code: private int getActionBarHeight() {
          int actionBarHeight = 0;
  
          try {
              if (mToolbar != null) {
                  actionBarHeight = mToolbar.getHeight();
              } else if (mHoldingActivity instanceof ActionBarActivity) {
                  ActionBar supportActionBar
                      = ((ActionBarActivity) mHoldingActivity).getSupportActionBar();
                  if (supportActionBar != null) {
                      actionBarHeight = supportActionBar.getHeight();
                  }
              } else if (mHoldingActivity instanceof AppCompatActivity) {
                  ActionBar supportActionBar
                      = ((AppCompatActivity) mHoldingActivity).getSupportActionBar();
                  if (supportActionBar != null) {
                      actionBarHeight = supportActionBar.getHeight();
                  }
              } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
                  android.app.ActionBar actionBar = mHoldingActivity.getActionBar();
                  if (actionBar != null) {
                      actionBarHeight = actionBar.getHeight();
                  }
              }
          } catch (NoClassDefFoundError e) {
              if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
                  android.app.ActionBar actionBar = mHoldingActivity.getActionBar();
                  if (actionBar != null) {
                      actionBarHeight = actionBar.getHeight();
                  }
              }
          }
          return actionBarHeight;
      }
docs: Retrieve action bar height.
  
  @return action bar height in px.