如何在Android的ActionMode类中添加自己的函数？

public class MyActionModeCallback implements ActionMode.Callback {
    // 实现回调方法
}

@Override
public boolean onCreateActionMode(ActionMode mode, Menu menu) {
    // 创建菜单
    getMenuInflater().inflate(R.menu.my_action_mode_menu, menu);
    return true;
}

<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:id="@+id/action_my_function"
        android:title="My Function"
        android:icon="@drawable/ic_my_function"
        android:showAsAction="always" />
</menu>

@Override
public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
    int itemId = item.getItemId();
    switch (itemId) {
        case R.id.action_my_function:
            // 执行自己的函数逻辑
            performMyFunction();
            mode.finish(); // 结束ActionMode
            return true;
        default:
            return false;
    }
}

public boolean onCreateOptionsMenu(Menu menu) {
    // ...
    getMenuInflater().inflate(R.menu.main_menu, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    int itemId = item.getItemId();
    if (itemId == R.id.action_start_action_mode) {
        startActionMode(new MyActionModeCallback());
        return true;
    }
    return super.onOptionsItemSelected(item);
}