Camera Preview to render camera capture in real time + take photo + resize it + upload it to the server

activity_take_photo.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@color/orders_grey_background">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
        app:elevation="16dp">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar_actionbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:layout_scrollFlags="scroll|enterAlways"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />

    </android.support.design.widget.AppBarLayout>

    <!-- Camera -->
    <FrameLayout
        android:id="@+id/camera_preview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_marginBottom="64dp"
        android:layout_marginTop="@dimen/abc_action_bar_default_height_material" />

    <!-- Receipt photo -->
    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="top|center_horizontal"
        android:layout_marginTop="80dp"
        android:background="@drawable/receipt_photo_background"
        android:orientation="vertical">

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_horizontal"
            android:text="@string/receipt_photo"
            android:textColor="@color/c_white"
            android:textSize="15sp"/>

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_horizontal"
            android:text="@string/refine_focus"
            android:textColor="@color/c_white"
            android:textSize="14sp" />

    </LinearLayout>

    <!-- Take photo button -->
    <FrameLayout
        android:id="@+id/take_photo_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="@drawable/take_photo_background"
        android:layout_gravity="bottom|center_horizontal"
        android:layout_marginBottom="90dp">

        <ImageView
            android:layout_width="40dp"
            android:layout_height="40dp"
            android:src="@drawable/ic_camera_alt_black_48dp"
            android:layout_gravity="center"/>

    </FrameLayout>

    <!-- Retake photo -->
    <TextView
        android:id="@+id/retake_photo_button"
        android:layout_width="match_parent"
        android:layout_height="48dp"
        android:layout_gravity="bottom|center_horizontal"
        android:layout_marginBottom="64dp"
        android:background="@drawable/retake_photo_background"
        android:gravity="center"
        android:text="@string/retake_photo"
        android:textAllCaps="true"
        android:textColor="@color/c_white"
        android:textSize="16sp"
        android:textStyle="bold"
        android:visibility="gone"/>


    <!-- Step 1 of 4      Continue -->
    <RelativeLayout
        android:id="@+id/step_one_of_four_layout"
        android:layout_width="match_parent"
        android:layout_height="64dp"
        android:layout_gravity="bottom"
        android:background="@color/footer_white_background"
        android:orientation="vertical">

        <View
            android:layout_width="match_parent"
            android:layout_height="1dp"
            android:layout_alignParentTop="true"
            android:background="@color/orders_grey_line" />

        <ImageView
            android:id="@+id/next_arrow"
            android:layout_width="32dp"
            android:layout_height="32dp"
            android:layout_alignParentRight="true"
            android:layout_centerVertical="true"
            android:scaleType="fitXY"
            android:src="@drawable/ic_keyboard_arrow_right_white_48dp"
            android:tint="@color/accepted_right_arrow" />

        <TextView
            android:id="@+id/next_text"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerVertical="true"
            android:layout_toLeftOf="@+id/next_arrow"
            android:fontFamily="sans-serif"
            android:text="@string/next"
            android:textAllCaps="true"
            android:textColor="@color/accepted_right_arrow"
            android:textSize="16sp"
            android:textStyle="bold" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_centerVertical="true"
            android:layout_toLeftOf="@+id/next_text"
            android:fontFamily="sans-serif"
            android:paddingLeft="@dimen/general_view_margin"
            android:text="@string/step_1_of_4"
            android:textColor="@color/step_x_of_y"
            android:textSize="18sp"
            android:textStyle="normal" />

    </RelativeLayout>

</android.support.design.widget.CoordinatorLayout>

CameraPreview.java

import android.content.Context;
import android.hardware.Camera;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

import java.io.IOException;
import java.util.List;

public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {

    private final String TAG = "CameraPreview";

    private SurfaceHolder holder;
    private Camera camera;
    private List<Camera.Size> supportedPreviewSizes;
    private Camera.Size previewSize;

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

        // supported preview sizes
        supportedPreviewSizes = camera.getParameters().getSupportedPreviewSizes();

        // Install a SurfaceHolder.Callback so we get notified when the
        // underlying surface is created and destroyed.
        holder = getHolder();
        holder.addCallback(this);

        // deprecated setting, but required on Android versions prior to 3.0
        holder.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 {

            Camera.Parameters params = camera.getParameters();
            if (params.getSupportedFocusModes().contains(
                    Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO)) {
                params.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO);
            }
            camera.setParameters(params);

            camera.setPreviewDisplay(holder);
            camera.stopPreview();
            camera.setDisplayOrientation(90);
            camera.startPreview();

        } catch (IOException e) {
            Log.d(TAG, "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 (this.holder.getSurface() == null){
            // preview surface does not exist
            return;
        }

