Android : How to File Save (Screenshot) Locally Android Studio?

I'm nearing the end of an internship for app development and I was assigned to create an app from scratch, instead of porting the apple version. I am having trouble figuring out how to save an in app screenshot, and then saving it to the device. I do not want to save externally because you can't assume everyone uses an SD card.

Here is my code, when I hit send I want the screenshot generated and saved so that when I use my share intent I can send the screenshot.

import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.ShareActionProvider;
import android.support.v4.view.MenuItemCompat;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnKeyListener;
import android.widget.TextView;
import android.widget.EditText;
import android.widget.Toast;
import android.text.TextWatcher;
import android.text.Editable;
import android.graphics.Bitmap;
import android.graphics.Typeface;
import android.content.Intent;
import android.content.Context;

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

public class MainActivity extends ActionBarActivity {
TextView CodexTV;
EditText CodexET;

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

    //Loading our AvianKingdom Codex Font
    Typeface tf = Typeface.createFromAsset(getAssets(), "fonts/WWAvianKingdom-Regular.ttf");
    //Text view label
    CodexET = ((EditText) findViewById(R.id.CodexMessage));
    //REAL-TIME Textview change
    CodexET.addTextChangedListener(new TextWatcher() {
        public void afterTextChanged(Editable s) {   //Convert the Text to String
            String inputText = CodexET.getText().toString();
            CodexTV = ((TextView) findViewById(R.id.CustomFontText));
            CodexTV.setText(inputText);
        }

        public void beforeTextChanged(CharSequence s, int start, int count, int after) {
            // TODO Auto-generated method stub
        }

        public void onTextChanged(CharSequence s, int start, int before, int count) {
            // TODO Auto-generated method stub
        }
    });
    //Applying the font
    CodexET.setTypeface(tf);

    //Screenshot our Codex'ed Image
    CodexET.setOnKeyListener(new OnKeyListener() {
        public boolean onKey(View v, int keyCode, KeyEvent event) {
            if (event.getAction() == KeyEvent.ACTION_DOWN) {
                switch (keyCode) {
                    case KeyEvent.KEYCODE_DPAD_CENTER:
                        doShare(getDefaultIntent());
                        captureScreen();
                    case KeyEvent.KEYCODE_ENTER:
                        doShare(getDefaultIntent());
                        captureScreen();
                    default:
                        break;
                }
            }
            return false;
        }
    });
}

// Basic Share Intent to handle Sharing through Applications.
private Intent getDefaultIntent() {
    Intent intent = new Intent(Intent.ACTION_SEND);
    intent.setType("image/*");
    return intent;
}

private ShareActionProvider mShareActionProvider;

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

    //Locate MenuItem with ShareActionProvider
    MenuItem item = menu.findItem(R.id.menu_item_share);

    // Get the provider and hold onto it to set/change the share intent.
    mShareActionProvider = (ShareActionProvider) MenuItemCompat.getActionProvider(item);
    // Set history different from the default before getting the action
    // view since a call to MenuItemCompat.getActionView() calls
    // onCreateActionView() which uses the backing file name. Omit this
    // line if using the default share history file is desired.
    mShareActionProvider.setShareIntent(getDefaultIntent());

    // Return true to display menu
    return super.onCreateOptionsMenu(menu);
}

@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();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings)
    {
        return true;
    }

    return super.onOptionsItemSelected(item);
}

//Function for Screenshot and Saveing picture.
public void captureScreen()
{   // Image naming and path  to include sd card  appending name you choose for file.
    String fileName = "DR-CODEX";
    // create bitmap screen capture.
    View v1 = CodexET.getRootView();
    v1.setDrawingCacheEnabled(true);
    Bitmap bitmap = Bitmap.createBitmap(v1.getDrawingCache());
    v1.setDrawingCacheEnabled(false);

    OutputStream fout = null;
    File imageFile = new File (this.getFilesDir(), fileName);

    try
    {
        fout = new FileOutputStream(imageFile);
        bitmap.compress(Bitmap.CompressFormat.JPEG, 90, fout);
        fout.flush();
        fout.close();
    }
    catch (FileNotFoundException e)
    {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    catch (IOException e)
    {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

private void doShare(Intent shareintent)
{
    mShareActionProvider.setShareIntent(shareintent);
    invalidateOptionsMenu();
}