这是你如何用颜色给一个特定的菜单项上色，适用于所有API级别:

public static void setToolbarMenuItemTextColor(final Toolbar toolbar,
                                               final @ColorRes int color,
                                               @IdRes final int resId) {
    if (toolbar != null) {
        for (int i = 0; i < toolbar.getChildCount(); i++) {
            final View view = toolbar.getChildAt(i);
            if (view instanceof ActionMenuView) {
                final ActionMenuView actionMenuView = (ActionMenuView) view;
                // view children are accessible only after layout-ing
                actionMenuView.post(new Runnable() {
                    @Override
                    public void run() {
                        for (int j = 0; j < actionMenuView.getChildCount(); j++) {
                            final View innerView = actionMenuView.getChildAt(j);
                            if (innerView instanceof ActionMenuItemView) {
                                final ActionMenuItemView itemView = (ActionMenuItemView) innerView;
                                if (resId == itemView.getId()) {
                                    itemView.setTextColor(ContextCompat.getColor(toolbar.getContext(), color));
                                }
                            }
                        }
                    }
                });
            }
        }
    }
}

通过这样做，你会失去背景选择器的效果，所以下面的代码将一个自定义的背景选择器应用到所有菜单项的子项上。

public static void setToolbarMenuItemsBackgroundSelector(final Context context,
                                                         final Toolbar toolbar) {
    if (toolbar != null) {
        for (int i = 0; i < toolbar.getChildCount(); i++) {
            final View view = toolbar.getChildAt(i);
            if (view instanceof ImageButton) {
                // left toolbar icon (navigation, hamburger, ...)
                UiHelper.setViewBackgroundSelector(context, view);
            } else if (view instanceof ActionMenuView) {
                final ActionMenuView actionMenuView = (ActionMenuView) view;

                // view children are accessible only after layout-ing
                actionMenuView.post(new Runnable() {
                    @Override
                    public void run() {
                        for (int j = 0; j < actionMenuView.getChildCount(); j++) {
                            final View innerView = actionMenuView.getChildAt(j);
                            if (innerView instanceof ActionMenuItemView) {
                                // text item views
                                final ActionMenuItemView itemView = (ActionMenuItemView) innerView;
                                UiHelper.setViewBackgroundSelector(context, itemView);

                                // icon item views
                                for (int k = 0; k < itemView.getCompoundDrawables().length; k++) {
                                    if (itemView.getCompoundDrawables()[k] != null) {
                                        UiHelper.setViewBackgroundSelector(context, itemView);
                                    }
                                }
                            }
                        }
                    }
                });
            }
        }
    }
}

下面是helper函数:

public static void setViewBackgroundSelector(@NonNull Context context, @NonNull View itemView) {
    int[] attrs = new int[]{R.attr.selectableItemBackgroundBorderless};
    TypedArray ta = context.obtainStyledAttributes(attrs);
    Drawable drawable = ta.getDrawable(0);
    ta.recycle();

    ViewCompat.setBackground(itemView, drawable);
}

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"。

最简单的方法为单个工具栏定制菜单颜色，而不是为AppTheme

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay.MenuBlue">
        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"/>
    </android.support.design.widget.AppBarLayout>

xml上常用的工具栏

<style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar"/>

自定义工具栏样式

<style name="AppTheme.AppBarOverlay.MenuBlue">
    <item name="actionMenuTextColor">@color/blue</item>
</style>

主题中的一句话:)

<item name="android:actionMenuTextColor">@color/your_color</item>

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。

添加textColor如下所示

<style name="MyTheme.PopupOverlay" parent="ThemeOverlay.AppCompat.Light">
    <item name="android:textColor">@color/radio_color_gray</item>
</style>

并在xml文件中的工具栏中使用它

<androidx.appcompat.widget.Toolbar
     android:id="@+id/toolbar"
     android:layout_width="match_parent"
     android:layout_height="?attr/actionBarSize"
     app:popupTheme="@style/MyTheme.PopupOverlay" />