Android随笔---menu菜单的使用

1.在res资源下，创建Resource Directory资源
2.创建menu.xml
3.创建菜单选项
4.重写创建菜单的Java代码
5.重写菜单的单个选项的操作函数

package com.example.firstapplication;

import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

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

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

    @Override
    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
        switch (item.getItemId()){
            case R.id.add:
                Toast.makeText(this,"you check add",Toast.LENGTH_SHORT).show();
                break;
            case R.id.delete:
                Toast.makeText(this,"you check delete",Toast.LENGTH_SHORT).show();
                break;
            default:
        }
        return true;
    }
}