How to lock navigation drawer?

Question

In my application I am using navigation drawer and It works fine,but what I am trying to do is when Internet is not available user should not able to open navigation drawer,can any one help me how to solve this issue,the code for navigation drawer is given below..

public class MainActivity extends Activity {
private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
private ActionBarDrawerToggle mDrawerToggle;


    AlertDialogManager alert = new AlertDialogManager();


    SessionManager session;

private CharSequence mDrawerTitle;


private CharSequence mTitle;


private String[] navMenuTitles;
private TypedArray navMenuIcons;

private ArrayList<NavDrawerItem> navDrawerItems;
private NavDrawerListAdapter adapter;
private String id;
private boolean b;



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

    session = new SessionManager(getApplicationContext());

    id = getIntent().getStringExtra("id");

    System.out.println("MAIN ID : " + id);

    mTitle = mDrawerTitle = getTitle();


    navMenuTitles = getResources().getStringArray(R.array.nav_drawer_items);


    navMenuIcons = getResources()
            .obtainTypedArray(R.array.nav_drawer_icons);

    mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
    mDrawerList = (ListView) findViewById(R.id.list_slidermenu);


    b = checkInternetConnection();


    if(b!=true)
    {
        //Toast.makeText(getApplicationContext(), "No Internet Available", Toast.LENGTH_SHORT).show();

        mDrawerLayout.setDrawerLockMode(DrawerLayout.LOCK_MODE_LOCKED_CLOSED, mDrawerList);
    }
    else
    {
        System.out.println("Available");

    }
    navDrawerItems = new ArrayList<NavDrawerItem>();


    navDrawerItems.add(new NavDrawerItem(navMenuTitles[0], navMenuIcons.getResourceId(0, -1)));

    navDrawerItems.add(new NavDrawerItem(navMenuTitles[1], navMenuIcons.getResourceId(1, -1)));

    navDrawerItems.add(new NavDrawerItem(navMenuTitles[2], navMenuIcons.getResourceId(2, -1)));

    navDrawerItems.add(new NavDrawerItem(navMenuTitles[3], navMenuIcons.getResourceId(3, -1)));
    // search
    navDrawerItems.add(new NavDrawerItem(navMenuTitles[4], navMenuIcons.getResourceId(4, -1)));
    // help
    navDrawerItems.add(new NavDrawerItem(navMenuTitles[5], navMenuIcons.getResourceId(5, -1)));
    //logout

    navDrawerItems.add(new NavDrawerItem(navMenuTitles[6], navMenuIcons.getResourceId(6, -1)));
    // Recycle the typed array
    navMenuIcons.recycle();

    mDrawerList.setOnItemClickListener(new SlideMenuClickListener());

    // setting the nav drawer list adapter
    adapter = new NavDrawerListAdapter(getApplicationContext(),
            navDrawerItems);
    mDrawerList.setAdapter(adapter);


        getActionBar().setDisplayHomeAsUpEnabled(true);
            getActionBar().setHomeButtonEnabled(true);
    mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
            R.drawable.ic_drawer, //nav menu toggle icon
            R.string.app_name, // nav drawer open - description for accessibility
            R.string.app_name // nav drawer close - description for accessibility
    ) {
        public void onDrawerClosed(View view) {
            getActionBar().setTitle(mTitle);
            // calling onPrepareOptionsMenu() to show action bar icons
            invalidateOptionsMenu();
        }

        public void onDrawerOpened(View drawerView) {
            getActionBar().setTitle(mDrawerTitle);
            // calling onPrepareOptionsMenu() to hide action bar icons
            invalidateOptionsMenu();
        }
    };
    mDrawerLayout.setDrawerListener(mDrawerToggle);

    if (savedInstanceState == null) {
        // on first time display view for first nav item
        displayView(0);
    }
}



public boolean checkInternetConnection() {
    final ConnectivityManager conMgr = (ConnectivityManager) getSystemService (Context.CONNECTIVITY_SERVICE);
    if (conMgr.getActiveNetworkInfo() != null && conMgr.getActiveNetworkInfo().isAvailable() &&    conMgr.getActiveNetworkInfo().isConnected()) {
          return true;
    } else {
          System.out.println("Internet Connection Not Present");
        return false;
    }
 }



/*void Showtoast(String message) {
Toast.makeText(MainActivity.this, message, Toast.LENGTH_LONG).show();}
private Boolean exit = false;*/
@Override
public void onBackPressed() {
    // TODO Auto-generated method stub
    /*if (exit) 
    {
        finish(); // finish activity
    } else 
    {
        Toast.makeText(this, "Press Back again to Exit.",
                Toast.LENGTH_SHORT).show();
        exit = true;
        new Handler().postDelayed(new Runnable() 
        {
            @Override
            public void run()
            {
                exit = false;
            }
        }, 3 * 1000);

