添加菜单

1.线性布局 添加按钮

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
 tools:context="com.example.administrator.android.MainActivity"
android:orientation="vertical">

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="按钮"
        android:id="@+id/bt_1"/>
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="上下文菜单按钮"
        android:id="@+id/bt_2"/>
</LinearLayout>

注意：

1.android:orientation="vertical" 在线性布局里必须添加

2.添加程序运行java代码

package com.example.administrator.android;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.ContextMenu;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.SubMenu;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    Button bt_1;
    Button bt_2;


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

        bt_1 = (Button)findViewById(R.id.bt_1);
        bt_2 = (Button)findViewById(R.id.bt_2);


        //给组件添加上下文菜单
        bt_2.setOnCreateContextMenuListener(this);
//        //添加长按监听器
//        bt_2.setOnLongClickListener(new View.OnLongClickListener() {
//            @Override
//            public boolean onLongClick(View v) {
//                Toast.makeText(MainActivity.this, "按钮被长按", Toast.LENGTH_SHORT).show();
//                return true;//后面不再处理
//            }
//        });
        //点击
        bt_1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Toast.makeText(MainActivity.this, "按钮被点击", Toast.LENGTH_SHORT).show();
            }
        });
        //长按
        bt_1.setOnLongClickListener(new View.OnLongClickListener() {
            @Override
            public boolean onLongClick(View v) {

                Toast.makeText(MainActivity.this, "按钮被长按", Toast.LENGTH_SHORT).show();
                //事件是否已经被消费
                return true;
            }
        });
    }
    //重写创建上下文菜单的方法
    @Override
    public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
        super.onCreateContextMenu(menu, v, menuInfo);
        //代码模式（java）
        menu.add(1, 0, 1, "字体大小");
        menu.add(1,1,2,"背景颜色");
        //添加子菜单
        SubMenu sm = menu.addSubMenu(1, 2, 3, "子菜单");
        sm.add(2,21,0,"子菜单1");
        sm.add(2,22,1,"子菜单2");
        //加载文件
        MenuInflater m = getMenuInflater();
        m.inflate(R.menu.test3_menu,menu);
    }

    @Override
    public boolean onContextItemSelected(MenuItem item) {

        Toast.makeText(MainActivity.this, "上下文菜单的标题:"+item.getTitle(), Toast.LENGTH_SHORT).show();

        return super.onContextItemSelected(item);
    }

    //给activity 添加选项菜单
    //重写
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
//        //添加菜单
//        menu.add(1,1,0,"添加");
//        menu.add(1,2,2,"修改");
//        menu.add(1,3,1,"删除");

        //加载菜单文件方式
        //1-获得菜单加载器
        MenuInflater m = getMenuInflater();

        //2-加载菜单文件 1)菜单文件 2）当前菜单
        m.inflate(R.menu.test3_menu,menu);

        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        Toast.makeText(MainActivity.this, "菜单项的id="+item.getItemId()
                +"菜单项的Title"+item.getTitle(), Toast.LENGTH_SHORT).show();
        if (item.getItemId()==R.id.me_1)
        {
            Toast.makeText(MainActivity.this, "删除被执行", Toast.LENGTH_SHORT).show();
        }
        else if (item.getItemId()==R.id.me_2)
        {
            Toast.makeText(MainActivity.this, "修改被执行", Toast.LENGTH_SHORT).show();
        }
        return super.onOptionsItemSelected(item);
    }
}

3。添加目录代码程序

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:id="@+id/me_1" android:title="删除"/>
    <item android:id="@+id/me_2" android:title="修改"/>
</menu>