Android上下文菜单ContextMenu

ContextMenu是一种悬浮于主界面上的菜单。当注册到一个View对象上时，默认情况下可以长按View对象约2秒钟呼出上下文菜单。

Context menus do not support item shortcuts and item icons：不支持快捷键和显示图标。

To show a context menu on long click, most clients will want to call registerForContextMenu(View) and override onCreateContextMenu(ContextMenu, View, ContextMenu.ContextMenuInfo).

实现步骤： 1、定义一个View对象，并给它注册上下文菜单 ：registerForContextMenu(View) 2、重写回调函数： onCreateContextMenu(...) 3、响应点击事件： onContextItemSelected(MenuItem item)   main.xml

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

     android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:orientation="vertical"

>  <TextView    android:id="@+id/myTextView"    android:textSize="20sp"    android:layout_width="fill_parent"    android:layout_height="wrap_content"    android:text="hello"    />    </LinearLayout>

下面是 .java

 

package com.example.menucontext;

 

import android.app.Activity;import android.os.Bundle;import android.view.ContextMenu;import android.view.Menu;import android.view.MenuItem;import android.view.ContextMenu.ContextMenuInfo;import android.view.View;

 

import android.widget.TextView;import android.util.Log;public class ContextMenuActivity extends Activity {        private static final int C_MENU_NEW = 0;    private static final int C_MENU_OPEN =1;      MenuItem contextmenu_item_new=null;    MenuItem contextmenu_item_open=null;    /** Called when the activity is first created. */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);           TextView tv=new TextView(this);        tv.setText("上下文菜单的载体");

        //将上文定义的TextView注册上下文菜单        registerForContextMenu(tv);        setContentView(tv);           }               //上下文菜单，本例会通过长按条目激活上下文菜单    @Override    public void onCreateContextMenu(ContextMenu menu, View view,             ContextMenuInfo menuInfo) {        menu.setHeaderTitle("welsh");        //添加菜单项       contextmenu_item_new=menu.add(0, C_MENU_NEW, 0, "新建");        contextmenu_item_open=menu.add(0,C_MENU_OPEN, 0, "打开");            }        //菜单单击响应    @Override    public boolean onContextItemSelected(MenuItem item){        //获取当前被选择的菜单项的信息          switch(item.getItemId()){        case C_MENU_NEW:            //在这里添加处理代码                        break;        case C_MENU_OPEN:            //在这里添加处理代码                        break;                  }        return true;    }    }

 

 结果图：

转载于:https://www.cnblogs.com/welsh-android-learning/archive/2012/08/05/2623585.html