How to open Navigation Drawer with no actionbar, open with just a button

Question

I have a navigation bar without any actionbar (I don\'t want an actionbar). I\'m trying to make it so that I have a button that can open the navigation drawer.

I kn

Answer 1

I have a simpler solution which uses isDrawerOpen() of DrawerLayout.

The code below closes or opens the navigation drawer based on the drawer's current state (Opened/Closed)

Button hamMenu = findViewById(R.id.ham_menu);
hamMenu.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        DrawerLayout navDrawer = findViewById(R.id.drawer_layout);
        // If navigation drawer is not open yet, open it else close it.
        if(!navDrawer.isDrawerOpen(GravityCompat.START)) navDrawer.openDrawer(Gravity.START);
        else navDrawer.closeDrawer(Gravity.END);
    }
});

Answer 2

Kotlin Solution
If you want to open it from a fragment, you can use:

activity?.drawerLayout?.openDrawer(GravityCompat.START)

or inside the activity directly:

drawerLayout.openDrawer(GravityCompat.START)

Note:
If you are not familiar with the '?', I highly recommend reading about null saftey from kotlin's documentation (It is very short don't worry): https://kotlinlang.org/docs/reference/null-safety.html

Answer 3

I wrote an answer about this here: https://stackoverflow.com/a/18199771/880349

   //For me a better way in avoiding a `null pointer` in getting the DrawerLayout
   final DrawerLayout drawer = (DrawerLayout) getActivity().findViewById(R.id.drawer_layout);
   btn.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                            //Opens the Drawer
                drawer.openDrawer(Your View, Usually a ListView);
            }

                return false;
        });

You directly get the current drawer inside a view/fragement so that you won't get a NullPointerException

Answer 4

Thanks to @athor & @Ashish Tana.

It took me so much time to figure out the error (NullPointerException) I am getting.

Mine works this way; Instead of getView(), I use getActivity() and open the drawer by mDrawerLayout.openDrawer(Gravity.LEFT);.

mDrawerLayout = (DrawerLayout) getActivity().findViewById(R.id.drawer_layout);
final ImageButton btnOpenDrawer = (ImageButton) getView().findViewById(R.id.drawer_menu);

        btnOpenDrawer.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                mDrawerLayout.openDrawer(Gravity.LEFT);
            }
        });

Answer 5

It works on Button click

mButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            drawer.openDrawer(GravityCompat.START);

        }
    });

Answer 6

drawerLayout.openDrawer(Gravity.START);