Spinner example using AppCompatSpinner widget

          When we have a requirement to use spinner(drop down) to show list of objects in your application. Here we will see how to use AppCompatSpinner widget in this tutorial. Also we will see how to pass list of objects and getting selected object.

Screen Shot:

Download Source Code:

Step 1:   "activity_main.xml"

   Open activity_main.xml and add AppCompatSpinner view with TextView like below.

<?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:background="#FFF2A9"
    android:orientation="vertical">


    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="10dp"
        android:orientation="vertical">

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:text="Select Company"
            android:textColor="@color/colorPrimary" />


        <android.support.v7.widget.AppCompatSpinner
            android:id="@+id/sp_companies"
            android:layout_width="match_parent"
            android:layout_height="40dp"
            android:layout_marginTop="5dp"
            android:background="@drawable/bg_dropdown" />
    </LinearLayout>


</LinearLayout>

Step 2:  "bg_dropdown.xml"

 For adding background create css xml file in your drawable folder. the code like below.

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>


        <layer-list>
            <item>
                <shape>
                    <stroke
                        android:width="1dip"
                        android:color="@color/black_text" />

                    <corners android:radius="3dp" />

                    <solid android:color="@android:color/transparent"></solid>


                    <padding
                        android:bottom="5.0dip"
                        android:left="5.0dip"
                        android:right="5.0dip"
                        android:top="5.0dip" />
                </shape>
            </item>


            <item>
                <bitmap
                    android:gravity="center_vertical|right"
                    android:src="@drawable/ic_keyboard_arrow_down_black_24dp" />

            </item>


        </layer-list>


    </item>
</layer-list>

Step 3:  "CompanyModel.java"

           Create Company Model class to pass objects in ArrayList. I am taking Id, name, and location parameters. then generated setters and getters with toString() method. toString() will use in spinner to show name parameter. you can get complete class from below.

package com.prasad.customspinnerex;

import java.io.Serializable;


public class CompanyModel implements Serializable {
    private String CompanyId;
    private String CompanyName;
    private String Location;

    public CompanyModel(String companyId, String companyName, String location) {
        CompanyId = companyId;
        CompanyName = companyName;
        Location = location;
    }

    public String getCompanyId() {
        return CompanyId;
    }

    public void setCompanyId(String companyId) {
        CompanyId = companyId;
    }

    public String getCompanyName() {
        return CompanyName;
    }

    public void setCompanyName(String companyName) {
        CompanyName = companyName;
    }

    public String getLocation() {
        return Location;
    }

    public void setLocation(String location) {
        Location = location;
    }

    @Override
    public String toString() {

        return CompanyName;
    }
}

Step 4: "MainActivity.java"

          Open MainActivity class and we declare Spinner view and ArrayList. Then we will added List of objects to ArrayList. Now list will pass to Adapter. you can get complete class from below.

package com.prasad.customspinnerex;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.AppCompatSpinner;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    private AppCompatSpinner sp_companies;
    private List<CompanyModel> companies_list;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        sp_companies = (AppCompatSpinner) findViewById(R.id.sp_companies);
        companies_list = new ArrayList<>();

        companies_list.add(new CompanyModel("Id1", "Android", "Hyderabad"));
        companies_list.add(new CompanyModel("Id2", "Apple", "Banglore"));
        companies_list.add(new CompanyModel("Id3", "TCS", "Chennai"));
        companies_list.add(new CompanyModel("Id4", "IBM", "Mumbai"));
        companies_list.add(new CompanyModel("Id5", "Google", "Banglore"));

        ArrayAdapter adapter = new ArrayAdapter<>(this, android.R.layout.simple_spinner_item, companies_list);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        sp_companies.setAdapter(adapter);
        sp_companies.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {

                String companyId = companies_list.get(i).getCompanyId();
                String companyName = companies_list.get(i).getCompanyName();
                Toast.makeText(MainActivity.this, "Company Name: " + companyName, Toast.LENGTH_SHORT).show();

            }

            @Override
            public void onNothingSelected(AdapterView<?> adapterView) {

            }
        });


    }
}

Step 5: "colors.xml"

       Open colors.xml file from values folder under res. add the below text colors.

