Develop Reference

Connecting to external database in android

I am trying to connect to my database on my localhost through my android application. I have created a php file and stored it in my wamp/www/myfolder, when I run it it works fine, so it must be a problem with my android class.
public void getData(){
String result ="";
InputStream isr = null;
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://localhost/testdata/getAllCustomers.php");
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
isr = entity.getContent();
}catch(Exception e){
Log.e("log_tag", "Error in http connection");
resultView.setText("Couldnt connect to database");
I have gone over my code many times but I can't find the problem.
I have created two morw try catches in this method that convert the result and the other one parses the data but when I run it the first log appears so it doesn't connect to the database.
P.s I am using eclipse, to I need a plugin for json, I know eclipse IDE supports it.

NetworkOnMainThreadException means that you are attempting to perform a network operation on the main thread, which is forbidden. Simply do it from another thread. This is mainly done by creating an AsyncTask. Here's an example. And here's another one.
It's worth noting that NetworkOnMainThreadException is only thrown for applications targeting the Honeycomb SDK or higher, but the behaviour is always heavily discouraged.

The loopback address in case of android when you are trying to connect from emulator is 10.0.2.2
i.e instead of localhost use 10.0.2.2

Android: HttpClient remote vs. local server

I'm having problems with an app that works when connecting to a remote web server, running a php script against a database. However, when I point the same app to my local web server running on my machine, things doesn't work.
Here's the code I use for connecting to the remote web server (it needs authentication):
(All the networking code is done inside an AsyncTask class.)
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
StringBuilder authentication = new
StringBuilder().append("frankh").append(":").append("vriceI29");
result = Base64.encodeBytes(authentication.toString().getBytes());
httppost.setHeader("Authorization", "Basic " + result);
nameValuePairs.add(new BasicNameValuePair("date", date));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
For the connection to the local server, which doesn't use authentication, I'm commenting out these lines:
//StringBuilder authentication = new
// StringBuilder().append("frankh").append(":").append("vriceI29");
//result = Base64.encodeBytes(authentication.toString().getBytes());
//httppost.setHeader("Authorization", "Basic " + result);
However, I get two different errors, depending on how I phrase the url to the local web server.
If I use this url: "http://localhost.shoppinglistapp/fetchlist.php"
I get this error:
Error in http connectionjava.net.UnknownHostException: localhost.shoppinglistapp
If I skip the http part in the url, I get this error:
Error in http connectionjava.lang.IllegalStateException: Target host must not be null,
or set in parameters.
What am I doing wrong here? The remote server is a Linux Apache server, and the local server is IIS 7. The local server is supposed to be just for working on when I've got no or a bad internet connection, so it's not critical, but I hate not knowing why things doesn't work.

If you testing via your local emulator, you'll want to use 10.0.2.2 instead of 'localhost'.
Referring to localhost from the emulated environment

Android MySQL Connection

I am trying to connection with php-MySQL using below code
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://127.0.0.1/mytable.php");
// HttpPost httppost = new HttpPost("http://localhost/mytable.php");
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
}catch(Exception e){
Log.e("log_tag", "Error in http connection"+e.toString());
}
when control goes on httpclient.execute(httppost); it throws an exception:
org.apache.http.conn.HttpHostConnectException: Connection to http://127.0.0.1 refused
I also add <uses-permission android:name="android.permission.INTERNET" /> to my AndroidManifest.xml file.
When I test my php file directly from a browser, it works fine. Any suggestions?

From the emulator, il you want to access your physical computer, you must use the following IP address :
10.0.2.2
The one you used, 127.0.0.1, points to the machine inside which your code is executed -- i.e. the emulator itself.
As you don't have an HTTP server running on your Android emulator, your application cannot connect to it -- which explains the error message you get.
For more informations, you should read the following section of the manual : Network Address Space

127.0.0.1 is localhost, the current device. On your computer, it refers to your computer, but on a device or an emulator it refers to that device.
See this document on how to refer to the localhost of your computer when running within an emulator. Alternatively, you can change 127.0.0.1 to your computer's actual IP address.
http://developer.android.com/resources/faq/commontasks.html#localhostalias

See entire POST request from Android app

I'm trying to debug a little problem I have with a web service. I cannot POST to the webservice, but I can GET just fine.
When I try to post data to the webservice I get a HTTP 1/1 400 Bad Request.
Is there a way I can see more details?.. I dont have access to the server, on which the webservice is hosted
HTTP Post code
DefaultHttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://lino.herter.dk/Service.svc/Data/");
StringBuilder sb = new StringBuilder();
StringEntity se = new StringEntity("test");
se.setContentType("text/xml");
httppost.setHeader("Content-Type","text/xml");
httppost.setEntity(se);
HttpResponse response2 = httpclient.execute(httppost);
sb = inputStreamToString(response2.getEntity().getContent());

It might be easiest to set up Wireshark on your development machine, and capture the traffic between your Android and the server. You'll have to run Wireshark in Promiscuous mode, which I think is the default option.

Why am I Not able to send http request over WIFI to a machine on the local network from my android device

I am on WIFI and my Android device is connected.
In the android device I open a browser and go to http://192.168.1.12 - This is the IP address of the machine/server on the local network. I get the home page from this machine into my browser on the android device (because there is web server installed and it is a server machine).
Through my Java program - HttpPost is working very well for external sites like http://www.yahoo.com through WIFI - but it is NOT working for a server on the LAN
HttpClient hc = new DefaultHttpClient();
HttpPost post = new HttpPost("http://192.168.0.12/");
HttpResponse rp = hc.execute(post);
The above code DOES NOT work and http response status 404. But if I change the above url to say "http://www.yahoo.com" it works and response status is 200
Can anyone help please

The machine's IP is 192.168.1.12, but you're using HttpPost with 192.168.0.12.