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 2020-03-10 05:30:40

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;

    }