Problem with Android Lollipop ( 5.1.1) Action Bar and Tool Bar

PROBLEM: Hamburger icon in the ActionBar/ToolBar is not clickable, but a swipe from the left displays the drawer layout with menu items.
RESOLUTION: Use the CORRECT constructor for ActionBarDrawerToggle:

ActionBarDrawerToggle (Activity activity, 

                DrawerLayout drawerLayout, 

                Toolbar toolbar, ◄ - THIS IS THE KEY. Previously missing.

                int openDrawerContentDescRes, 

                int closeDrawerContentDescRes)


The main activity should extend AppCompatActivity.


and create an instance of android.support.v7.widget.Toolbar


There are plenty of full code examples online but remember to  setSupportActionBar(toolbar); and that is it!


BTW


Here is what my build.gradle looks like:

...

android { 

compileSdkVersion 21 

buildToolsVersion "21.1.0" 

...

minSdkVersion 11

targetSdkVersion 21 

...