ation.java:1021)
09-25 20:12:04.625: E/AndroidRuntime(9123): at android.app.ActivityThread.performLaunchActivity(A ctivityThread.java:1572)
09-25 20:12:04.625: E/AndroidRuntime(9123): ... 11 more
Una ayudita plissss.