Question

我需要在片段中使用setSupportActionBar，我无法也无法使用setContentView请帮助它也提前谢谢你给出相关代码

public class StudentrFragment extends Fragment {
        Toolbar toolbar;
        TabLayout tabLayout;
        ViewPager viewPager;
        ViewPagerAdapter viewPagerAdapter;


        public StudentrFragment() {
            // Required empty public constructor
        }


        @Override
        public void onCreate(Bundle savedInstanceState){
            super.onCreate(savedInstanceState);
            setContentView(R.layout.tabbar_layout);
            toolbar = (Toolbar) findViewById(R.id.toolbar);
            setSupportActionBar(toolbar); 
            tabLayout = (TabLayout) findViewById(R.id.tabLayout);
            viewPager = (ViewPager) findViewById(R.id.viewPager);
            viewPagerAdapter = new ViewPagerAdapter(getSupportFragmentManager());
            viewPagerAdapter.addFragments(new CivilFragment(),"Civil Dept");
            viewPagerAdapter.addFragments(new ComputerFragment(),"CSE Dept");
            viewPagerAdapter.addFragments(new EeeFragment(),"EEE Dept");
            viewPagerAdapter.addFragments(new EceFragment(),"ECE Dept");
            viewPager.setAdapter(viewPagerAdapter);
            tabLayout.setupWithViewPager(viewPager);

        }

    }

Answer 1

你可以在片段中设置这样的SupportActionbar：

((AppCompatActivity)getActivity()).setSupportActionBar(mToolbar);

您需要tabbar_layout onCreateView Fragment中的@Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.tabbar_layout, container, false); //YOUR STUFF return rootView; }。像这样：

xargs git log --decorate --no-walk=unsorted --oneline < .git/MERGE_HEAD

Answer 2

suggested solution可以工作，但是看起来并不优雅，理想情况下，片段应该不了解其父活动。另一种选择是根本不使用setSupportActionBar。如果您使用navigation库，则将Toolbar添加到片段布局并使用NavigationUI进行设置可能会更容易，例如：

<!-- my_fragment.xml -->
<androidx.constraintlayout.widget.ConstraintLayout ... >

  <com.google.android.material.appbar.MaterialToolbar
    android:id="@+id/toolbar"
    ... />

</androidx.constraintlayout.widget.ConstraintLayout>

class MyFragment : Fragment() {
  ...

  override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    super.onViewCreated(view, savedInstanceState)

    val navController = findNavController()
    binding.toolbar.setupWithNavController(navController)
  }
}

您可以找到完整的GitHub示例here。另外，请查看另一个问题Is setSupportActionbar required anymore?和我的answer，以了解更多详细信息。

Answer 3

This site has the solution which worked for me!

粘贴：

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

AppCompatActivity activity = (AppCompatActivity) getActivity();

activity.setSupportActionBar(toolbar);

如何在fragment中使用setSupportActionBar

3 个答案: