您可以通过编程方式设置颜色。

private static void setMenuTextColor(final Context context, final Toolbar toolbar, final int menuResId, final int colorRes) {
    toolbar.post(new Runnable() {
        @Override
        public void run() {
            View settingsMenuItem =  toolbar.findViewById(menuResId);
            if (settingsMenuItem instanceof TextView) {
                if (DEBUG) {
                    Log.i(TAG, "setMenuTextColor textview");
                }
                TextView tv = (TextView) settingsMenuItem;
                tv.setTextColor(ContextCompat.getColor(context, colorRes));
            } else { // you can ignore this branch, because usually there is not the situation
                Menu menu = toolbar.getMenu();
                MenuItem item = menu.findItem(menuResId);
                SpannableString s = new SpannableString(item.getTitle());
                s.setSpan(new ForegroundColorSpan(ContextCompat.getColor(context, colorRes)), 0, s.length(), 0);
                item.setTitle(s);
            }

        }
    });
}

如果要为单个菜单项设置颜色，自定义工具栏主题不是正确的解决方案。为了实现这一点，你可以使用android:actionLayout和菜单项的动作视图。

首先为操作视图创建一个XML布局文件。在这个例子中，我们使用一个按钮作为一个动作视图:

menu_button.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button
        android:id="@+id/menuButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Done"
        android:textColor="?android:attr/colorAccent"
        style="?android:attr/buttonBarButtonStyle"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

在上面的代码片段中，我们使用android:textColor="?android:attr/colorAccent"自定义按钮文本颜色。

然后在菜单的XML布局文件中，包括app:actionLayout="@layout/menu_button"，如下所示:

main_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/menuItem"
        android:title=""
        app:actionLayout="@layout/menu_button"
        app:showAsAction="always"/>
</menu>

最后重写oncreateoptionsmmenu()方法在你的活动:

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.main_menu, menu);
    MenuItem item = menu.findItem(R.id.menuItem);
    Button saveButton = item.getActionView().findViewById(R.id.menuButton);
    saveButton.setOnClickListener(view -> {
        // Do something
    });
    return true;
}

.．.或片段:

@Override
public void onCreateOptionsMenu(@NonNull Menu menu, @NonNull MenuInflater inflater){
    inflater.inflate(R.menu.main_menu, menu);
    MenuItem item = menu.findItem(R.id.menuItem);
    Button saveButton = item.getActionView().findViewById(R.id.menuButton);
    button.setOnClickListener(view -> {
        // Do something
    });
}

有关操作视图的更多细节，请参阅Android开发者指南。

要更改菜单项文本颜色，请使用下面的代码

<style name="AppToolbar" parent="Theme.AppCompat.Light.NoActionBar">
<item name="android:itemTextAppearance">@style/menu_item_color</item>
</style>

在哪里

<style name="menu_item_color">
<item name="android:textColor">@color/app_font_color</item>
</style>

多亏了麦克斯。mussterman，这是我在第22关的解决方案:

public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu_main, menu);
    SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
    MenuItem searchMenuItem = menu.findItem(R.id.search);
    SearchView searchView = (SearchView) searchMenuItem.getActionView();
    searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
    searchView.setSubmitButtonEnabled(true);
    searchView.setOnQueryTextListener(this);
    setMenuTextColor(menu, R.id.displaySummary, R.string.show_summary);
    setMenuTextColor(menu, R.id.about, R.string.text_about);
    setMenuTextColor(menu, R.id.importExport, R.string.import_export);
    setMenuTextColor(menu, R.id.preferences, R.string.settings);
    return true;
}

private void setMenuTextColor(Menu menu, int menuResource, int menuTextResource) {
    MenuItem item = menu.findItem(menuResource);
    SpannableString s = new SpannableString(getString(menuTextResource));
    s.setSpan(new ForegroundColorSpan(Color.BLACK), 0, s.length(), 0);
    item.setTitle(s);
}

硬编码的颜色。BLACK可以成为setMenuTextColor方法的附加参数。此外，我只使用这个菜单项是android:showAsAction="never"。

我是这样编程的:

public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.changeip_card_menu, menu); 
    for(int i = 0; i < menu.size(); i++) {
        MenuItem item = menu.getItem(i);
        SpannableString spanString = new SpannableString(menu.getItem(i).getTitle().toString());
        spanString.setSpan(new ForegroundColorSpan(Color.BLACK), 0,     spanString.length(), 0); //fix the color to white
        item.setTitle(spanString);
    }
    return true;
}

Options menu in android can be customized to set the background or change the text appearance. The background and text color in the menu couldn’t be changed using themes and styles. The android source code (data\res\layout\icon_menu_item_layout.xml)uses a custom item of class “com.android.internal.view.menu.IconMenuItem”View for the menu layout. We can make changes in the above class to customize the menu. To achieve the same, use LayoutInflater factory class and set the background and text color for the view.

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.my_menu, menu);
    getLayoutInflater().setFactory(new Factory() {
        @Override
        public View onCreateView(String name, Context context, AttributeSet attrs) {
            if (name .equalsIgnoreCase(“com.android.internal.view.menu.IconMenuItemView”)) {
                try{
                    LayoutInflater f = getLayoutInflater();
                    final View view = f.createView(name, null, attrs);
                    new Handler().post(new Runnable() {
                        public void run() {
                            // set the background drawable
                            view .setBackgroundResource(R.drawable.my_ac_menu_background);

                            // set the text color
                            ((TextView) view).setTextColor(Color.WHITE);
                        }
                    });
                    return view;
                } catch (InflateException e) {
                    } catch (ClassNotFoundException e) {}
            }
            return null;
        }
    });
    return super.onCreateOptionsMenu(menu);
}