在工具栏中设置textview值

Question

我无法在工具栏内动态设置TextView值，如果我将这段代码textbe.setText（String.valueOf（b））;放在public boolean onCreateOptionsMenu（菜单菜单）中，则不会起作用另一个地方。请帮助我，这是我的代码：

package com.example.to.maimoon;

import android.database.Cursor;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutCompat;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.View;
import android.support.design.widget.TabLayout;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.support.v4.view.ViewPager;
import android.widget.AdapterView;
import android.widget.EditText;
import android.widget.FilterQueryProvider;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.AdapterView.OnItemClickListener;
public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
    private DataBaseAdapter dbHelper;
    private int b = 24;
    private TextView textbe;


    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
        ViewPager Pager = (ViewPager) findViewById(R.id.viewpager);

        tabpagerAdapter Tabpageradapter = new tabpagerAdapter(getSupportFragmentManager());

        Pager.setAdapter(Tabpageradapter);

        tabLayout.setupWithViewPager(Pager);

        textbe.setText(String.valueOf(b));

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.setDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);
    }

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        getMenuInflater().inflate(R.menu.main, menu);
        RelativeLayout badgeLayout = (RelativeLayout)menu.findItem(R.id.count_ligne).getActionView();
     textbe = (TextView) badgeLayout.findViewById(R.id.isa);

        return true ;
    }

    @Override
  public boolean onOptionsItemSelected(MenuItem item) {

        int id = item.getItemId();


        if (id == R.id.count_ligne) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {

        int id = item.getItemId();

        if (id == R.id.nav_camera) {

        } else if (id == R.id.nav_gallery) {

        } else if (id == R.id.nav_slideshow) {

        } else if (id == R.id.nav_manage) {

        } else if (id == R.id.nav_share) {

        } else if (id == R.id.nav_send) {

        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }


}