I used this code in my oncreate function to open the navigation drawer by pressing the app icon.
ActionBarDrawerToggle mDrawerToggle = new ActionBarDrawerTog
Just to echo @CommonsWare answer. Instead of findViewById(R.id.left_drawer) just do R.id.left_drawer
So the final result would look like this:
ActionBarDrawerToggle mDrawerToggle = new ActionBarDrawerToggle(
this, /* host Activity */
R.drawable.ic_drawer, /* nav drawer icon to replace 'Up' caret */
R.string.drawer_open, /* "open drawer" description */
R.string.drawer_close /* "close drawer" description */
)