我正试图在平台2.2 Froyo上建安安安。 该仪器应与一个远程服务器连接,从该服务器中取回数据,并用不同语言显示用户。

• So my question - What technologies I need to learn so that I can build the above app.

注——我已经安装了“安”平台,并建造了像Hello这样的简单像。 我知道 Java。 我也在使用Eclipse。

感谢你的答复。 评注

页: 1 利用吉大港山区议定书连接网络的守则 页: 1

package in.androidbook.Networking;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.os.Bundle;
import android.widget.ImageView;
import android.widget.Toast;

public class MainActivity extends Activity 
{
    ImageView img;
    /* This is for making asynchronous calls to ensure that connection to server will not return until data is received */

    private class BackgroundTask extends AsyncTask<String, Void, Bitmap>
    {
        protected Bitmap doInBackground(String...url)
        {
            Bitmap bitmap = DownloadImage(url[0]);
            return bitmap;
        }

        protected void onPostExecute(Bitmap bitmap)
        {
            ImageView img = (ImageView) findViewById(R.id.img);
            img.setImageBitmap(bitmap);         
        }
    }
    // Code for making HTTP connection
    private InputStream OpenHttpConnection(String urlString) throws IOException 
    {
        InputStream in = null;
        int response = -1;

        URL url = new URL(urlString);//We take an object of class URL
        URLConnection conn = url.openConnection(); //Create a connection object and open the connection

        if(!(conn instanceof HttpURLConnection)) throw new IOException("Not an Http connection");
        try
        {
            HttpURLConnection httpConn = (HttpURLConnection) conn; //httpConn object is assigned the value of conn. Typecasting is done to avoid conflict.
            httpConn.setAllowUserInteraction(false);
            httpConn.setInstanceFollowRedirects(true);
            httpConn.setRequestMethod("GET");
            httpConn.connect();
            response = httpConn.getResponseCode();

            if(response == HttpURLConnection.HTTP_OK)
                in = httpConn.getInputStream();
        }
        catch (Exception ex)
        {
            throw new IOException("Error connecting");
        }
        return in;
    }   
        //------------------------------------------ OpenHttpConnection method completed----------------------------------------------------------//
    //----------------------------------------------------------------------------------------------------------------------------------------------------------------//
    //-------------------------------Method to download an image--------------------------------------------------------------------------------------//
    private Bitmap DownloadImage(String URL)
    {
        Bitmap bitmap = null;
        InputStream in = null;
        try
        {
            in = OpenHttpConnection(URL);
            bitmap = BitmapFactory.decodeStream(in);
            in.close();
        }
        catch(IOException e1)
        {
            Toast.makeText(this, e1.getLocalizedMessage(), Toast.LENGTH_LONG).show();
            //Toast displays a short msg to user. this refers to current object.
            e1.printStackTrace();
        }
        return bitmap;
    }  


/** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

       Bitmap bitmap = DownloadImage("http://i.zdnet.com/blogs/3-29-androids.jpg");
        img = (ImageView) findViewById(R.id.img);
        img.setImageBitmap(bitmap);
    }
}