        // stop preview before making changes
        try {
            camera.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 {

            Camera.Parameters parameters = camera.getParameters();
            parameters.setPreviewSize(previewSize.width, previewSize.height);
            camera.setParameters(parameters);
            camera.setDisplayOrientation(90);
            camera.setPreviewDisplay(holder);
            camera.startPreview();

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

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
        final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);

        if (supportedPreviewSizes != null) {
            previewSize = getOptimalPreviewSize(supportedPreviewSizes, width, height);
        }

        float ratio;
        if(previewSize.height >= previewSize.width)
            ratio = (float) previewSize.height / (float) previewSize.width;
        else
            ratio = (float) previewSize.width / (float) previewSize.height;

        setMeasuredDimension(width, (int) (width * ratio));
    }

    private Camera.Size getOptimalPreviewSize(List<Camera.Size> sizes, int w, int h) {
        final double ASPECT_TOLERANCE = 0.1;
        double targetRatio = (double) h / w;

        if (sizes == null)
            return null;

        Camera.Size optimalSize = null;
        double minDiff = Double.MAX_VALUE;

        int targetHeight = h;

        for (Camera.Size size : sizes) {
            double ratio = (double) size.height / size.width;
            if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE)
                continue;

            if (Math.abs(size.height - targetHeight) < minDiff) {
                optimalSize = size;
                minDiff = Math.abs(size.height - targetHeight);
            }
        }

        if (optimalSize == null) {
            minDiff = Double.MAX_VALUE;
            for (Camera.Size size : sizes) {
                if (Math.abs(size.height - targetHeight) < minDiff) {
                    optimalSize = size;
                    minDiff = Math.abs(size.height - targetHeight);
                }
            }
        }

        return optimalSize;
    }
}

TakePhotoActivity.java

package com.cornershopapp.shopper.android.ui.main;

import android.app.LoaderManager;
import android.content.ContentUris;
import android.content.CursorLoader;
import android.content.Intent;
import android.content.Loader;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.hardware.Camera;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.view.MenuItem;
import android.view.View;
import android.widget.FrameLayout;
import android.widget.RelativeLayout;
import android.widget.TextView;

import com.cornershopapp.shopper.android.R;
import com.cornershopapp.shopper.android.entity.responses.SimpleResponse;
import com.cornershopapp.shopper.android.enums.BarcodeTypes;
import com.cornershopapp.shopper.android.enums.PendingRequestTypes;
import com.cornershopapp.shopper.android.network.RestApi;
import com.cornershopapp.shopper.android.services.InsertPendingRequestService;
import com.cornershopapp.shopper.android.sql.Order;
import com.cornershopapp.shopper.android.ui.BaseActivity;
import com.cornershopapp.shopper.android.utils.CameraPreview;
import com.cornershopapp.shopper.android.utils.Utils;

import org.parceler.Parcels;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import butterknife.ButterKnife;
import butterknife.InjectView;
import retrofit.Callback;
import retrofit.RetrofitError;
import retrofit.client.Response;

/**
 * Created by romantolmachev on 11/11/15.
 */
public class TakePhotoActivity extends BaseActivity implements View.OnClickListener,
        LoaderManager.LoaderCallbacks<Cursor> {

    @InjectView(R.id.step_one_of_four_layout)
    RelativeLayout stepOneOfFourLayout;

    @InjectView(R.id.camera_preview)
    FrameLayout cameraPreviewLayout;

    @InjectView(R.id.take_photo_button)
    FrameLayout takePhotoButton;

    @InjectView(R.id.retake_photo_button)
    TextView retakePhotoButton;

    Camera camera;
    CameraPreview cameraPreview;
    File photoFile;
    boolean photoTaken;

    Camera.PictureCallback picture = new Camera.PictureCallback() {

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

            photoTaken = true;

            new Thread(new Runnable() {
                @Override
                public void run() {

                    byte[] resizedImageData = resizeImage(originalImageData);
                    photoFile = Utils.createPublicImageFile();
                    if (photoFile == null) {
                        System.out.println("Error creating media file, check storage permissions: ");
                        return;
                    }

                    try {
                        FileOutputStream fos = new FileOutputStream(photoFile);
                        fos.write(resizedImageData);
                        fos.close();

                        //TODO switch to Retrofit 2.0 and cancel uploading previous screenshot
                        uploadPhotoRequest();
                    } catch (FileNotFoundException e) {
                        System.out.println("File not found: " + e.getMessage());
                    } catch (IOException e) {
                        System.out.println("Error accessing file: " + e.getMessage());
                    }

                }
            }).start();