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="colorPrimary">#3F51B5</color>
    <color name="colorPrimaryDark">#303F9F</color>
    <color name="colorAccent">#FF4081</color>
    <color name="hint_text">#919191</color>
    <color name="black_text">#000000</color>
</resources>

Simple Barcode and QR code scanner using Zxing or Zbar libraries

         When a requirement in your app to scan bar codes and QR codes, in this tutorial we will see how to scanning bar codes and QR codes. Here I am using Zxing and Zbar open source libraries. you can choose any one of the library.

Screen Shots:

Download Source Code

Step 1:  Build Gradle
              To start this application we need to include Zxing and Zbar dependencies in our build.gradle file.Check the below my build.gradle file.

build.gradle:

apply plugin: 'com.android.application'

android {
    compileSdkVersion 25
    buildToolsVersion "25.0.2"
    defaultConfig {
        applicationId "com.prasad.zxingscannerex"
        minSdkVersion 15
        targetSdkVersion 25
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.android.support:appcompat-v7:25.1.0'
    compile 'com.android.support.constraint:constraint-layout:1.0.0-beta4'
    testCompile 'junit:junit:4.12'

    compile 'me.dm7.barcodescanner:zxing:1.9'
    compile 'me.dm7.barcodescanner:zbar:1.9'


}

Step 2: XML Layouts
             Open activity_main.xml file and do the below changes.

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#ffffff">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:layout_margin="10dp"
        android:orientation="vertical">

        <Button
            android:id="@+id/btn_scanner"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Zxing Scanner"
            android:textAllCaps="false" />

        <Button
            android:id="@+id/btn_zbar_scanner"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="20dp"
            android:text="Zbar Scanner"
            android:textAllCaps="false" />

    </LinearLayout>


</RelativeLayout>

Create a new layout resource name as activity_zxing_scanner.xml and modify below changes.

activity_zxing_scanner.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#ffffff">


    <FrameLayout
        android:id="@+id/content_frame"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</RelativeLayout>

Create a new layout resource name as activity_zbar_scanner.xml and modify below changes.

activity_zbar_scanner.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#ffffff">
    <FrameLayout
        android:id="@+id/content_frame"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</RelativeLayout>

Step 3: Java Classes
             Open MainActivity.java class and do the below changes.

MainActivity.java:

package com.prasad.zxingscannerex;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {


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

        Button scannerBtn = (Button) findViewById(R.id.btn_scanner);
        Button zbarScannerBtn = (Button) findViewById(R.id.btn_zbar_scanner);

        scannerBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Intent intent = new Intent(v.getContext(), ZxingScannerActivity.class);
                startActivity(intent);
            }
        });

        zbarScannerBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Intent intent = new Intent(v.getContext(), ZbarScannerActivity.class);
                startActivity(intent);
            }
        });
    }
}

   Create a new Activity java class name as ZxingScannerActivity.java and modify below changes.

ZxingScannerActivity.java:

package com.prasad.zxingscannerex;

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.view.ViewGroup;
import android.widget.Toast;

import com.google.zxing.Result;

import me.dm7.barcodescanner.zxing.ZXingScannerView;

public class ZxingScannerActivity extends AppCompatActivity implements ZXingScannerView.ResultHandler {

    private ZXingScannerView mScannerView;
    static final Integer CAMERA = 0x1;

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

        ViewGroup contentFrame = (ViewGroup) findViewById(R.id.content_frame);
        mScannerView = new ZXingScannerView(this);
        contentFrame.addView(mScannerView);
        askForPermission(Manifest.permission.CAMERA, CAMERA);
    }

    private void askForPermission(String permission, Integer requestCode) {

        if (ContextCompat.checkSelfPermission(ZxingScannerActivity.this, permission) != PackageManager.PERMISSION_GRANTED) {

            // Should we show an explanation?
            if (ActivityCompat.shouldShowRequestPermissionRationale(ZxingScannerActivity.this, permission)) {

                //This is called if user has denied the permission before
                //In this case I am just asking the permission again
                ActivityCompat.requestPermissions(ZxingScannerActivity.this, new String[]{permission}, requestCode);

            } else {

                ActivityCompat.requestPermissions(ZxingScannerActivity.this, new String[]{permission}, requestCode);
            }
        } else {

            // Toast.makeText(this, "" + permission + " is already granted.", Toast.LENGTH_SHORT).show();
            mScannerView.setResultHandler(this);
            mScannerView.startCamera();
        }
    }


