custom camera android example

gistfile1.txt

MainActivity.java:

package com.alex.customcamera;

import androidx.appcompat.app.AppCompatActivity;

import android.Manifest;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.pm.ActivityInfo;
import android.hardware.Camera;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.FrameLayout;
import android.widget.Toast;

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

import com.karumi.dexter.Dexter;
import com.karumi.dexter.MultiplePermissionsReport;
import com.karumi.dexter.PermissionToken;
import com.karumi.dexter.listener.PermissionRequest;
import com.karumi.dexter.listener.multi.MultiplePermissionsListener;

public class MainActivity extends AppCompatActivity {

    public static Activity activity;
    Camera camera;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        activity = this;

        Dexter.withActivity(this)
                .withPermissions(Manifest.permission.WRITE_EXTERNAL_STORAGE,
                        Manifest.permission.CAMERA)
                .withListener(new MultiplePermissionsListener() {
                    @Override
                    public void onPermissionsChecked(MultiplePermissionsReport report) {
                        Toast.makeText(MainActivity.this, "Permissions granted", Toast.LENGTH_SHORT).show();
                    }

                    @Override
                    public void onPermissionRationaleShouldBeShown(List<PermissionRequest> permissions, PermissionToken token) {

                    }
                }).check();

        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);

        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED);

        camera = getCameraInstance();
        CameraPreview mCameraPreview = new CameraPreview(this, camera);

        FrameLayout preview = findViewById(R.id.camera_preview);
        preview.addView(mCameraPreview);

        Button captureButton = findViewById(R.id.button_capture);
        captureButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                camera.takePicture(null, null, picture);
            }
        });
    }

    private Camera getCameraInstance() {
        Camera camera = null;
        try {
            camera = Camera.open();
        } catch (Exception e) {
            Toast.makeText(MainActivity.activity, "getCameraInstance error", Toast.LENGTH_SHORT).show();
        }
        return camera;
    }

    Camera.PictureCallback picture = new Camera.PictureCallback() {
        @Override
        public void onPictureTaken(byte[] data, Camera camera) {
            File f = getOutputMediaFile();
            if (f == null) {
                return;
            }
            try {
                FileOutputStream fos = new FileOutputStream(f);
                fos.write(data);
                fos.close();

                // OPEN NEW PHOTO FILE
                Uri uri = Uri.fromFile(f);
                Intent intent = new Intent(Intent.ACTION_VIEW);
                intent.setDataAndType(uri, "image/jpeg");
                intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                activity.startActivity(intent);

                activity.finish();
                System.exit(0);

            } catch (IOException e) {
                Toast.makeText(MainActivity.activity, "onPictureTaken error", Toast.LENGTH_SHORT).show();
            }
        }
    };

    File getOutputMediaFile() {
        File directory = new File(
                Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES), "MyCameraApp");
        if (!directory.exists()) {
            if (!directory.mkdirs()) {
                Toast.makeText(this, "failed to create directory", Toast.LENGTH_SHORT).show();
                return null;
            }
        }

        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());

        File f;
        f = new File(directory.getPath() + File.separator + "IMG_" + timeStamp + ".jpg");

        return f;
    }
}

class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {

    private Camera cam;

    public CameraPreview(Context context, Camera camera) {
        super(context);
        cam = camera;
        SurfaceHolder holder = this.getHolder();
        holder.addCallback(this);
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        try {
            cam.setPreviewDisplay(holder);
            cam.setDisplayOrientation(90);
            cam.startPreview();
        } catch (IOException e) {
            Toast.makeText(MainActivity.activity, "surfaceCreated error", Toast.LENGTH_SHORT).show();
        }
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        cam.stopPreview();
        cam.release();
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
        try {
            cam.setPreviewDisplay(holder);
            cam.startPreview();

        } catch (Exception e) {
            Toast.makeText(MainActivity.activity, "surfaceChanged error", Toast.LENGTH_SHORT).show();
        }
    }
}

==============================================================================================================================

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <FrameLayout
        android:id="@+id/camera_preview"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1" />

    <Button
        android:id="@+id/button_capture"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Сделать снимок" />

</LinearLayout>

==============================================================================================================================

styles.xml: (optionally)

<resources>
    <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>
    </style>
</resources>

==============================================================================================================================

AndroidManifest.xml:

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