如何将工具栏添加到 android 中的片段?

How to add Toolbar to a fragment in android?

我有一个名为 HomeFragment.java 的片段,它扩展了片段 class。

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.widget.Toolbar;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import com.example.android.test.R;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.Toolbar;

public class HomeFragment extends Fragment {

    private Toolbar toolbar;
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View view = inflater.inflate(R.layout.fragment_profile,container,false);
        toolbar = (Toolbar) view.findViewById(R.id.toolbar);
        getActivity().setSupportActionController(toolbar);
        //setSupportActionBar(toolbar);
        return view;
    }
}

但我在行中收到错误:

getActivity().setSupportActionController(toolbar)

错误是:

Cannot resolve method 'setSupportActionController(android.support.v7.widget.Toolbar)'

并且有一个条件我不能将我的HomeFragment扩展到AppCombatActivity .它必须仅保留为 Fragment,即 public class HomeFragment extends Fragment.

条件是因为这段代码中的第5行

    Runnable mPendingRunnable = new Runnable() {
        @Override
        public void run() {
            // update the main content by replacing fragments
            Fragment fragment = getHomeFragment();
            FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
            fragmentTransaction.setCustomAnimations(android.R.anim.fade_in,
                    android.R.anim.fade_out);
            fragmentTransaction.replace(R.id.frame, fragment, CURRENT_TAG);
            fragmentTransaction.commitAllowingStateLoss();
        }
    };

    // If mPendingRunnable is not null, then add to the message queue
    if (mPendingRunnable != null) {
        mHandler.post(mPendingRunnable);
    }

    // show or hide the fab button
    toggleFab();

    //Closing drawer on item click
    drawer.closeDrawers();

    // refresh toolbar menu
    invalidateOptionsMenu();
}

我的 getHomeFragment() 是:

    private Fragment getHomeFragment() {
    switch (navItemIndex) {
        case 0:
            // home
            HomeFragment homeFragment = new HomeFragment();
            return homeFragment;
        case 1:
            // photos
            PhotosFragment photosFragment = new PhotosFragment();
            return photosFragment;
        case 2:
            // movies fragment
            MoviesFragment moviesFragment = new MoviesFragment();
            return moviesFragment;
        case 3:
            // notifications fragment
            NotificationsFragment notificationsFragment = new NotificationsFragment();
            return notificationsFragment;

        case 4:
            // settings fragment
            SettingsFragment settingsFragment = new SettingsFragment();
            return settingsFragment;
        default:
            return new HomeFragment();
    }
}

因此,如果我将 public class HomeFragment extends Fragment 更改为 public class HomeFragment extends AppCombatActivity,上面代码中的return语句会给出类型不兼容的错误.

请帮我解决这个错误,因为这个错误我无法制作工具栏或操作栏。 任何帮助将不胜感激。 谢谢!

先将 activity 从 getActivity() 投射到 AppCompatActivity。我认为这将解决您的错误:

((AppCompatActivity) getActivity()).getSupportActionBar(toolbar);

或者您的情况:

((AppCompatActivity) getActivity()).setSupportActionController(toolbar);

getActivity() returns a FragmentActivity 你需要得到 AppCompatActivity 返回。希望这对您有所帮助!

((AppCompatActivity)getActivity()).setSupportActionBar(editGroupTool); //toolbar id
((AppCompatActivity)getActivity()).getSupportActionBar().setTitle(" "); 
((AppCompatActivity)getActivity()).getSupportActionBar().setDisplayHomeAsUpEnabled(true);