    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (ActivityCompat.checkSelfPermission(this, permissions[0]) == PackageManager.PERMISSION_GRANTED) {
            switch (requestCode) {
                //Camera
                case 1:
                    mScannerView.setResultHandler(this);
                    mScannerView.startCamera();
                    break;


            }

            Toast.makeText(this, "Permission granted", Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(this, "Permission denied", Toast.LENGTH_SHORT).show();
        }

    }


    @Override
    public void onPause() {
        super.onPause();
        mScannerView.stopCamera();
    }

    @Override
    public void handleResult(Result result) {

        Toast.makeText(this, "Contents = " + result.getText() +
                ", Format = " + result.getBarcodeFormat().toString(), Toast.LENGTH_SHORT).show();

        // * Wait 3 seconds to resume the preview.
        Handler handler = new Handler();
        handler.postDelayed(new Runnable() {
            @Override
            public void run() {
                mScannerView.resumeCameraPreview(ZxingScannerActivity.this);
            }
        }, 3000);

    }
}

  Create a new Activity java class name as ZbarScannerActivity.java and modify below changes.

ZbarScannerActivity.java:

package com.prasad.zxingscannerex;

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.view.ViewGroup;
import android.widget.Toast;

import me.dm7.barcodescanner.zbar.Result;
import me.dm7.barcodescanner.zbar.ZBarScannerView;


public class ZbarScannerActivity extends AppCompatActivity implements ZBarScannerView.ResultHandler {

    private ZBarScannerView mScannerView;
    static final Integer CAMERA = 0x1;

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

        ViewGroup contentFrame = (ViewGroup) findViewById(R.id.content_frame);
        mScannerView = new ZBarScannerView(this);
        contentFrame.addView(mScannerView);
        askForPermission(Manifest.permission.CAMERA, CAMERA);

    }

    private void askForPermission(String permission, Integer requestCode) {

        if (ContextCompat.checkSelfPermission(ZbarScannerActivity.this, permission) != PackageManager.PERMISSION_GRANTED) {

            // Should we show an explanation?
            if (ActivityCompat.shouldShowRequestPermissionRationale(ZbarScannerActivity.this, permission)) {

                //This is called if user has denied the permission before
                //In this case I am just asking the permission again
                ActivityCompat.requestPermissions(ZbarScannerActivity.this, new String[]{permission}, requestCode);

            } else {

                ActivityCompat.requestPermissions(ZbarScannerActivity.this, new String[]{permission}, requestCode);
            }
        } else {

            // Toast.makeText(this, "" + permission + " is already granted.", Toast.LENGTH_SHORT).show();
            mScannerView.setResultHandler(this);
            mScannerView.startCamera();
        }
    }


    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (ActivityCompat.checkSelfPermission(this, permissions[0]) == PackageManager.PERMISSION_GRANTED) {
            switch (requestCode) {
                //Camera
                case 1:
                    mScannerView.setResultHandler(this);
                    mScannerView.startCamera();
                    break;


            }

            Toast.makeText(this, "Permission granted", Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(this, "Permission denied", Toast.LENGTH_SHORT).show();
        }

    }


    @Override
    public void onPause() {
        super.onPause();
        mScannerView.stopCamera();
    }

    @Override
    public void handleResult(Result result) {

        Toast.makeText(this, "Contents = " + result.getContents() +
                ", Format = " + result.getBarcodeFormat().getName(), Toast.LENGTH_SHORT).show();
        
        // * Wait 3 seconds to resume the preview.       
        Handler handler = new Handler();
        handler.postDelayed(new Runnable() {
            @Override
            public void run() {
                mScannerView.resumeCameraPreview(ZbarScannerActivity.this);
            }
        }, 3000);
    }
}

4. Android Manifest
    Open AndroidManifest.xml add the Camera permission and declare activity classes.

    AndroidManifest.xml:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.prasad.zxingscannerex">

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

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".ZxingScannerActivity" />
        <activity android:name=".ZbarScannerActivity"></activity>
    </application>

</manifest>

5. Reference:
     Credits goes to this GitHub link.
    






       

Pick image from gallery or camera using runtime permission

                  When a requirement in your app, you want to pick image from gallery or image using run time permission. In this tutorial we can see how to pick image from gallery or camera.

Screen Shots:

Download Source Code


Step 1: XML Layout
       Open activity_main.xml file from layout folder, add Image View  and Button widgets like below.

