cannot find symbol variable mediaStore

/**
 * The {@link android.support.v4.view.PagerAdapter} that will provide
 * fragments for each of the sections. We use a
 * {@link FragmentPagerAdapter} derivative, which will keep every
 * loaded fragment in memory. If this becomes too memory intensive, it
 * may be best to switch to a
 * {@link android.support.v13.app.FragmentStatePagerAdapter}.
 */
SectionsPagerAdapter mSectionsPagerAdapter;

/**
 * The {@link ViewPager} that will host the section contents.
 */
ViewPager mViewPager;
public static final String TAG = MainActivity.class.getSimpleName();

public final static int TAKE_PHOTO_REQUEST = 0;
public final static int TAKE_VIDEO_REQUEST = 1;
public final static int CHOOSE_PHOTO_REQUEST = 2;
public final static int CHOOSE_VIDEO_REQUEST = 3;

// Implement OnClick Listener for User Clicking on an Item in the Dialog List
protected DialogInterface.OnClickListener mDialogListener = new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialog, int which) {
        switch (which){
            case 0: //Take Picture
                // create Intent to take a picture and return control to the calling application
                Intent takePhotoIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                // start the image capture Intent
                startActivityForResult(takePhotoIntent, TAKE_PHOTO_REQUEST);
                break;
            case 1: //Take Video
                break;
            case 2: //Choose Picture
                break;
            case 3: //Choose Picture
                break;
        }
    }
};


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

    // This allows progress bar to be called in Fragments (Inbox and Friends)
    requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
    setContentView(R.layout.activity_main);

    // Whenever you use any signup or login methods, the user is cached on disk. By using the
    // cached currentUser object, the user does not have to login every time he opens the app
    ParseUser currentUser = ParseUser.getCurrentUser();
    if (currentUser == null) {
        navigateToLogin();
    }
    else {
        Log.i(TAG,currentUser.getUsername());
    }


    // Set up the action bar.
    final ActionBar actionBar = getActionBar();
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

    // Create the adapter that will return a fragment for each of the
    // primary sections of the activity.
    mSectionsPagerAdapter = new SectionsPagerAdapter(this, getSupportFragmentManager());

    // Set up the ViewPager with the sections adapter.
    mViewPager = (ViewPager) findViewById(R.id.pager);
    mViewPager.setAdapter(mSectionsPagerAdapter);

    // When swiping between different sections, select the corresponding
    // tab. We can also use ActionBar.Tab#select() to do this if we have
    // a reference to the Tab.
    mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
        @Override
        public void onPageSelected(int position) {
            actionBar.setSelectedNavigationItem(position);
        }
    });

    // For each of the sections in the app, add a tab to the action bar.
    for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
        // Create a tab with text corresponding to the page title defined by
        // the adapter. Also specify this Activity object, which implements
        // the TabListener interface, as the callback (listener) for when
        // this tab is selected.
        actionBar.addTab(
                actionBar.newTab()
                        .setText(mSectionsPagerAdapter.getPageTitle(i))
                        .setTabListener(this));
    }
}

private void navigateToLogin() {
    // The user is directed to Login Page
    Intent intent = new Intent(this, LoginActivity.class);

    // This removes MainActivity and set the LoginActivity at the bottom of the Stack
    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);

    startActivity(intent);
}


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

@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();

    switch (id){
        case R.id.action_logout:   // User wants to log out
        ParseUser.logOut();
        navigateToLogin();
        return true;

        case R.id.action_edit_friends:   //User wants to Edit Friends List
        Intent intent = new Intent(this, EditFriendsActivity.class);
        startActivity(intent);

        case R.id.action_camera:    //User wants to add picture or video
            AlertDialog.Builder builder = new AlertDialog.Builder(this);
            builder.setItems(R.array.camera_choices,mDialogListener);
            AlertDialog dialog = builder.create();
            dialog.show();
    }
    return super.onOptionsItemSelected(item);
}

// These methods are associated with ActionBar.TabListener
@Override
public void onTabSelected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
    // When the given tab is selected, switch to the corresponding page in
    // the ViewPager.
    mViewPager.setCurrentItem(tab.getPosition());
}

@Override
public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
}

@Override
public void onTabReselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
}