Navigationview+fragment：为什么切换一个fragment后，item无法点击。navigation的监听和fragment的切换代码如下

[fishzhazha]

时间紧迫，救救孩子

   navCehua.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
            @Override
            public boolean onNavigationItemSelected(@NonNull MenuItem menuItem) {
                switch (menuItem.getItemId()) {
                    case R.id.it_Upload:
                        tvTitle.setText("上传错题");
                        SwitchFrag(fr_u);
                        Toast.makeText(MainActivity.this,menuItem.getTitle().toString(),Toast.LENGTH_SHORT).show();
                        break;
                    case R.id.it_Calendar:
                        tvTitle.setText("考试月历");
                        SwitchFrag(fr_c);
                        break;
                    case R.id.it_Text:
                        tvTitle.setText("错题测试");
                        SwitchFrag(fr_t);
                        Toast.makeText(MainActivity.this,menuItem.getTitle().toString(),Toast.LENGTH_SHORT).show();
                        break;
                    case R.id.it_Analyse:
                        tvTitle.setText("图谱分析");
                        SwitchFrag(fr_a);
                        break;
                }

//                navCehua.getMenu().clear();
//                navCehua.inflateMenu(R.menu.cehua_menu);
//                navCehua.getMenu().findItem(menuItem.getItemId()).setChecked(true);
                drawer.closeDrawer(GravityCompat.START);
                return true;
            }
        });

    }


    //转换fragment
    public void SwitchFrag(Fragment targetFragment){

        FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
        //如果Fragment没有被添加，则添加，否则显示
        if(!targetFragment.isAdded()){

            transaction.hide(currentFragment).add(R.id.dl_cebian, targetFragment).commit();
        }
        else{
            transaction.hide(currentFragment).show(targetFragment).commit();
        }
        currentFragment = targetFragment;
    }

[拜雨自学]

NavigationUI.setupWithNavController这里面会把你的监听覆盖掉