Android之上下文菜单

上下文菜单经常用到ListView或者是GridView中。

①浮动的上下文菜单，类似对话框的（对话框应该有至少一个按钮，但是上下文菜单没有按钮），只有长按ListView的item会弹出上下文菜单。

新建工程android_ContextMenu中activity_main.xml添加一个ListView控件

<RelativeLayout 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"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="com.example.android_contextmenu.MainActivity" >     <ListView        android:id="@+id/listView1"        android:layout_width="match_parent"        android:layout_height="match_parent"        android:layout_alignParentLeft="true"        android:layout_alignParentTop="true" >    </ListView>    </RelativeLayout>

在string.xml中添加

<string name="edit">编辑</string>    <string name="share">分享</string>    <string name="delete">删除</string>

在main.xml中添加

 <item        android:id="@+id/edit"        android:orderInCategory="100"        android:title="@string/edit"        app:showAsAction="never"/>           <item        android:id="@+id/share"        android:orderInCategory="100"        android:title="@string/share"        app:showAsAction="never"/>             <item        android:id="@+id/delete"        android:orderInCategory="100"        android:title="@string/delete"        app:showAsAction="never"/>

在MainActivity.java中

package com.example.android_contextmenu;import java.util.ArrayList;import java.util.List;import android.support.v7.app.ActionBarActivity;import android.os.Bundle;import android.view.ContextMenu;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.view.ContextMenu.ContextMenuInfo;import android.widget.AdapterView.AdapterContextMenuInfo;import android.widget.ArrayAdapter;import android.widget.ListView;import android.widget.Toast;public class MainActivity extends ActionBarActivity {private ListView listView;private ArrayAdapter<String> adapter;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);listView=(ListView) this.findViewById(R.id.listView1);adapter=new ArrayAdapter<String>(this, android.R.layout.simple_expandable_list_item_1,getData());listView.setAdapter(adapter);//加载适配器registerForContextMenu(listView);}public List<String> getData(){ List<String> list=new ArrayList<String>(); for(int i=0;i<10;i++){ list.add("CCNU"+i); }return list; }/** * 添加上下文菜单的重新方法 */@Overridepublic void onCreateContextMenu(ContextMenu menu, View v,ContextMenuInfo menuInfo) {// TODO Auto-generated method stubgetMenuInflater().inflate(R.menu.main, menu);super.onCreateContextMenu(menu, v, menuInfo);}/** * 添加点击事件 */@Overridepublic boolean onContextItemSelected(MenuItem item) {// TODO Auto-generated method stubAdapterContextMenuInfo info=(AdapterContextMenuInfo) item.getMenuInfo();switch (item.getItemId()) {case R.id.edit:String value=adapter.getItem(info.position);//拿到要编辑的条目的idToast.makeText(MainActivity.this, "----edit-->>"+value, 1).show();break;case R.id.share:break;case R.id.delete:break;}return super.onContextItemSelected(item);}//@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;//}@Overridepublic 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();if (id == R.id.action_settings) {return true;}return super.onOptionsItemSelected(item);}}

长按ListView中的条目效果如下