While creating list on a recycler view we need more functionality like delete, copy and more. Like our popular apps what's app, gmail and hike we found toolbar in action mode if we long press list items on that, same UI with functionality we will implement using the contextual action mode. Below steps will help you to implement this Toolbar Action Mode.

Step1: Starting with a recycler view layout in a xml file

 <android.support.v7.widget.RecyclerView
        android:id="@+id/recyclerView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scrollbars="none" />

Step2: Initializing recycler view

recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
        recyclerView.setHasFixedSize(true);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));

	// creating model class(Item_Model) with two string variables title and sub_title
        // array_list to set row entries
        item_models = new ArrayList<>();
        for (int i = 1; i <= 40; i++)
            item_models.add(new Item_Model("Title of row" + i, "Sub Title of a row" + i));

        adapter = new RecyclerView_Adapter(ActionModeActivity.this, item_models);
        recyclerView.setAdapter(adapter);
        adapter.notifyDataSetChanged();

Step3: Implement item click and long click over recycler view

private void implementRecyclerViewClickListeners() {
        recyclerView.addOnItemTouchListener(new RecyclerTouchListener(this, recyclerView, new RecyclerClick_Listener() {
            @Override
            public void onClick(View view, int position) {
                //If ActionMode not null select item
                if (mActionMode != null)
                    onListItemSelect(position);
            }

            @Override
            public void onLongClick(View view, int position) {
                //Select item on long click
                onListItemSelect(position);
            }
        }));
    }

    //List item select method
    private void onListItemSelect(int position) {

        adapter.toggleSelection(position);//Toggle the selection
        boolean hasCheckedItems = adapter.getSelectedCount() > 0;//Check if any items are already selected or not

        if (hasCheckedItems && mActionMode == null)
            // there are some selected items, start the actionMode
            mActionMode = ((AppCompatActivity) this).startSupportActionMode(new Toolbar_ActionMode_Callback(this, adapter, item_models, false));
        else if (!hasCheckedItems && mActionMode != null)
            // there no selected items, finish the actionMode
            mActionMode.finish();

        if (mActionMode != null)
            //set action mode title on item selection
            mActionMode.setTitle(String.valueOf(adapter.getSelectedCount()) + " selected");
    }

    //Set action mode null after use
    public static void setNullToActionMode() {
        if (mActionMode != null)
            mActionMode = null;
    }

    //Delete selected rows
    public static void deleteRows() {

        SparseBooleanArray selected = adapter.getSelectedIds();//Get selected ids

        //Loop all selected ids
        for (int i = (selected.size() - 1); i >= 0; i--) {
            if (selected.valueAt(i)) {
                //If current id is selected remove the item via key
                item_models.remove(selected.keyAt(i));
                adapter.notifyDataSetChanged();//notify adapter

            }
        }
        Toast.makeText(this, selected.size() + " item deleted.", Toast.LENGTH_SHORT).show();//Show Toast
        mActionMode.finish();//Finish action mode after use
    }

Step4: Now creating adapter class RecyclerView_Adapter with removing seleted items methods

//Remove selected selections
    public void removeSelection() {
        mSelectedItemsIds = new SparseBooleanArray();
        notifyDataSetChanged();
    }

    //Put or delete selected position into SparseBooleanArray
    public void selectView(int position, boolean value) {
        if (value)
            mSelectedItemsIds.put(position, value);
        else
            mSelectedItemsIds.delete(position);

        notifyDataSetChanged();
    }

Step5: Interface for communication

public interface RecyclerClick_Listener {
    void onClick(View view, int position);
    void onLongClick(View view, int position);
}

Step6: Now creating touch listener class and implementing interface we created

public class RecyclerTouchListener implements RecyclerView.OnItemTouchListener {

    private GestureDetector gestureDetector;
    private RecyclerClick_Listener clickListener;

    public RecyclerTouchListener(Context context, final RecyclerView recyclerView, final RecyclerClick_Listener clickListener) {
        this.clickListener = clickListener;
        gestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
            @Override
            public boolean onSingleTapUp(MotionEvent e) {
                return true;
            }

