安卓--ListView

实验目的：

学习使用ListView

实验要求：

实现一个列表，其中显示班级学号姓名，提供添加功能，如需要删去某一项，长按该项，通过弹出菜单显示删除功能。

 package com.flyuz.app3;

 import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
 import android.view.View;
 import android.view.MenuItem ;
 import android.widget.Button;
 import android.widget.ListView;
 import android.widget.ArrayAdapter;
 import android.widget.EditText;
 import android.widget.PopupMenu;
 import android.widget.AdapterView;
 import java.util.List;
 import java.util.ArrayList;

 public class MainActivity extends AppCompatActivity {
     private Button bt_add;
     private ListView lv;

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

     private void init() {
         bt_add = (Button) findViewById(R.id.bt_add);
         lv = (ListView) findViewById(R.id.lv);
         List<String> list = new ArrayList<String>();
         list.add("班级" + "                    " + "学号" + "                    " + "姓名");
         list.add("se1" + "             " + "2016012884" + "                 " + "张三");
         ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, list);
         lv.setAdapter(adapter);

         //设置事件
         bt_add.setOnClickListener(new View.OnClickListener() {
             public void onClick(View v) {
                 EditText et_class = (EditText) findViewById(R.id.et_class);
                 EditText et_number = (EditText) findViewById(R.id.et_number);
                 EditText et_name = (EditText) findViewById(R.id.et_name);
                 String str_class = et_class.getText().toString();
                 String str_number = et_number.getText().toString();
                 String str_name = et_name.getText().toString();

                 ArrayAdapter add_adp = (ArrayAdapter) lv.getAdapter();
                 add_adp.add(str_class + "             " + str_number + "             " + str_name);
             }
         });
         lv.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
             @Override
             public boolean onItemLongClick(AdapterView<?> parent, View view, final int position, long id) {
                 if (id > 0) {
                     PopupMenu popup = new PopupMenu(MainActivity.this, view);
                     popup.getMenuInflater().inflate(R.menu.menu, popup.getMenu());
                     popup.show();
                     popup.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
                         @Override
                         public boolean onMenuItemClick(MenuItem item) {
                             switch (item.getItemId()) {
                                 case R.id.menu_del:
                                     ArrayAdapter temp_adp = (ArrayAdapter) lv.getAdapter();
                                     temp_adp.remove(temp_adp.getItem(position));
                                     return true;
                                 default:
                                     return false;
                             }
                         }
                     });
                 }
                 return true;
             }
         });
     }
 }

MainActivity

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical"
     tools:context="com.flyuz.app3.MainActivity">

     <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="200dp"
         android:gravity="center"
         android:orientation="vertical">

         <LinearLayout
             android:layout_width="match_parent"
             android:layout_height="50dp"
             android:gravity="center"
             android:orientation="horizontal">

             <TextView
                 android:layout_width="50dp"
                 android:layout_height="40dp"
                 android:gravity="center"
                 android:text="班级:" />

             <EditText
                 android:id="@+id/et_class"
                 android:layout_width="150dp"
                 android:layout_height="40dp" />
         </LinearLayout>

         <LinearLayout
             android:layout_width="match_parent"
             android:layout_height="50dp"
             android:gravity="center"
             android:orientation="horizontal">

             <TextView
                 android:layout_width="50dp"
                 android:layout_height="40dp"
                 android:gravity="center"
                 android:text="学号:" />

             <EditText
                 android:id="@+id/et_number"
                 android:layout_width="150dp"
                 android:layout_height="40dp" />
         </LinearLayout>

         <LinearLayout
             android:layout_width="match_parent"
             android:layout_height="50dp"
             android:gravity="center"
             android:orientation="horizontal">

             <TextView
                 android:layout_width="50dp"
                 android:layout_height="40dp"
                 android:gravity="center"
                 android:text="姓名:" />

             <EditText
                 android:id="@+id/et_name"
                 android:layout_width="150dp"
                 android:layout_height="40dp" />
         </LinearLayout>

         <Button
             android:id="@+id/bt_add"
             android:layout_width="180dp"
             android:layout_height="40dp"
             android:text="添加" />

     </LinearLayout>
     <ListView
         android:id="@+id/lv"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:longClickable="true" />

 </LinearLayout>

layout\activity_main.xml

 <?xml version="1.0" encoding="utf-8"?>
 <menu xmlns:android="http://schemas.android.com/apk/res/android">
     <item
         android:id="@+id/menu_del"
         android:title="删除">
     </item>
 </menu>

menu\menu.xml