Ribbit Android app

package com.example.salman.ribbit;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.Window;
import android.widget.Button;
import android.widget.TextView;

import com.parse.LogInCallback;
import com.parse.ParseException;
import com.parse.ParseUser;


public class LogInActivity extends Activity {

    protected TextView mSignUP;
    protected TextView userNameL;
    protected TextView passowrdL;

    protected Button logInButton;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
       requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
        setContentView(R.layout.loginactivity);

        mSignUP = (TextView) findViewById(R.id.signup);

        userNameL = (TextView) findViewById(R.id.userNameField);
        passowrdL = (TextView) findViewById(R.id.passwordField);
        logInButton = (Button) findViewById(R.id.login_button);

        mSignUP.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(LogInActivity.this,Signup.class);
                 startActivity(intent);


            }
        });

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

                String muserName = userNameL.getText().toString();
                String mPassword = passowrdL.getText().toString();

                muserName= muserName.trim();

                mPassword = mPassword.trim();


                if(muserName.isEmpty() || mPassword.isEmpty())
                {
                    AlertDialog.Builder Builder = new AlertDialog.Builder (LogInActivity.this);
                    Builder.setMessage(R.string.Error);
                    Builder.setTitle(R.string.Error);
                    Builder.setPositiveButton(android.R.string.ok,null);
                    AlertDialog dialog = Builder.create();
                    dialog.show();
                }else
                {
                    setProgressBarIndeterminateVisibility(true);
                    ParseUser.logInInBackground(muserName,mPassword,new LogInCallback() {
                        @Override
                        public void done(ParseUser parseUser, ParseException e) {
                            if(e == null)
                            {
                                setProgressBarIndeterminate(false);
                                Intent intent = new Intent(LogInActivity.this,MainActivity.class);
                                intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                                intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
                                startActivity(intent);


                            }  else
                            { setProgressBarIndeterminate(false);
                                AlertDialog.Builder Builder = new AlertDialog.Builder (LogInActivity.this);
                                Builder.setMessage(R.string.Error);
                                Builder.setTitle(R.string.Error);
                                Builder.setPositiveButton(android.R.string.ok,null);
                                AlertDialog dialog = Builder.create();
                                dialog.show();
                            }
                        }
                    });



                }
            }
        });

    }


    @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_log_in, 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();

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

        return super.onOptionsItemSelected(item);
    }
}

package com.example.salman.ribbit;

import java.util.Locale;

import android.app.Activity;
import android.app.ActionBar;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.content.Intent;
import android.nfc.Tag;
import android.support.v13.app.FragmentPagerAdapter;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.util.Log;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import com.parse.ParseUser;


public class MainActivity extends Activity implements ActionBar.TabListener {

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

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

        ParseUser currentUser = new 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 three
        // primary sections of the activity.
        mSectionsPagerAdapter = new SectionsPagerAdapter(getFragmentManager());

        // 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));
        }
    }


    @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);
        return true;
    }



    @Override
    public boolean onOptionsItemSelected(MenuItem item)
    {
        int itemId = item.getItemId();

        if( itemId == R.id.Logout_menu )
        {
            ParseUser.logOut();
            navigateToLogin();


        }

        return super.onOptionsItemSelected(item);
    }

    public void navigateToLogin() {
        Intent intent = new Intent(this, LogInActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);

        startActivity(intent);
    }



    @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) {
    }

    /**
     * A {@link FragmentPagerAdapter} that returns a fragment corresponding to
     * one of the sections/tabs/pages.
     */
    public class SectionsPagerAdapter extends FragmentPagerAdapter {

        public SectionsPagerAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int position) {
            // getItem is called to instantiate the fragment for the given page.
            // Return a PlaceholderFragment (defined as a static inner class below).
            return PlaceholderFragment.newInstance(position + 1);
        }

        @Override
        public int getCount() {
            // Show 3 total pages.
            return 3;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            Locale l = Locale.getDefault();
            switch (position) {
                case 0:
                    return getString(R.string.title_section1).toUpperCase(l);
                case 1:
                    return getString(R.string.title_section2).toUpperCase(l);
                case 2:
                    return getString(R.string.title_section3).toUpperCase(l);
            }
            return null;
        }
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment {
        /**
         * The fragment argument representing the section number for this
         * fragment.
         */
        private static final String ARG_SECTION_NUMBER = "section_number";

        /**
         * Returns a new instance of this fragment for the given section
         * number.
         */
        public static PlaceholderFragment newInstance(int sectionNumber) {
            PlaceholderFragment fragment = new PlaceholderFragment();
            Bundle args = new Bundle();
            args.putInt(ARG_SECTION_NUMBER, sectionNumber);
            fragment.setArguments(args);
            return fragment;
        }

        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_main, container, false);
            return rootView;
        }
    }

}