Pick image or capture simplest way by custom 'com.kbeanie:image-chooser-library:1.5.8@aar'

ImagePickerHelper.java

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;

import com.kbeanie.imagechooser.api.ChooserType;
import com.kbeanie.imagechooser.api.ChosenImage;
import com.kbeanie.imagechooser.api.ChosenImages;
import com.kbeanie.imagechooser.api.ImageChooserListener;
import com.kbeanie.imagechooser.api.ImageChooserManager;

/**
 * Usage:  Must call ImagePickerHelper.onActivityResult(), onSaveInstanceState, onRestoreInstanceState
 * To pick or capture image, just call showDialogPickImageFrom().
 * Created by AnhNV@mwork.vn on 17/06/2016.
 */
public class ImagePickerHelper implements ImageChooserListener{
    private Activity activity;
    private OnChosenImage onChosenImage;
    private boolean isActivityResultOver = false;

    private int chooserType;
    private ImageChooserManager imageChooserManager;
    private String imagePath;

    public ImagePickerHelper(Activity activity, OnChosenImage pOnChosenImage) {
        this.onChosenImage = pOnChosenImage;
        this.activity = activity;
    }

    public ImagePickerHelper(Activity activity) {
        this(activity, null);
    }

    public String getImagePath() {
        return imagePath;
    }

    public OnChosenImage getOnChosenImage() {
        return onChosenImage;
    }

    public void setOnChosenImage(OnChosenImage onChosenImage) {
        this.onChosenImage = onChosenImage;
    }

    /**
     *
     */
    public void showDialogPickImageFrom() {
        AlertDialog.Builder builder = new AlertDialog.Builder(activity);
        builder.setTitle(R.string.pick_image_from)
                .setPositiveButton(R.string.gallery, new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        pickImage();
                    }
                })
                .setNegativeButton(R.string.take_photo, new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        captureImage();
                    }
                });
        builder.show();
    }

    /**
     *
     */
    public void pickImage() {
        chooserType = ChooserType.REQUEST_PICK_PICTURE;
        imageChooserManager = new ImageChooserManager(activity,
                ChooserType.REQUEST_PICK_PICTURE, true);
        imageChooserManager.setImageChooserListener(this);
        imageChooserManager.clearOldFiles();
        try {
            imagePath = imageChooserManager.choose();
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     *
     */
    public void captureImage() {
        chooserType = ChooserType.REQUEST_CAPTURE_PICTURE;
        imageChooserManager = new ImageChooserManager(activity,
                ChooserType.REQUEST_CAPTURE_PICTURE, true);
        imageChooserManager.setImageChooserListener(this);
        try {
            imagePath = imageChooserManager.choose();
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    private void reinitializeImageChooser() {
        imageChooserManager = new ImageChooserManager(activity, chooserType, true);
        imageChooserManager.setImageChooserListener(this);
        imageChooserManager.reinitialize(imagePath);
    }

    /**
     * Must call on Activity.onActivityResult()
     *
     * @param requestCode
     * @param resultCode
     * @param data
     */
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode == Activity.RESULT_OK &&
                (requestCode == ChooserType.REQUEST_PICK_PICTURE || requestCode == ChooserType.REQUEST_CAPTURE_PICTURE)) {
            if (imageChooserManager == null) {
                reinitializeImageChooser();
            }
            imageChooserManager.submit(requestCode, data);
        }
    }

    public void onSaveInstanceState(Bundle outState) {
        outState.putBoolean("activity_result_over", isActivityResultOver);
        outState.putInt("chooser_type", chooserType);
        outState.putString("media_path", imagePath);
    }

    public void onRestoreInstanceState(Bundle savedInstanceState) {
        if (savedInstanceState != null) {
            if (savedInstanceState.containsKey("chooser_type")) {
                chooserType = savedInstanceState.getInt("chooser_type");
            }
            if (savedInstanceState.containsKey("media_path")) {
                imagePath = savedInstanceState.getString("media_path");
            }
            if (savedInstanceState.containsKey("activity_result_over")) {
                isActivityResultOver = savedInstanceState.getBoolean("activity_result_over");
            }
        }
        if (isActivityResultOver) {
            if(onChosenImage != null) {
                onChosenImage.onChosen(imagePath);
            }
        }
    }

    @Override
    public void onImageChosen(ChosenImage chosenImage) {
        isActivityResultOver = true;
        imagePath = chosenImage.getFileThumbnail();
        if (onChosenImage != null) {
            onChosenImage.onChosen(imagePath);
        }
    }

    @Override
    public void onError(String s) {
    }

    @Override
    public void onImagesChosen(ChosenImages chosenImages) {
    }

    /**
     * Callback for public usage
     */
    public interface OnChosenImage {
        public void onChosen(String imagePath);
    }

}

MainActivity.java

public class MainActivity extends Activity implements ImagePickerHelper.OnChosenImage {
        
    ImagePickerHelper imagePickerHelper;    
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        imagePickerHelper = new ImagePickerHelper(this, this);
        findViewById(R.id.buttonPick).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                imagePickerHelper.showDialogPickImageFrom();
            }
        });
    }
    
    @Override 
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        imagePickerHelper.onActivityResult(requestCode, resultCode, data);
        super.onActivityResult(requestCode, resultCode, data);
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        imagePickerHelper.onSaveInstanceState(outState);
        super.onSaveInstanceState(outState);
    }

    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState) {
        imagePickerHelper.onRestoreInstanceState(savedInstanceState);
        super.onRestoreInstanceState(savedInstanceState);
    }
    
    @Override
    public void onChosen(final String imagePath) {
        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                //TODO Show image from imagePath
                
            }
        });
    }
}