Android - Switch ActionBar Back Button to Navigati

Question

I am having the following problem:

I know how to set up a toolbar to show a back button icon instead of a burger button icon.

From this:

to this:

using: getSupportActionBar().setDisplayHomeAsUpEnabled(true);

Now, I want to do the reverse action, I want to go from back button icon to burger icon:

to here:

How can I do this?

Update:

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

    setSupportActionBar(mToolbar);
    getSupportActionBar().setDisplayShowTitleEnabled(false);
}

private void enableViews(boolean enable) {
    if(enable) {
        // Enables back button icon
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    } else {
        // TODO: Enables burger icon
    }
}

Answer 1

I've been trying some of these examples on my App, but none of them seemed to work. I am using fragments and some of them must show the back option instead of home. Here is my implementation (in Kotlin):

override fun onResume() {
    super.onResume()
    var drawerLayout: DrawerLayout = activity.findViewById(R.id.drawer_layout)
    drawerLayout.setDrawerLockMode(DrawerLayout.LOCK_MODE_LOCKED_CLOSED)
    var actionBar = (activity as MainActivity).supportActionBar
    actionBar!!.setDisplayHomeAsUpEnabled(true)
    var  toggle= (activity as MainActivity).drawerToggle
    toggle.isDrawerIndicatorEnabled = false
    toggle.setToolbarNavigationClickListener { v ->  activity.onBackPressed() }
}

override fun onStop() {
    super.onStop()
    var drawerLayout: DrawerLayout = activity.findViewById(R.id.drawer_layout)
    drawerLayout.setDrawerLockMode(DrawerLayout.LOCK_MODE_UNLOCKED)
    var actionBar = (activity as MainActivity).supportActionBar
    actionBar!!.setDisplayHomeAsUpEnabled(false)
    var  toggle= (activity as MainActivity).drawerToggle
    toggle.setToolbarNavigationClickListener {null}
    toggle.syncState()
}

NOTE: these are the overridden onResume and onStop method inside the fragment.

REMARK: the hamburger icon will only show up if the toggle.syncState() method is called. I've been almost 24 hours figuring out why the home icon wasn't showing.

Hope my post can help someone.

Answer 2

 final Toolbar toolbar = (Toolbar) findViewById(R.id.actionbar);
      toolbar.setTitle(Html.fromHtml("<font color=#ffffff>" +     getString(R.string.print_s) + "</font>"));
      toolbar.setNavigationIcon(getResources().getDrawable(R.drawable.menu_icon));
     toolbar.setNavigationOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
             DetailActivity.this.finish();
        }
    });
    toolbar.inflateMenu(R.menu.fav);
    toolbar.setOnMenuItemClickListener(new Toolbar.OnMenuItemClickListener()     {
        @Override
        public boolean onMenuItemClick(MenuItem item) {
              item.setIcon(R.drawable.back_icon)
              return true;
            }
            return false;
        }
    });

Answer 3

If I assume you're using android.support.v4.widget.DrawerLayout in your layout, then this approach may work for you; I've only tested on API 21 but given it's mostly using the support libraries, it should work (famous last words) on lower or higher targets.

import android.support.v7.app.ActionBarDrawerToggle
import android.support.v4.widget.DrawerLayout

    ActionBarDrawerToggle mDrawerToggle;
    DrawerLayout drawerLayout;
    private boolean mToolBarNavigationListenerIsRegistered = false;

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

        setSupportActionBar(mToolbar);
        getSupportActionBar().setDisplayShowTitleEnabled(false);
        // Get DrawerLayout ref from layout
        drawerLayout = (DrawerLayout)findViewById(R.id.drawer);
        // Initialize ActionBarDrawerToggle, which will control toggle of hamburger.
        // You set the values of R.string.open and R.string.close accordingly.
        // Also, you can implement drawer toggle listener if you want.
        mDrawerToggle = new ActionBarDrawerToggle (this, drawerLayout, mToolbar, R.string.open, R.string.close);
        // Setting the actionbarToggle to drawer layout
        drawerLayout.setDrawerListener(mDrawerToggle);
        // Calling sync state is necessary to show your hamburger icon...
        // or so I hear. Doesn't hurt including it even if you find it works
        // without it on your test device(s)
        mDrawerToggle.syncState();
    }