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<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"
    tools:context="com.prasad.imagepickerex.MainActivity">

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_above="@+id/imagePickBtn"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:layout_margin="20dp"
        android:background="#E8E8E8" />

    <Button
        android:id="@+id/imagePickBtn"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_margin="20dp"
        android:background="@color/colorPrimary"
        android:text="Pick Image"
        android:textColor="#ffffff"
        android:textSize="18dp" />

</RelativeLayout>

Step 2: Java Classes
       Open MainActivity.java class do the changes like below.

MainActivity.java:

package com.prasad.imagepickerex;

import android.content.Intent;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

import java.io.File;

public class MainActivity extends AppCompatActivity implements ImageUtils.ImageAttachmentListener {

    ImageView imageView;
    Button imagePickBtn;

    private Bitmap bitmap;
    private String file_name;

    ImageUtils imageutils;

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

        imageutils = new ImageUtils(this);

        imageView = (ImageView) findViewById(R.id.imageView);
        imagePickBtn = (Button) findViewById(R.id.imagePickBtn);

        imagePickBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                imageutils.imagepicker(1);
            }
        });
    }

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

    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        imageutils.request_permission_result(requestCode, permissions, grantResults);
    }

    @Override
    public void image_attachment(int from, String filename, Bitmap file, Uri uri) {

        bitmap = file;
        file_name = filename;
        imageView.setImageBitmap(file);

        String path = Environment.getExternalStorageDirectory() + File.separator + "ImagePicker" + File.separator;
        imageutils.createImage(file, filename, path, false);

    }
}

Create a new class with name as ImageUtils.java, copy the below code.

ImageUtils.java:

package com.prasad.imagepickerex;

import android.Manifest;
import android.app.Activity;
import android.content.ContentValues;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.media.ExifInterface;
import android.net.Uri;
import android.os.Build;
import android.provider.MediaStore;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AlertDialog;
import android.util.Base64;
import android.util.Log;
import android.widget.Toast;

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

/**
 * Created by venkataprasad.kukka on 01-03-2017.
 */

public class ImageUtils {

    Context context;
    Activity current_activity;

    ImageAttachmentListener imageAttachment_callBack;

    String selected_path = "";
    Uri imageUri;
    File path = null;

    int from = 0;

    public ImageUtils(Activity act) {

        this.context = act;
        this.current_activity = act;
        imageAttachment_callBack = (ImageAttachmentListener) context;
    }

    /**
     * Get file name from path
     *
     * @param path
     * @return
     */

    public String getfilename_from_path(String path) {
        return path.substring(path.lastIndexOf('/') + 1, path.length());

    }

    /**
     * Get Image URI from Bitmap
     *
     * @param context
     * @param photo
     * @return
     */

    public Uri getImageUri(Context context, Bitmap photo) {
        ByteArrayOutputStream bytes = new ByteArrayOutputStream();
        photo.compress(Bitmap.CompressFormat.PNG, 80, bytes);
        String path = MediaStore.Images.Media.insertImage(context.getContentResolver(), photo, "Title", null);
        return Uri.parse(path);
    }

    /**
     * Get Path from Image URI
     *
     * @param uri
     * @return
     */

    public String getPath(Uri uri) {
        String[] projection = {MediaStore.Images.Media.DATA};
        Cursor cursor = this.context.getContentResolver().query(uri, projection, null, null, null);
        int column_index = 0;
        if (cursor != null) {
            column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
            cursor.moveToFirst();
            String path = cursor.getString(column_index);
            cursor.close();
            return path;
        } else
            return uri.getPath();
    }

    /**
     * Bitmap from String
     *
     * @param encodedString
     * @return
     */
    public Bitmap StringToBitMap(String encodedString) {
        try {
            byte[] encodeByte = Base64.decode(encodedString, Base64.DEFAULT);
            Bitmap bitmap = BitmapFactory.decodeByteArray(encodeByte, 0, encodeByte.length);
            return bitmap;
        } catch (Exception e) {
            e.getMessage();
            return null;
        }
    }


    /**
     * Get String from Bitmap
     *
     * @param bitmap
     * @return
     */

    public String BitMapToString(Bitmap bitmap) {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        bitmap.compress(Bitmap.CompressFormat.PNG, 80, baos);
        byte[] b = baos.toByteArray();
        String temp = Base64.encodeToString(b, Base64.DEFAULT);
        return temp;
    }


