Android Checking Front & Back Camera and Take a photo automatically without user interaction

The Android framework includes support for various cameras and camera features available on devices, allowing you to capture pictures and videos in your applications. This document discusses a quick, simple approach to image and video capture and outlines an advanced approach for creating custom camera experiences for your users.

Code:

1. MainActivity.java
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.hardware.Camera;
import android.os.Bundle;
import android.os.CountDownTimer;
import android.os.Environment;
import android.view.SurfaceView;
import android.widget.TextView;

public class MainActivity extends Activity{
private Camera camera; // camera object
private TextView TimeLeft; // time left field
File mediaFile;
private static final String IMAGE_DIRECTORY_NAME = "Captured_Images";
int numberOfCameras;
private TextView cameras;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TimeLeft=(TextView)findViewById(R.id.TimeLeft); // make time left object
camera = Camera.open();
 numberOfCameras = Camera.getNumberOfCameras();
cameras=(TextView)findViewById(R.id.camera);
 if(numberOfCameras==0)
cameras.setText("Camera Not Supported in this Mobile");
else if(numberOfCameras==2)
 cameras.setText("No Of Cameras:"+numberOfCameras+"\n Both Front & Back Camera Available");
else
cameras.setText("No Of Cameras:"+numberOfCameras+"\n Back Camera only Available");
SurfaceView view = new SurfaceView(this);
try {
camera.setPreviewDisplay(view.getHolder()); // feed dummy surface to surface
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
new CountDownTimer(10000,1000){
@Override
public void onFinish() {
// count finished
TimeLeft.setText("Picture Taken");
camera.takePicture(null, null, null, jpegCallBack);
}
 @Override
public void onTick(long millisUntilFinished) {
// every time 1 second passes
TimeLeft.setText("Seconds Left: "+millisUntilFinished/1000);
}
 }.start();
camera.startPreview();   
}
 Camera.PictureCallback jpegCallBack=new Camera.PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) {
File mediaStorageDir = new File(Environment.getExternalStorageDirectory(),IMAGE_DIRECTORY_NAME);
// Create the storage directory if it does not exist
  if (!mediaStorageDir.exists()) {
 if (!mediaStorageDir.mkdirs()) {
             }
}
 String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss",Locale.getDefault()).format(new Date());
mediaFile = new File(mediaStorageDir.getPath() + File.separator+ "IMG_" + timeStamp + ".png");
try {
Bitmap userImage = BitmapFactory.decodeByteArray(data, 0, data.length);
// set file out stream
FileOutputStream out = new FileOutputStream(mediaFile);
// set compress format quality and stream
userImage.compress(Bitmap.CompressFormat.JPEG, 90, out);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
};
}

2. Update Android Manifest File:
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

3. activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:gravity="center">
    <TextView
android:id="@+id/camera"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text=""
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#7ba400"/>

<TextView
android:id="@+id/TimeLeft"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text=""
android:textColor="#29166f"
android:textAppearance="?android:attr/textAppearanceMedium"/>

</LinearLayout>

Output:
Photo has been taken automatically and stored in  Captured_Images folder in SD Card.