code: private void setupFab() {
  
  		Fab fab = (Fab) findViewById(R.id.fab);
  		View sheetView = findViewById(R.id.fab_sheet);
  		View overlay = findViewById(R.id.overlay);
  		int sheetColor = getResources().getColor(R.color.background_card);
  		int fabColor = getResources().getColor(R.color.theme_accent);
  
  		// Create material sheet FAB
  		materialSheetFab = new MaterialSheetFab<>(fab, sheetView, overlay, sheetColor, fabColor);
  
  		// Set material sheet event listener
  		materialSheetFab.setEventListener(new MaterialSheetFabEventListener() {
  			@Override
  			public void onShowSheet() {
  				// Save current status bar color
  				statusBarColor = getStatusBarColor();
  				// Set darker status bar color to match the dim overlay
  				setStatusBarColor(getResources().getColor(R.color.theme_primary_dark2));
  			}
  
  			@Override
  			public void onHideSheet() {
  				// Restore status bar color
  				setStatusBarColor(statusBarColor);
  			}
  		});
  
  		// Set material sheet item click listeners
  		findViewById(R.id.fab_sheet_item_recording).setOnClickListener(this);
  		findViewById(R.id.fab_sheet_item_reminder).setOnClickListener(this);
  		findViewById(R.id.fab_sheet_item_photo).setOnClickListener(this);
  		findViewById(R.id.fab_sheet_item_note).setOnClickListener(this);
  	}
docs: Sets up the Floating action button.