    /**
     * Check Camera Availability
     *
     * @return
     */

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


    /**
     * Compress Imgae
     *
     * @param imageUri
     * @param height
     * @param width
     * @return
     */


    public Bitmap compressImage(String imageUri, float height, float width) {

        String filePath = getRealPathFromURI(imageUri);
        Bitmap scaledBitmap = null;

        BitmapFactory.Options options = new BitmapFactory.Options();

        // by setting this field as true, the actual bitmap pixels are not loaded in the memory. Just the bounds are loaded. If
        // you try the use the bitmap here, you will get null.

        options.inJustDecodeBounds = true;
        Bitmap bmp = BitmapFactory.decodeFile(filePath, options);

        int actualHeight = options.outHeight;
        int actualWidth = options.outWidth;

        // max Height and width values of the compressed image is taken as 816x612

        float maxHeight = height;
        float maxWidth = width;
        float imgRatio = actualWidth / actualHeight;
        float maxRatio = maxWidth / maxHeight;

        // width and height values are set maintaining the aspect ratio of the image

        if (actualHeight > maxHeight || actualWidth > maxWidth) {
            if (imgRatio < maxRatio) {
                imgRatio = maxHeight / actualHeight;
                actualWidth = (int) (imgRatio * actualWidth);
                actualHeight = (int) maxHeight;
            } else if (imgRatio > maxRatio) {
                imgRatio = maxWidth / actualWidth;
                actualHeight = (int) (imgRatio * actualHeight);
                actualWidth = (int) maxWidth;
            } else {
                actualHeight = (int) maxHeight;
                actualWidth = (int) maxWidth;

            }
        }

        //  setting inSampleSize value allows to load a scaled down version of the original image

        options.inSampleSize = calculateInSampleSize(options, actualWidth, actualHeight);

        //  inJustDecodeBounds set to false to load the actual bitmap
        options.inJustDecodeBounds = false;

        // this options allow android to claim the bitmap memory if it runs low on memory

        options.inPurgeable = true;
        options.inInputShareable = true;
        options.inTempStorage = new byte[16 * 1024];

        try {
            //  load the bitmap from its path
            bmp = BitmapFactory.decodeFile(filePath, options);
        } catch (OutOfMemoryError exception) {
            exception.printStackTrace();

        }
        try {
            scaledBitmap = Bitmap.createBitmap(actualWidth, actualHeight, Bitmap.Config.ARGB_8888);
        } catch (OutOfMemoryError exception) {
            exception.printStackTrace();
        }

        float ratioX = actualWidth / (float) options.outWidth;
        float ratioY = actualHeight / (float) options.outHeight;
        float middleX = actualWidth / 2.0f;
        float middleY = actualHeight / 2.0f;

        Matrix scaleMatrix = new Matrix();
        scaleMatrix.setScale(ratioX, ratioY, middleX, middleY);

        Canvas canvas = new Canvas(scaledBitmap);
        canvas.setMatrix(scaleMatrix);
        canvas.drawBitmap(bmp, middleX - bmp.getWidth() / 2, middleY - bmp.getHeight() / 2, new Paint(Paint.FILTER_BITMAP_FLAG));

        // check the rotation of the image and display it properly

        ExifInterface exif;
        try {
            exif = new ExifInterface(filePath);

            int orientation = exif.getAttributeInt(
                    ExifInterface.TAG_ORIENTATION, 0);
            Log.d("EXIF", "Exif: " + orientation);
            Matrix matrix = new Matrix();
            if (orientation == 6) {
                matrix.postRotate(90);
                Log.d("EXIF", "Exif: " + orientation);
            } else if (orientation == 3) {
                matrix.postRotate(180);
                Log.d("EXIF", "Exif: " + orientation);
            } else if (orientation == 8) {
                matrix.postRotate(270);
                Log.d("EXIF", "Exif: " + orientation);
            }
            scaledBitmap = Bitmap.createBitmap(scaledBitmap, 0, 0, scaledBitmap.getWidth(), scaledBitmap.getHeight(), matrix,
                    true);

            return scaledBitmap;
        } catch (IOException e) {
            e.printStackTrace();
        }

        return null;
    }

    /**
     * Get RealPath from Content URI
     *
     * @param contentURI
     * @return
     */
    private String getRealPathFromURI(String contentURI) {
        Uri contentUri = Uri.parse(contentURI);
        Cursor cursor = context.getContentResolver().query(contentUri, null, null, null, null);
        if (cursor == null) {
            return contentUri.getPath();
        } else {
            cursor.moveToFirst();
            int index = cursor.getColumnIndex(MediaStore.Images.ImageColumns.DATA);
            return cursor.getString(index);
        }
    }


