Copy & Paste the below code to drawable folder to create attractive buttons

<?xml version="1.0" encoding="UTF-8"?>

<shape  xmlns:android="http://schemas.android.com/apk/res/android"

            android:shape="rectangle">

                            <gradient 

            android:startColor="@color/btngreen"

            android:endColor="@color/btngreen1"

            android:angle="90"

         />

        <corners    android:bottomLeftRadius="5dip"

                android:topRightRadius="5dip"

                android:topLeftRadius="5dip"

                android:bottomRightRadius="5dip"/>

</shape>

Then in your layout Button field, set background for button & see the attractive buttons thru xml

        <Button
            android:id="@+id/attractivebtn"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:clickable="true"
            android:gravity="center"
            android:paddingLeft="15dp"
            android:paddingRight="15dp"
            android:paddingTop="8dp"
            android:paddingBottom="8dp"
            android:textColor="#ffffff"
            android:background="@drawable/btn_bgg"
            android:text="Button" />

Now you get attractive buttons.

You need to create fonts folder under assets folder in your project and put your TTF files into it. Then in your Activity onCreate()

Typeface typeface = Typeface.createFromAsset(this.getAssets(), "fonts/Roboto-Bold.ttf");

                                (or)

Context context=this;

Typeface typeface = Typeface.createFromAsset(context.getAssets(), "fonts/Roboto-Bold.ttf");

//In your TextView

TextView address=(TextView)findViewById(R.id.address); 

address.setTypeface(typeface);

To convert latitude & longitude of location to Address using the method called Reverse Geo-coding.

using getFromLocation(latitude lat, longitude lng, intmaxlength x);
Below coding is used for getting address.

    Geocoder geoCoder = new Geocoder(
        getBaseContext(), Locale.getDefault());
    try {
      List

addresses = geoCoder.getFromLocation(lat,lng,1);

      if (addresses.size() > 0 && addresses != null) {
          StringBuilder result = new StringBuilder();
          myLoc.setText("Now i'm in " +addresses.get(0).getFeatureName()+"-"+addresses.get(0).getLocality()+"-"+addresses.get(0).getAdminArea()+"-"+addresses.get(0).getCountryName() + " at " + dt);

     }
     }
    catch (IOException e) {       
      e.printStackTrace();
    } 

use this code for finding current location.


curlocation.java:
package com.collabera.labs.sai.maps;








public class curlocation extends MapActivity implements LocationListener {
    /** Called when the activity is first created. */
   
    TextView myLoc = null;
   
    MapView    myMapView = null;
   
    MapController myMC = null;
   
    GeoPoint geoPoint = null;
   
    double latitude=13.058587, longitude=80.216717;
   
    Calendar c = Calendar.getInstance(); 
   
    SimpleDateFormat df3 = new SimpleDateFormat("dd-MM-yyyy hh:mm:ss a"); 
    String dt = df3.format(c.getTime());
  
   
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
       
        // Creating TextBox displaying Latitude, Longitude
        myLoc = (TextView) findViewById(R.id.id1);
        String currentLocation = "I'm in: Lat: " + latitude + " Lng: " + longitude + "time:" + dt;
        myLoc.setText(currentLocation);
       
       
        // Creating and initializing Map
        myMapView = (MapView) findViewById(R.id.myGMap);
        geoPoint = new GeoPoint((int) (latitude * 1000000), (int) (longitude * 1000000));
        myMapView.setSatellite(false);
       
        //Getting the MapController to fine tune settings
        myMC = myMapView.getController();
        myMC.setCenter(geoPoint);
        myMC.setZoom(16);
       
        // Add a location mark
        MyLocationOverlay myLocationOverlay = new MyLocationOverlay();
        List list = myMapView.getOverlays();
        list.add(myLocationOverlay);
       
        // Adding zoom controls to Map
        myMapView.setBuiltInZoomControls(true);
        myMapView.displayZoomControls(true);
               
        // Getting locationManager and reflecting changes over map if distance travel by
        // user is greater than 500m from current location.
        LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000L, 500.0f, this);
    }
   
   
From this coding u get current location of Latitude and Longitude. By getting latitude&longitude we can convert it into address using Reverse Geo-coding method.  

Intent:

An intent is a mechanism for describing a specific action, such as “pick a photo” “phone home”.

Types:

There are 2 types of intents that Android understands.

1. Explicit Intent

2. Implicit Intent

In an Explicit intent, you actually specify the activity that is required to respond to the intent. In other words, you explicitly designate the target component. This is typically used for application internal messages.

In an Implicit intent (the main power of the android design), you just declare an intent and leave it to the platform to find an activity that can respond to the intent. Here, you do not declare the target component and hence is typically used for activating components of other applications seamlessly.

Examples:
Implicit intent:  
            String _web=web.getText().toString();
            Uri uri=Uri.parse("http://"+_web);
            Intent i=new Intent(Intent.ACTION_VIEW,uri);
            startActivity(i);

Explicit intent:
                 Intent myIntent1 = new Intent(kpnworld.this, webbwsr.class);
                 kpnworld.this.startActivity(myIntent1);
 

Use ACTION_PICK_WIFI_NETWORK action: startActivity(new Intent(WifiManager.ACTION_PICK_WIFI_NETWORK));

 More details refer:WifiManager

To create MD5 key:
For api key - map Application:
In command prompt

C:\Program Files (x86)\Java\jdk1.6.0_26\bin>keytool.exe -list -alias androiddebugkey -keystore "C:\Users\KPN\.android\debug.keystore" -storepass android -keypass android

       androiddebugkey, 13 Feb, 2012, PrivateKeyEntry,
       Certificate fingerprint (MD5): 22:18:D3:14:F3:40:FB:7B:4F:D8:13:F8:B4:99:2A:59
                                                (or)
C:\Program Files (x86)\Java\jdk1.6.0_26\bin>keytool -list -v -keystore C:\Users\web\.android\debug.keystore

For Windows XP:C:\Documents and Settings\IBM\.android\debug.keystore
Windows Vista/7:C:\Users\KPN\.android\debug.keystore