        }
    };

    final int PHOTO_WIDTH = 1200;
    final int PHOTO_HEIGHT = 1200;

    BarcodeTypes barcodeType;
    float total;

    public static final int CHECKOUT = 102;

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (resultCode == RESULT_OK && requestCode == CHECKOUT) {

            setResult(RESULT_OK);
            finish();
        }

    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_take_photo);
        setUpToolbarAndTitleAndHome(getString(R.string.finish_picking), R.menu.menu_accept_order);
        ButterKnife.inject(this);

        stepOneOfFourLayout.setOnClickListener(this);
        takePhotoButton.setOnClickListener(this);
        retakePhotoButton.setOnClickListener(this);

        getLoaderManager().initLoader(1, null, this);
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()) {
            case R.id.step_one_of_four_layout:

                if(photoTaken) {

                    Bundle args = new Bundle();
                    args.putParcelable(getString(R.string.key_barcode), Parcels.wrap(barcodeType));
                    args.putFloat(getString(R.string.key_order_total), total);

                    startActivityForResult(new Intent(this, ScanReceiptBarcodeActivity.class).putExtras(args), CHECKOUT);
                }

                break;
            case R.id.take_photo_button:
                camera.takePicture(null, null, picture);
                takePhotoButton.setVisibility(View.GONE);
                retakePhotoButton.setVisibility(View.VISIBLE);
                break;
            case R.id.retake_photo_button:
                retakePhotoButton.setVisibility(View.GONE);
                takePhotoButton.setVisibility(View.VISIBLE);
                camera.startPreview();
                break;
        }
    }

    @Override
    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
        switch (item.getItemId()) {
            case R.id.menu_call:
                showWhomToCallDialog();
                return true;
        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    protected void onResume() {
        super.onResume();

        camera = getCameraInstance();
        if(camera != null) {
            setupCamera();
        } else {

            /**
             * Delay is necessary for cases when you go back from the ScanReceiptBarcodeActivity
             * and need to wait a bit before Camera is released
             */
            cameraPreviewLayout.postDelayed(new Runnable() {
                @Override
                public void run() {
                    camera = getCameraInstance();
                    if(camera != null) {
                        setupCamera();
                    }
                }
            }, 300);

        }

    }

    @Override
    protected void onPause() {
        super.onPause();
        if (camera != null) {
            camera.setPreviewCallback(null);
            cameraPreview.getHolder().removeCallback(cameraPreview);
            camera.release();
            camera = null;
        }
    }

    /**
     * A safe way to get an instance of the Camera object.
     */
    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
    }

    byte[] resizeImage(byte[] input) {
        Bitmap original = BitmapFactory.decodeByteArray(input, 0, input.length);
        Bitmap resized = Bitmap.createScaledBitmap(original, PHOTO_WIDTH, PHOTO_HEIGHT, true);

        ByteArrayOutputStream blob = new ByteArrayOutputStream();
        resized.compress(Bitmap.CompressFormat.JPEG, 100, blob);

        return blob.toByteArray();
    }

    void setupCamera() {
        cameraPreview = new CameraPreview(TakePhotoActivity.this, camera);
        cameraPreviewLayout.removeAllViews();
        cameraPreviewLayout.addView(cameraPreview);
        retakePhotoButton.setVisibility(View.GONE);
        takePhotoButton.setVisibility(View.VISIBLE);
    }

    @Override
    public Loader<Cursor> onCreateLoader(int i, Bundle bundle) {
        String[] projection = {Order._ID, Order.TOTAL, Order.SCAN_TYPE};
        return new CursorLoader(this, ContentUris.withAppendedId(Order.CONTENT_URI, orderId), projection, null, null, null);
    }

    @Override
    public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {
        if (cursor != null && cursor.moveToFirst()) {
            //if scan receipt is enabled
            if (cursor.getString(cursor.getColumnIndex(Order.SCAN_TYPE)) != null) {
                barcodeType = BarcodeTypes.valueOf(cursor.getString(cursor.getColumnIndex(Order.SCAN_TYPE)));
                total = cursor.getFloat(cursor.getColumnIndex(Order.TOTAL));
            }
        }
    }

    @Override
    public void onLoaderReset(Loader<Cursor> loader) {

    }

    /**
     * ================================= API REQUESTS ==============================================
     */

    private void uploadPhotoRequest() {

            RestApi.uploadReceipt(orderId, photoFile, new Callback<SimpleResponse>() {
                @Override
                public void success(SimpleResponse simpleResponse, Response response) {

                }

                @Override
                public void failure(RetrofitError error) {
                    handleErrors(error);
                }
            });
        
    }

}