    /**
     * ImageSize Calculation
     *
     * @param options
     * @param reqWidth
     * @param reqHeight
     * @return
     */

    public int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) {
        final int height = options.outHeight;
        final int width = options.outWidth;
        int inSampleSize = 1;

        if (height > reqHeight || width > reqWidth) {
            final int heightRatio = Math.round((float) height / (float) reqHeight);
            final int widthRatio = Math.round((float) width / (float) reqWidth);
            inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
        }
        final float totalPixels = width * height;
        final float totalReqPixelsCap = reqWidth * reqHeight * 2;
        while (totalPixels / (inSampleSize * inSampleSize) > totalReqPixelsCap) {
            inSampleSize++;
        }

        return inSampleSize;
    }

    /**
     * Launch Camera
     *
     * @param from
     */

    public void launchCamera(int from) {
        this.from = from;

        if (Build.VERSION.SDK_INT >= 23) {
            permission_check(1);
        } else {
            camera_call();
        }
    }

    /**
     * Launch Gallery
     *
     * @param from
     */

    public void launchGallery(int from) {

        this.from = from;

        if (Build.VERSION.SDK_INT >= 23) {
            permission_check(2);
        } else {
            galley_call();
        }
    }

    /**
     * Show AlertDialog with the following options
     * <p>
     * Camera
     * Gallery
     *
     * @param from
     */

    public void imagepicker(final int from) {
        this.from = from;

        final CharSequence[] items;

        if (isDeviceSupportCamera()) {
            items = new CharSequence[2];
            items[0] = "Camera";
            items[1] = "Gallery";
        } else {
            items = new CharSequence[1];
            items[0] = "Gallery";
        }

        android.app.AlertDialog.Builder alertdialog = new android.app.AlertDialog.Builder(current_activity);
        alertdialog.setTitle("Add Image");
        alertdialog.setItems(items, new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int item) {
                if (items[item].equals("Camera")) {
                    launchCamera(from);
                } else if (items[item].equals("Gallery")) {
                    launchGallery(from);
                }
            }
        });
        alertdialog.show();
    }

    /**
     * Check permission
     *
     * @param code
     */

    public void permission_check(final int code) {
        int hasWriteContactsPermission = ContextCompat.checkSelfPermission(current_activity,
                Manifest.permission.WRITE_EXTERNAL_STORAGE);

        if (hasWriteContactsPermission != PackageManager.PERMISSION_GRANTED) {
            if (!ActivityCompat.shouldShowRequestPermissionRationale(current_activity,
                    Manifest.permission.WRITE_EXTERNAL_STORAGE)) {

                showMessageOKCancel("For adding images , You need to provide permission to access your files",
                        new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {

                                ActivityCompat.requestPermissions(current_activity,
                                        new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                                        code);
                            }
                        });
                return;
            }

            ActivityCompat.requestPermissions(current_activity,
                    new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                    code);
            return;
        }

        if (code == 1)
            camera_call();
        else if (code == 2)
            galley_call();
    }


    private void showMessageOKCancel(String message, DialogInterface.OnClickListener okListener) {
        new AlertDialog.Builder(current_activity)
                .setMessage(message)
                .setPositiveButton("OK", okListener)
                .setNegativeButton("Cancel", null)
                .create()
                .show();
    }


    /**
     * Capture image from camera
     */

    public void camera_call() {
        ContentValues values = new ContentValues();
        imageUri = current_activity.getContentResolver().insert(
                MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
        Intent intent1 = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        intent1.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
        current_activity.startActivityForResult(intent1, 0);
    }

    /**
     * pick image from Gallery
     */

    public void galley_call() {

        Intent intent2 = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
        intent2.setType("image/*");
        current_activity.startActivityForResult(intent2, 1);

    }


    /**
     * Activity PermissionResult
     *
     * @param requestCode
     * @param permissions
     * @param grantResults
     */
    public void request_permission_result(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        switch (requestCode) {
            case 1:
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    camera_call();
                } else {
                    Toast.makeText(current_activity, "Permission denied", Toast.LENGTH_LONG).show();
                }
                break;

            case 2:
                // If request is cancelled, the result arrays are empty.
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    galley_call();
                } else {