    }*/

     AlertDialog.Builder ald = new AlertDialog.Builder(MainActivity.this);
        ald.setTitle("Exit");
        ald.setMessage("Are you sure you want to quit.?");
        ald.setPositiveButton("Ok", new DialogInterface.OnClickListener()
        {
            @Override
            public void onClick(DialogInterface dialog, int which) 
            {
                moveTaskToBack(true);
                android.os.Process.killProcess(android.os.Process.myPid());
                System.exit(1);
            }
        });

        ald.setNegativeButton("Cancel", null);
        ald.show();
}





/**
 * Slide menu item click listener
 * */
private class SlideMenuClickListener implements
        ListView.OnItemClickListener {
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position,
            long id) {
        // display view for selected nav drawer item
        displayView(position);
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // toggle nav drawer on selecting action bar app icon/title
    if (mDrawerToggle.onOptionsItemSelected(item)) {
        return true;
    }
    // Handle action bar actions click
    switch (item.getItemId()) {
    case R.id.action_settings:
        return true;
    default:
        return super.onOptionsItemSelected(item);
    }
}


@Override
public boolean onPrepareOptionsMenu(Menu menu) {
    // if nav drawer is opened, hide the action items
    boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList);
    menu.findItem(R.id.action_settings).setVisible(!drawerOpen);
    return super.onPrepareOptionsMenu(menu);
}

/**
 * Diplaying fragment view for selected nav drawer list item
 * */
private void displayView(int position) {
    // update the main content by replacing fragments
    Fragment fragment = null;
    switch (position) {
    case 0:
        fragment = new HomeFragment();

        break;
    case 1:
        fragment = new FindPeopleFragment();

        break;
    case 2:
        fragment = new PhotosFragment();

        break;
    case 3:
        fragment = new CommunityFragment();

        break;
    case 4:
        fragment = new PagesFragment();

        break;
    case 5:
        fragment = new WhatsHotFragment();

        break;

    case 6:
        fragment=new Mylist();

        break;

    default:
        break;
    }

    if (fragment != null) {
        FragmentManager fragmentManager = getFragmentManager();
        fragmentManager.beginTransaction()
                .replace(R.id.frame_container, fragment).commit();

        // update selected item and title, then close the drawer
        mDrawerList.setItemChecked(position, true);
        mDrawerList.setSelection(position);
        setTitle(navMenuTitles[position]);
        mDrawerLayout.closeDrawer(mDrawerList);
    } else {
        // error in creating fragment
        Log.e("MainActivity", "Error in creating fragment");
    }
}

@Override
public void setTitle(CharSequence title) {
    mTitle = title;
    getActionBar().setTitle(mTitle);
}

/**
 * When using the ActionBarDrawerToggle, you must call it during
 * onPostCreate() and onConfigurationChanged()...
 */

@Override
protected void onPostCreate(Bundle savedInstanceState) {
    super.onPostCreate(savedInstanceState);
    // Sync the toggle state after onRestoreInstanceState has occurred.
    mDrawerToggle.syncState();
}

@Override
public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);
    // Pass any configuration change to the drawer toggls
    mDrawerToggle.onConfigurationChanged(newConfig);
}

Answer 1

Use lock modes for drawer. the following code I have used for the one activity and multiple fragment navigation pattern with drawer.

    @Override
public void onBackStackChanged() {

    if(FragUtils.getCurrentFragment(this,mBinding.layoutContent.getId()) instanceof DashboardFragment) {
        //show hamburger
        mDrawerToggle.setDrawerIndicatorEnabled(true);
        getSupportActionBar().setDisplayHomeAsUpEnabled(false);
        mDrawerToggle.syncState();
        mBinding.drawerLayout.setDrawerLockMode(DrawerLayout.LOCK_MODE_UNLOCKED);
        mBinding.drawerLayout.closeDrawers();
        mBinding.toolbar.setNavigationOnClickListener(v ->mBinding.drawerLayout.openDrawer(GravityCompat.START));
        refreshBtn.setVisible(true);
    }
    else{
        mDrawerToggle.setDrawerIndicatorEnabled(false);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);// show back button
        mBinding.drawerLayout.setDrawerLockMode(DrawerLayout.LOCK_MODE_LOCKED_CLOSED);
        mBinding.toolbar.setNavigationOnClickListener(v -> onBackPressed());
        refreshBtn.setVisible(false);
    }
}

Note: I have not added the dashboard to the back stack to avoid calling the back stack while the the container activity is creating and rendering the content. If I do so refreshBtn from the Option menu is null as the menu layout is not yet inflated.

Hope this may help!!!

Answer 2

Re construct the following method as follows.

@Override
public boolean onOptionsItemSelected(MenuItem item) {
// toggle nav drawer on selecting action bar app icon/title
if (mDrawerToggle.onOptionsItemSelected(item)) {
    b = checkInternetConnection();
    if(b==true)
        return true;
}
// Handle action bar actions click
switch (item.getItemId()) {
    case R.id.action_settings:
         return true;
    default:
        return super.onOptionsItemSelected(item);
}
}

Answer 3

You are just checking for the first time but you have to check it every time when user tries to open the navigation drawer

if (item.getItemId() == android.R.id.home) {
// check for internet connection in this place


}