菜单（三）二级菜单和标题栏菜单

package com.example.menu2;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;

public class MainActivity extends Activity {

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

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

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		switch (item.getItemId()) {
		case R.id.create:
			Toast.makeText(MainActivity.this, "创立文件", Toast.LENGTH_SHORT).show();
			break;
		case R.id.open:
			Intent intent = new Intent(MainActivity.this, NextActivity.class);
			item.setIntent(intent);
//			Toast.makeText(MainActivity.this, "打开文件", Toast.LENGTH_SHORT).show();
			break;
		case R.id.load:
			Toast.makeText(MainActivity.this, "加载", Toast.LENGTH_SHORT).show();
			break;
		case R.id.save:
			Toast.makeText(MainActivity.this, "保留", Toast.LENGTH_SHORT).show();
			break;
		default:
			break;
		}
		return super.onOptionsItemSelected(item);
	}
}
package com.example.menu2;

import android.app.Act