MenuItem 没有出现在工具栏中

Question

我遇到了问题。我无法制作工具栏来显示菜单。我知道这个问题之前曾在这里被问过，我经历了所有可能的解决方案，但其中 none 给了我想要的结果。所以我使用 1 activity 和几个片段，我想根据片段在工具栏中显示不同的菜单项。这是我的 MainActivity.java

import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.Toast;

import com.google.android.material.bottomnavigation.BottomNavigationView;
import com.google.android.material.navigation.NavigationView;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import androidx.constraintlayout.widget.ConstraintLayout;
import androidx.core.view.GravityCompat;
import androidx.drawerlayout.widget.DrawerLayout;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import androidx.navigation.fragment.NavHostFragment;
import androidx.navigation.ui.AppBarConfiguration;
import androidx.navigation.ui.NavigationUI;

public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener{

    DrawerLayout drawerLayout;
    NavigationView drawerView;
    NavController navController;
    AppBarConfiguration appBarConfiguration;
    ConstraintLayout container;
    Toolbar toolbar;

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


        drawerLayout = findViewById(R.id.drawer_layout);
        drawerView = findViewById(R.id.drawer_view);
        toolbar = findViewById(R.id.toolbar);
        BottomNavigationView navView = findViewById(R.id.nav_view);
        container = findViewById(R.id.container);

        drawerView.bringToFront();
        NavHostFragment navHostFragment = (NavHostFragment) getSupportFragmentManager()
                .findFragmentById(R.id.nav_host_fragment);

        navController = navHostFragment.getNavController();
        //NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
        appBarConfiguration = new AppBarConfiguration.Builder(R.id.navigation_main, R.id.navigation_favourite,
                R.id.navigation_add_announce,R.id.navigation_notifications,
                R.id.navigation_profile).setOpenableLayout(drawerLayout).build();

        NavigationUI.setupWithNavController(drawerView, navController);
        NavigationUI.setupWithNavController(toolbar, navController, appBarConfiguration);
        NavigationUI.setupWithNavController(navView, navController);
        drawerView.setCheckedItem(R.id.drawer_main);
        drawerView.setNavigationItemSelectedListener(this);
        animateDrawer();

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.profile_fragment_menu, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        navController = Navigation.findNavController(this, R.id.nav_host_fragment);
        return NavigationUI.onNavDestinationSelected(item, navController)
                || super.onOptionsItemSelected(item);
    }

我想在 ProfileFragment 工具栏中显示登录文本 ProfileFragment.java代码：


import androidx.appcompat.widget.Toolbar;
import androidx.fragment.app.FragmentManager;
import androidx.lifecycle.ViewModelProvider;

import android.os.Bundle;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import androidx.navigation.fragment.NavHostFragment;

import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;


public class ProfileFragment extends Fragment {

    ProfileViewModel mViewModel;

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        setHasOptionsMenu(true);
        super.onCreate(savedInstanceState);
    }

    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container,
                             @Nullable Bundle savedInstanceState) {
        mViewModel = new ViewModelProvider(this).get(ProfileViewModel.class);
        View root = inflater.inflate(R.layout.profile_fragment, container, false);



        return root;
    }

    public void onCreateOptionsMenu (Menu menu, MenuInflater inflater){
        inflater.inflate(R.menu.profile_fragment_menu, menu);
    }


}

profile_fragment_menu.xml

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">

    <item
        android:id="@+id/registerFragment"
        android:title="@string/enter_acc"<!-- LogIn -->
        app:showAsAction="always"/>

</menu>

mobile_navigation.xml 持有导航图

<?xml version="1.0" encoding="utf-8"?>
<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/mobile_navigation"
    app:startDestination="@+id/navigation_main">

    <fragment
        android:id="@+id/navigation_main"
        android:name=".ui.main.MainFragment"
        android:label="@string/nav_bar_main"
        tools:layout="@layout/main_fragment" />

    <fragment
        android:id="@+id/navigation_favourite"
        android:name=".ui.favourite.FavouriteFragment"
        android:label="@string/nav_bar_favourite"
        tools:layout="@layout/favourite_fragment" />

    <fragment
        android:id="@+id/navigation_add_announce"
        android:name=".ui.add.AddFragment"
        android:label="@string/nav_bar_add_announce"
        tools:layout="@layout/add_fragment" />

    <fragment
        android:id="@+id/navigation_notifications"
        android:name=".ui.notifications.NotificationsFragment"
        android:label="@string/nav_bar_notifications"
        tools:layout="@layout/notifications_fragment" />

    <fragment
        android:id="@+id/navigation_profile"
        android:name=".ui.profile.ProfileFragment"
        android:label="@string/nav_bar_profile"
        tools:layout="@layout/profile_fragment" >
        <action
            android:id="@+id/action_navigation_profile_to_registerFragment"
            app:destination="@id/registerFragment" />
    </fragment>
    <fragment
        android:id="@+id/registerFragment"
        android:name=".ui.profile.register.RegisterFragment"
        android:label="register_fragment"
        tools:layout="@layout/register_fragment" />
</navigation>

我在 onCreate 方法的 MainActivity 中尝试了 toolbar.inflateMenu(R.menu.profile_fragment_menu) 并且菜单项出现并且可以点击但它显示在所有片段上+ onOptionsItemSelected 没有处理点击项目。我的最后一次尝试你可以在我的代码中看到。提前谢谢你

Answer 1

如果您想将 Toolbar 用作 ActionBar 并使用 ActionBar API（作为 onCreateOptionsMenu），您必须添加 setSupportActionBar(toolbar);

   protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

否则，如果您不调用 setSupportActionBar，您可以直接使用工具栏 API，并在每个片段中使用方法 inflateMenu()。类似于：

toolbar.inflateMenu(R.menu.xxxxx)

然后使用setOnMenuItemClickListener方法设置一个clickListener。

MenuItem 没有出现在工具栏中

MenuItem doesn't appear in toolbar

java

android

android-actionbar

android-toolbar