Android menuInflater在OnCreateOptions菜单中创建菜单不工作

我已经使用MenuFlater在活动的OnCreateOptions菜单方法中创建了一个菜单。我使用它在日历的工具栏上显示箭头，以便用户可以转到上个月或下个月。但由于某些原因，箭头没有显示出来 请找个人帮忙

每月活动：

private MonthGridFragment monthGridFragment;

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu_calendar_grid, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.action_previous:
            monthGridFragment.loadLastMonth();
            return true;
        case R.id.action_next:
            monthGridFragment.loadNextMonth();
            return true;
        case R.id.all_events:
            monthGridFragment.showAllEvents();
            return true;
    }
    return super.onOptionsItemSelected(item);
}

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

    monthGridFragment = new MonthGridFragment();
    getSupportFragmentManager().beginTransaction()
            .add(R.id.activity_calendar_grid_container, monthGridFragment)
            .commit();
}

菜单\u日历\u grid.xml

<item
    android:id="@+id/action_previous"
    android:title="@string/prev_month"
    android:orderInCategory="100"
    app:showAsAction="ifRoom"
    android:icon="@drawable/arrow_previous" />
<item
    android:id="@+id/action_next"
    android:title="@string/next_month"
    android:orderInCategory="100"
    app:showAsAction="ifRoom"
    android:icon="@drawable/arrow_next" />
<item
    android:id="@+id/all_events"
    android:title="@string/view_all_events"
    android:orderInCategory="101"
    app:showAsAction="never"
    android:icon="@android:drawable/ic_menu_view" />

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
  tools:ignore="MergeRootFrame">

<android.support.v7.widget.Toolbar
    android:id="@+id/myActivity_toolbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"/>

<android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/pager"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:id="@+id/calendar_grid_layout">

<include layout="@layout/calendar_grid_header" />


<GridView
    android:paddingTop="1dp"
    android:gravity="center"
    android:layout_gravity="center"
    android:layout_margin="0dp"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/calendar_grid_view"
    android:numColumns="7"
    android:stretchMode="columnWidth"
    android:background="@color/white_gray"
    android:horizontalSpacing="1dp"
    android:verticalSpacing="1dp" />

活动\日历\网格.xml

<item
    android:id="@+id/action_previous"
    android:title="@string/prev_month"
    android:orderInCategory="100"
    app:showAsAction="ifRoom"
    android:icon="@drawable/arrow_previous" />
<item
    android:id="@+id/action_next"
    android:title="@string/next_month"
    android:orderInCategory="100"
    app:showAsAction="ifRoom"
    android:icon="@drawable/arrow_next" />
<item
    android:id="@+id/all_events"
    android:title="@string/view_all_events"
    android:orderInCategory="101"
    app:showAsAction="never"
    android:icon="@android:drawable/ic_menu_view" />

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
  tools:ignore="MergeRootFrame">

<android.support.v7.widget.Toolbar
    android:id="@+id/myActivity_toolbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"/>

<android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/pager"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:id="@+id/calendar_grid_layout">

<include layout="@layout/calendar_grid_header" />


<GridView
    android:paddingTop="1dp"
    android:gravity="center"
    android:layout_gravity="center"
    android:layout_margin="0dp"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/calendar_grid_view"
    android:numColumns="7"
    android:stretchMode="columnWidth"
    android:background="@color/white_gray"
    android:horizontalSpacing="1dp"
    android:verticalSpacing="1dp" />

fragment\u calendar\u grid.xml

<item
    android:id="@+id/action_previous"
    android:title="@string/prev_month"
    android:orderInCategory="100"
    app:showAsAction="ifRoom"
    android:icon="@drawable/arrow_previous" />
<item
    android:id="@+id/action_next"
    android:title="@string/next_month"
    android:orderInCategory="100"
    app:showAsAction="ifRoom"
    android:icon="@drawable/arrow_next" />
<item
    android:id="@+id/all_events"
    android:title="@string/view_all_events"
    android:orderInCategory="101"
    app:showAsAction="never"
    android:icon="@android:drawable/ic_menu_view" />

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
  tools:ignore="MergeRootFrame">

<android.support.v7.widget.Toolbar
    android:id="@+id/myActivity_toolbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"/>

<android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/pager"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:id="@+id/calendar_grid_layout">

<include layout="@layout/calendar_grid_header" />


<GridView
    android:paddingTop="1dp"
    android:gravity="center"
    android:layout_gravity="center"
    android:layout_margin="0dp"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/calendar_grid_view"
    android:numColumns="7"
    android:stretchMode="columnWidth"
    android:background="@color/white_gray"
    android:horizontalSpacing="1dp"
    android:verticalSpacing="1dp" />

---

在

onCreate

方法中创建工具栏：

Toolbar toolbar = (Toolbar) findViewById(R.id.myActivity_toolbar);
setActionBar(toolbar);

因此，在布局中添加视图：

<Toolbar
    android:id="@+id/myActivity_toolbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"/>

UPD:

---

您必须使用支持库或标准库中的

工具栏

。如果

MonthGridActivity

扩展自

Activity

，请在布局中使用

工具栏

（而不是

android.support.v7.widget.Toolbar

）。否则，

MonthGridActivity

必须从

AppCompatActivity

扩展得到一个错误提示；错误：（51,29）错误：不兼容的类型：android.widget.Toolbar无法转换为android.support.v7.widget.Toolbar请附加布局文件BTW：我认为在左右箭头中使用相同的android:orderInCategory值是不好的做法。另外，应用程序：showAsAction意味着如果没有足够的空间，您的箭头可能会被隐藏。