    /**
     * To be semantically or contextually correct, maybe change the name
     * and signature of this function to something like:
     *
     * private void showBackButton(boolean show)
     * Just a suggestion.
     */
     private void enableViews(boolean enable) {

        // To keep states of ActionBar and ActionBarDrawerToggle synchronized,
        // when you enable on one, you disable on the other.
        // And as you may notice, the order for this operation is disable first, then enable - VERY VERY IMPORTANT.
        if(enable) {
            //You may not want to open the drawer on swipe from the left in this case  
            drawerLayout.setDrawerLockMode(DrawerLayout.LOCK_MODE_LOCKED_CLOSED);
            // Remove hamburger
            mDrawerToggle.setDrawerIndicatorEnabled(false);
            // Show back button
            getSupportActionBar().setDisplayHomeAsUpEnabled(true);
            // when DrawerToggle is disabled i.e. setDrawerIndicatorEnabled(false), navigation icon
            // clicks are disabled i.e. the UP button will not work.
            // We need to add a listener, as in below, so DrawerToggle will forward
            // click events to this listener.
            if(!mToolBarNavigationListenerIsRegistered) {
                mDrawerToggle.setToolbarNavigationClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        // Doesn't have to be onBackPressed
                        onBackPressed();
                    }
                });

                mToolBarNavigationListenerIsRegistered = true;
            }

        } else {
            //You must regain the power of swipe for the drawer. 
            drawerLayout.setDrawerLockMode(DrawerLayout.LOCK_MODE_UNLOCKED);

            // Remove back button
            getSupportActionBar().setDisplayHomeAsUpEnabled(false);
            // Show hamburger 
            mDrawerToggle.setDrawerIndicatorEnabled(true);
            // Remove the/any drawer toggle listener
            mDrawerToggle.setToolbarNavigationClickListener(null);
            mToolBarNavigationListenerIsRegistered = false;
        }

        // So, one may think "Hmm why not simplify to:
        // .....
        // getSupportActionBar().setDisplayHomeAsUpEnabled(enable);
        // mDrawer.setDrawerIndicatorEnabled(!enable);
        // ......
        // To re-iterate, the order in which you enable and disable views IS important #dontSimplify.
    }

The solution uses ActionBarDrawerToggle.setDrawerIndicatorEnabled to toggle the visibility of the hamburger icon and ActionBar.setDisplayHomeAsUpEnabled for visibility of the Up button, essentially making use of their respective drawable resources.

Other assumptions

• Your Activity theme extends Theme.AppCompat.Light.NoActionBar.

Answer 4

-> If you have a drawer on homeactivity and initalfragment you have to show the drawertoggle and after inner fragement you don't want to show the drawer behalf of drawer you have to show the back button and change the title of all fragement like this.

• make your actionbartoggle public in your activity.

• in your home fragment write this code.

  @Override
  
  public void onResume() 
  
  {
      super.onResume();
  
      ((HomeActivity)getActivity()).getSupportActionBar().setTitle("Home");
  
      ((HomeActivity)getActivity()).getSupportActionBar().setDisplayHomeAsUpEnabled(false);
  
      ((HomeActivity)getActivity()).actionBarDrawerToggle.setDrawerIndicatorEnabled(true);}    
  

• and in other fragments write this code :

       @Override
      public void onResume() 
  {     super.onResume();
          ((HomeActivity)getActivity()).getSupportActionBar().setTitle("My Account");
          ((HomeActivity)getActivity()).actionBarDrawerToggle.setDrawerIndicatorEnabled(false);
          ((HomeActivity)getActivity()).getSupportActionBar().setDisplayHomeAsUpEnabled(true);
      }
  

• and in your main activity write in on backpressed :

  @Override
      public void onBackPressed() 
      {
          if (getSupportFragmentManager().getBackStackEntryCount() > 0) {
  
              getSupportFragmentManager().popBackStackImmediate();
  
          } else {
  
              super.onBackPressed();
  
          }
      }