            @Override
            public void onLongPress(MotionEvent e) {
                View child = recyclerView.findChildViewUnder(e.getX(), e.getY());
                if (child != null && clickListener != null) {
                    clickListener.onLongClick(child, recyclerView.getChildPosition(child));
                }
            }
        });
    }

    @Override
    public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {

        View child = rv.findChildViewUnder(e.getX(), e.getY());
        if (child != null && clickListener != null && gestureDetector.onTouchEvent(e)) {
            clickListener.onClick(child, rv.getChildPosition(child));
        }
        return false;
    }

    @Override
    public void onTouchEvent(RecyclerView rv, MotionEvent e) {
    }

    @Override
    public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {

    }
}

Step7: Final step is to implement menu items click listeners

public class Toolbar_ActionMode_Callback implements ActionMode.Callback {
    private Context context;
    private RecyclerView_Adapter recyclerView_adapter;
    private ArrayList<Item_Model> message_models;
    private boolean isListViewFragment;

    public Toolbar_ActionMode_Callback(Context context, RecyclerView_Adapter recyclerView_adapter, ArrayList<Item_Model> message_models, boolean isListViewFragment) {
        this.context = context;
        this.recyclerView_adapter = recyclerView_adapter;
        this.message_models = message_models;
        this.isListViewFragment = isListViewFragment;
    }

    @Override
    public boolean onCreateActionMode(ActionMode mode, Menu menu) {
        mode.getMenuInflater().inflate(R.menu.menu_main, menu);         //Inflate the menu over action mode
        return true;
    }

    @Override
    public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
        //Sometimes the meu will not be visible so for that we need to set their visibility manually in this method
        //So here show action menu according to SDK Levels
        if (Build.VERSION.SDK_INT < 11) {
            MenuItemCompat.setShowAsAction(menu.findItem(R.id.action_delete), MenuItemCompat.SHOW_AS_ACTION_NEVER);
            MenuItemCompat.setShowAsAction(menu.findItem(R.id.action_copy), MenuItemCompat.SHOW_AS_ACTION_NEVER);
            MenuItemCompat.setShowAsAction(menu.findItem(R.id.action_forward), MenuItemCompat.SHOW_AS_ACTION_NEVER);
        } else {
            menu.findItem(R.id.action_delete).setShowAsAction(MenuItem.SHOW_AS_ACTION_ALWAYS);
            menu.findItem(R.id.action_copy).setShowAsAction(MenuItem.SHOW_AS_ACTION_ALWAYS);
            menu.findItem(R.id.action_forward).setShowAsAction(MenuItem.SHOW_AS_ACTION_ALWAYS);
        }
        return true;
    }

    @Override
    public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
        switch (item.getItemId()) {
            case R.id.action_delete:
                ActionModeActivity.deleteRows();       //delete selected rows
                break;
            case R.id.action_copy:
                //Get selected ids on basis of current fragment action mode
                SparseBooleanArray selected;
                selected = recyclerView_adapter.getSelectedIds();

                int selectedMessageSize = selected.size();
                //Loop to all selected items
                for (int i = (selectedMessageSize - 1); i >= 0; i--) {
                    if (selected.valueAt(i)) {
                        //get selected data in Model
                        Item_Model model = message_models.get(selected.keyAt(i));
                        String title = model.getTitle();
                        String subTitle = model.getSubTitle();
                        //Print the data to show if its working properly or not
                        Log.e("Selected Items", "Title - " + title + "\n" + "Sub Title - " + subTitle);
                    }
                }
                Toast.makeText(context, "You selected Copy menu.", Toast.LENGTH_SHORT).show();//Show toast
                mode.finish();          //Finish action mode
                break;
            case R.id.action_forward:
                Toast.makeText(context, "You selected Forward menu.", Toast.LENGTH_SHORT).show();//Show toast
                mode.finish();          //Finish action mode
                break;
        }
        return false;
    }

    @Override
    public void onDestroyActionMode(ActionMode mode) {
        //When action mode destroyed remove selected selections and set action mode to null
        //First check current fragment action mode
        recyclerView_adapter.removeSelection();         // remove selection
        ActionModeActivity.setNullToActionMode();       //Set action mode null
    }
}