MainCameraActivity

package epsi.com.phototest;

import android.app.Activity;
import android.content.Context;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.hardware.Camera;
import android.media.MediaScannerConnection;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;
import android.widget.FrameLayout;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;


public class MainCameraActivity extends Activity {
    private Camera mCamera;
    private CameraPreview mPreview;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main_camera);

        // Create an instance of Camera
        mCamera = getCameraInstance();

        // Create our Preview view and set it as the content of our activity.
        mPreview = new CameraPreview(this, mCamera);
        FrameLayout preview = (FrameLayout) findViewById(R.id.mainCameraPreview);
        preview.addView(mPreview);

        Button btn = (Button) findViewById(R.id.mainCameraCapture);
        btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                mCamera.takePicture(null, null, mPicture);
            }
        });
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main_camera, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    private boolean checkCameraHardware(Context context) {
        if (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)) {
            // this device has a camera
            return true;
        } else {
            // no camera on this device
            return false;
        }
    }

    public static Camera getCameraInstance() {
        Camera c = null;
        try {
            c = Camera.open(); // attempt to get a Camera instance
        } catch (Exception e) {
            // Camera is not available (in use or does not exist)
        }
        return c; // returns null if camera is unavailable
    }

    @Override
    protected void onPause() {
        super.onPause();
        //releaseMediaRecorder();       // if you are using MediaRecorder, release it first
        releaseCamera();              // release the camera immediately on pause event
    }

    private void releaseCamera() {
        if (mCamera != null) {
            mCamera.release();        // release the camera for other applications
            mCamera = null;
        }
    }

    public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
        private SurfaceHolder mHolder;
        private Camera mCamera;

        public CameraPreview(Context context, Camera camera) {
            super(context);
            mCamera = camera;

            // Install a SurfaceHolder.Callback so we get notified when the
            // underlying surface is created and destroyed.
            mHolder = getHolder();
            mHolder.addCallback(this);
            // deprecated setting, but required on Android versions prior to 3.0
            mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        }

        public void surfaceCreated(SurfaceHolder holder) {
            // The Surface has been created, now tell the camera where to draw the preview.
            try {
                mCamera.setPreviewDisplay(holder);
                mCamera.startPreview();
            } catch (IOException e) {
                Log.d("Phototest", "Error setting camera preview: " + e.getMessage());
            }
        }

        public void surfaceDestroyed(SurfaceHolder holder) {
            // empty. Take care of releasing the Camera preview in your activity.
        }

        public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
            // If your preview can change or rotate, take care of those events here.
            // Make sure to stop the preview before resizing or reformatting it.

            if (mHolder.getSurface() == null) {
                // preview surface does not exist
                return;
            }

            // stop preview before making changes
            try {
                mCamera.stopPreview();
            } catch (Exception e) {
                // ignore: tried to stop a non-existent preview
            }

            // set preview size and make any resize, rotate or
            // reformatting changes here

            // start preview with new settings
            try {
                mCamera.setPreviewDisplay(mHolder);
                mCamera.startPreview();

            } catch (Exception e) {
                Log.d("PhotoTest", "Error starting camera preview: " + e.getMessage());
            }
        }
    }

    private Camera.PictureCallback mPicture = new Camera.PictureCallback() {

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {

            File pictureFile = getOutputMediaFile(MEDIA_TYPE_IMAGE);
            if (pictureFile == null) {
                Log.d("PhotoTest", "Error creating media file, check storage permissions");
                return;
            }

            try {
                FileOutputStream fos = new FileOutputStream(pictureFile);
                fos.write(data);
                fos.close();
                String filepath = pictureFile.getAbsolutePath();
                Bitmap myBitmap = BitmapFactory.decodeFile(filepath);
                MediaStore.Images.Media.insertImage(getContentResolver(), myBitmap, "PhotoTest", "taken with intent camera");
                MediaScannerConnection.scanFile(MainCameraActivity.this, new String[]{filepath}, null, null);
            } catch (FileNotFoundException e) {
                Log.d("PhotoTest", "File not found: " + e.getMessage());
            } catch (IOException e) {
                Log.d("PhotoTest", "Error accessing file: " + e.getMessage());
            }
        }
    };

    public static final int MEDIA_TYPE_IMAGE = 1;
    public static final int MEDIA_TYPE_VIDEO = 2;

    /**
     * Create a file Uri for saving an image or video
     */
    private static Uri getOutputMediaFileUri(int type) {
        return Uri.fromFile(getOutputMediaFile(type));
    }

    /**
     * Create a File for saving an image or video
     */
    private static File getOutputMediaFile(int type) {
        // To be safe, you should check that the SDCard is mounted
        // using Environment.getExternalStorageState() before doing this.

        File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
                Environment.DIRECTORY_PICTURES), "PhotoTest");
        // This location works best if you want the created images to be shared
        // between applications and persist after your app has been uninstalled.

        // Create the storage directory if it does not exist
        if (!mediaStorageDir.exists()) {
            if (!mediaStorageDir.mkdirs()) {
                Log.d("PhotoTest", "failed to create directory");
                return null;
            }
        }

        // Create a media file name
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        File mediaFile;
        if (type == MEDIA_TYPE_IMAGE) {
            mediaFile = new File(mediaStorageDir.getPath() + File.separator +
                    "IMG_" + timeStamp + ".jpg");
        } else if (type == MEDIA_TYPE_VIDEO) {
            mediaFile = new File(mediaStorageDir.getPath() + File.separator +
                    "VID_" + timeStamp + ".mp4");
        } else {
            return null;
        }

        Log.v("PhotoTest", "storing at " + mediaFile.getAbsolutePath());
        return mediaFile;
    }
}

i tried this code, but after installing it is showing application has stopped. any suggestion?

yes, do not use 6 year old code, it is not maintained