Toolbar Navigation Hamburger Icon missing

If you want to use the same drawer as lollipop then let me tell you that's not a static image. That image is drawn in real time by a class called DrawerArrowDrawableToggle. So there is no "hamburger" icon for that.

However if you want the hamburger icon with no animation you can find it here:

https://material.io/tools/icons/?icon=menu&style=baseline

To have an animated hamburger icon you should use DrawerLayout with ActionBarDrawerToggle and enable the icon for the ActionBar and for the ActionBarDrawerToggle.

Example:

Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
DrawerLayout drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle mDrawerToggle;

setSupportActionBar(toolbar);
final ActionBar actionBar = getSupportActionBar();

if (actionBar != null)
{
   actionBar.setDisplayHomeAsUpEnabled(true);
   mDrawerToggle = new ActionBarDrawerToggle(this, drawerLayout, toolbar, R.string.hello_world, R.string.hello_world)
   {

      public void onDrawerClosed(View view)
      {
         supportInvalidateOptionsMenu();
         //drawerOpened = false;
      }

      public void onDrawerOpened(View drawerView)
      {
         supportInvalidateOptionsMenu();
         //drawerOpened = true;
      }
   };
   mDrawerToggle.setDrawerIndicatorEnabled(true);
   drawerLayout.setDrawerListener(mDrawerToggle);
   mDrawerToggle.syncState();
}

Also, you need to add these methods to your Activity:

@Override
protected void onPostCreate(Bundle savedInstanceState)
{
    super.onPostCreate(savedInstanceState);
    mDrawerToggle.syncState();
}

@Override
public void onConfigurationChanged(Configuration newConfig)
{
    super.onConfigurationChanged(newConfig);
    mDrawerToggle.onConfigurationChanged(newConfig);
}

For that you just need write to some lines

   DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
   ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
   drawer.addDrawerListener(toggle);
   toggle.setDrawerIndicatorEnabled(true);
   toggle.syncState();

toggle.setDrawerIndicatorEnabled(true); if this is false make it true or remove this line