Tomar fotos con la camara y guardar en la sdcard

<uses-permission android:name="android.permission.CAMERA"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <Button
        android:id="@+id/btnTomaFoto"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:text="@string/strTomaFoto" />

</RelativeLayout>

01 package com.bolivia.tomafoto;
02 import java.io.File;
03 import java.io.IOException;
04 import java.text.SimpleDateFormat;
05 import java.util.Date;
06 
07 import android.net.Uri;
08 import android.os.Bundle;
09 import android.os.Environment;
10 import android.provider.MediaStore;
11 import android.annotation.SuppressLint;
12 import android.app.Activity;
13 import android.content.Intent;
14 import android.util.Log;
15 import android.view.Menu;
16 import android.view.View;
17 import android.widget.Button;
18 
19 public class MainActivity extends Activity {
20  
21  private final String ruta_fotos = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES) + "/misfotos/";
22     private File file = new File(ruta_fotos);
23     private Button boton;
24     
25  @Override
26  protected void onCreate(Bundle savedInstanceState) {
27   super.onCreate(savedInstanceState);
28   setContentView(R.layout.activity_main);
29   //======== codigo nuevo ========
30   boton = (Button) findViewById(R.id.btnTomaFoto);
31   //Si no existe crea la carpeta donde se guardaran las fotos
32   file.mkdirs();
33   //accion para el boton
34   boton.setOnClickListener(new View.OnClickListener() {
35 
36    @Override
37    public void onClick(View v) {
38     String file = ruta_fotos + getCode() + ".jpg";
39     File mi_foto = new File( file );
40     try {
41                  mi_foto.createNewFile();
42              } catch (IOException ex) {              
43               Log.e("ERROR ", "Error:" + ex);
44              }       
45              //
46              Uri uri = Uri.fromFile( mi_foto );
47              //Abre la camara para tomar la foto
48              Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
49              //Guarda imagen
50              cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
51              //Retorna a la actividad
52              startActivityForResult(cameraIntent, 0);
53    }
54 
55   });
56   //====== codigo nuevo:end ====== 
57  }
58 
59  /**
60  * Metodo privado que genera un codigo unico segun la hora y fecha del sistema
61  * @return photoCode 
62  * */
63  @SuppressLint("SimpleDateFormat")
64  private String getCode()
65  {
66   SimpleDateFormat dateFormat = new SimpleDateFormat("yyyymmddhhmmss");
67   String date = dateFormat.format(new Date() );
68   String photoCode = "pic_" + date;  
69   return photoCode;
70  }
71  
72  @Override
73  public boolean onCreateOptionsMenu(Menu menu) {
74   // Inflate the menu; this adds items to the action bar if it is present.
75   getMenuInflater().inflate(R.menu.main, menu);
76   return true;
77  }
78 
79 }