                    Toast.makeText(current_activity, "Permission denied", Toast.LENGTH_LONG).show();
                }
                break;
        }
    }


    /**
     * Intent ActivityResult
     *
     * @param requestCode
     * @param resultCode
     * @param data
     */
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        String file_name;
        Bitmap bitmap;

        switch (requestCode) {
            case 0:

                if (resultCode == current_activity.RESULT_OK) {

                    Log.i("Camera Selected", "Photo");

                    try {
                        selected_path = null;
                        selected_path = getPath(imageUri);
                        // Log.i("selected","path"+selected_path);
                        file_name = selected_path.substring(selected_path.lastIndexOf("/") + 1);
                        // Log.i("file","name"+file_name);
                        bitmap = compressImage(imageUri.toString(), 816, 612);
                        imageAttachment_callBack.image_attachment(from, file_name, bitmap, imageUri);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }


                }
                break;
            case 1:
                if (resultCode == current_activity.RESULT_OK) {
                    Log.i("Gallery", "Photo");
                    Uri selectedImage = data.getData();

                    try {
                        selected_path = null;
                        selected_path = getPath(selectedImage);
                        file_name = selected_path.substring(selected_path.lastIndexOf("/") + 1);
                        bitmap = compressImage(selectedImage.toString(), 816, 612);
                        imageAttachment_callBack.image_attachment(from, file_name, bitmap, selectedImage);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }


                }
                break;
        }


    }

    /**
     * Get image from Uri
     *
     * @param uri
     * @param height
     * @param width
     * @return
     */
    public Bitmap getImage_FromUri(Uri uri, float height, float width) {
        Bitmap bitmap = null;

        try {
            bitmap = compressImage(uri.toString(), height, width);
        } catch (Exception e) {
            e.printStackTrace();
        }

        return bitmap;
    }

    /**
     * Get filename from URI
     *
     * @param uri
     * @return
     */
    public String getFileName_from_Uri(Uri uri) {
        String path = null, file_name = null;

        try {

            path = getRealPathFromURI(uri.getPath());
            file_name = path.substring(path.lastIndexOf("/") + 1);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }

        return file_name;

    }


    /**
     * Check Image Exist (or) Not
     *
     * @param file_name
     * @param file_path
     * @return
     */

    public boolean checkimage(String file_name, String file_path) {
        boolean flag;
        path = new File(file_path);

        File file = new File(path, file_name);
        if (file.exists()) {
            Log.i("file", "exists");
            flag = true;
        } else {
            Log.i("file", "not exist");
            flag = false;
        }

        return flag;
    }


    /**
     * Get Image from the given path
     *
     * @param file_name
     * @param file_path
     * @return
     */

    public Bitmap getImage(String file_name, String file_path) {

        path = new File(file_path);
        File file = new File(path, file_name);

        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inPreferredConfig = Bitmap.Config.ARGB_8888;
        options.inSampleSize = 2;
        options.inTempStorage = new byte[16 * 1024];

        Bitmap bitmap = BitmapFactory.decodeFile(file.getAbsolutePath(), options);

        if (bitmap != null)
            return bitmap;
        else
            return null;
    }

    /**
     * Create an image
     *
     * @param bitmap
     * @param file_name
     * @param filepath
     * @param file_replace
     */


    public void createImage(Bitmap bitmap, String file_name, String filepath, boolean file_replace) {

        path = new File(filepath);

        if (!path.exists()) {
            path.mkdirs();
        }

        File file = new File(path, file_name);

        if (file.exists()) {
            if (file_replace) {
                file.delete();
                file = new File(path, file_name);
                store_image(file, bitmap);
                Log.i("file", "replaced");
            }
        } else {
            store_image(file, bitmap);
        }

    }


    /**
     * @param file
     * @param bmp
     */
    public void store_image(File file, Bitmap bmp) {
        try {
            FileOutputStream out = new FileOutputStream(file);
            bmp.compress(Bitmap.CompressFormat.PNG, 80, out);
            out.flush();
            out.close();

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // Image Attachment Callback

    public interface ImageAttachmentListener {
        public void image_attachment(int from, String filename, Bitmap file, Uri uri);
    }

}

Step 3: Android Manifest
Open AndroidManifest.java add the WRITE_EXTERNAL_STORAGE permission.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.prasad.imagepickerex">

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

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>