无法解决Android Studio中的符号“菜单"错误

我正在从 Github 上提供的.

I'm learning Android Development for Beginners from Udacity and have completed making an app named Court Counter in which I wrote code for an XML (activity_main.xml) and some code for Java (MainActivity.java) file as some of the code was provided by the Udacity team on Github.

但是，当我单击"Build APK"时，我从Java文件中都得到了两个错误:

But when I click on 'Build APK' I get two errors both from the Java file:

1. 无法解析以下代码中的符号菜单":-

1. Cannot resolve symbol 'menu' in the following code:-

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

1. 无法解析符号"action_settings":-

1. Cannot resolve symbol 'action_settings':-

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}

我不知道执行这些代码块时会发生什么，但是我想在手机上运行该应用程序！

I don't know what happens when these block of code are executed but I want to run the app on my phone!