Android菜单使用之ContextMenu（上下文菜单）

       在Android应用中，ContextMenu的使用十分普遍，尤其与Listview搭配使用的情况很多。长按一个控件或Listview的一项，会弹出ContextMenu。

     一般通过以下三个方法实现ContextMenu的使用。

    1.为控件注册ContextMenu

public void registerForContextMenu (View view)

    2.重写创建ContextMenu方法

public void onCreateContextMenu (ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo)

 

    3.重写选择ContextMenu方法

public boolean onContextItemSelected(MenuItem item)

其他的一些方法可参见官方API：http://developer.android.com/reference/android/view/ContextMenu.html

以下是个人写的一个Listview使用ContextMenu的小例子，功能非常简单。点击Listview的某一项弹出ContextMenu，选择删除选项，删除Listview的当前项。

Listview的一行布局item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="3dp"
android:orientation="horizontal" >

<ImageView
android:id="@+id/imageView1"
android:layout_width="50dp"
android:layout_height="50dp"
android:src="@drawable/find" />

<LinearLayout
android:layout_marginLeft="5dp"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >

<TextView
android:id="@+id/tv_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="20sp"
android:text="姓名" />

<TextView
android:layout_marginTop="5dp"
android:id="@+id/tv_phone"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="1500000000" />
</LinearLayout>

</LinearLayout>

主界面

MainActivity.java

/**
*
* @author ElaineWong
*
*/
public class MainActivity extends ListActivity {
private Context mContext;

private ListView lv_contact;

private SimpleAdapter sa_contact;
private List<HashMap<String,Object>> contactList;

private final int MENU_DELETE=0,MENU_EDIT=1;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mContext=this;

initView();
initData();
}

private void initView(){
lv_contact=getListView();
}

private void initData(){
contactList=new ArrayList<HashMap<String,Object>>();

for(int i=0;i<20;i++){
HashMap<String,Object> map=new HashMap<String, Object>();
map.put("name", "姓名"+i);
map.put("phone", "15312001080");
map.put("icon",R.drawable.find);

contactList.add(map);
}

String[] from={"name","phone","icon"};
int[] to={R.id.tv_name,R.id.tv_phone,R.id.imageView1};
sa_contact=new SimpleAdapter(mContext, contactList, R.layout.item, from, to);
lv_contact.setAdapter(sa_contact);

//注册ContextMenu
registerForContextMenu(lv_contact);
}

//创建ContextMenu方法
@Override
public void onCreateContextMenu(ContextMenu menu, View v,
ContextMenuInfo menuInfo) {
try {
AdapterContextMenuInfo mMenuInfo = (AdapterContextMenuInfo) menuInfo;
menu.setHeaderTitle(contactList.get(mMenuInfo.position).get("name").toString());
menu.setHeaderIcon(R.drawable.find);
} catch (Exception e) {
return;
}
int groupId=0;
menu.add(groupId,MENU_DELETE, 0, "删除联系人");
menu.add(groupId,MENU_EDIT, 1, "编辑联系人");

super.onCreateContextMenu(menu, v, menuInfo);
}

//点击ContextMenu处理方法
@Override
public boolean onContextItemSelected(MenuItem item) {
AdapterContextMenuInfo itemInfo = (AdapterContextMenuInfo) item.getMenuInfo();
switch (item.getItemId()) {
case MENU_DELETE:
Toast.makeText(mContext,item.getTitle()+":"+contactList.get(itemInfo.position).get("name").toString(), Toast.LENGTH_LONG).show();
contactList.remove(itemInfo.position);
sa_contact.notifyDataSetChanged();
break;
case MENU_EDIT:
Toast.makeText(mContext,item.getTitle()+":"+contactList.get(itemInfo.position).get("name").toString(), Toast.LENGTH_LONG).show();
break;
default:
break;
}
return super.onContextItemSelected(item);
}

}

效果图



长按一项弹出ContextMenu



选择删除某一项之后