通过xml文件定义菜单

通过xml文件定义菜单，并在Activity中引用菜单资源，并为菜单项绑定监听器，实现为TextView设置各种属性。

上下文菜单的xml资源文件,context.xml:

<menu xmlns:android="http://schemas.android.com/apk/res/android"        >    <group         android:checkableBehavior="single"        >        <item android:id="@+id/red"            android:title="@string/red_title"            android:alphabeticShortcut="r"            ></item>        <item android:id="@+id/green"            android:title="@string/green_title"            android:alphabeticShortcut="g"            ></item>        <item android:id="@+id/blue"            android:title="@string/blue_title"            android:alphabeticShortcut="b"            ></item>    </group>    </menu>

菜单项资源文件，my_menu.xml:

<?xml version="1.0" encoding="utf-8"?><menu xmlns:android="http://schemas.android.com/apk/res/android" >        <item        android:title="@string/font_size"        android:icon="@drawable/font"        >        <menu>     <!-- 定义一组菜单选项 -->            <group                 android:checkableBehavior="single"                >                <item                     android:id="@+id/font_10"                    android:title="@string/font_10"                    ></item>                <item                     android:id="@+id/font_12"                    android:title="@string/font_12"                    ></item>                <item                     android:id="@+id/font_14"                    android:title="@string/font_14"                    ></item>                <item                     android:id="@+id/font_16"                    android:title="@string/font_16"                    ></item>                <item                     android:id="@+id/font_18"                    android:title="@string/font_18"                    ></item>            </group>        </menu>    </item>    <!-- 定义一个普通菜单项 --><item     android:id="@+id/plain_item"    android:title="@string/plain_item"    /><item     android:id="@+id/font_color"    android:title="@string/font_color"    android:icon="@drawable/color"        >    <menu>        <!-- 定义一组允许复选的菜单项 -->        <group android:checkableBehavior="single">        <item             android:id="@+id/red"            android:title="@string/red_title"            />        <item             android:id="@+id/green"            android:title="@string/green_title"            />        <item             android:id="@id/blue"            android:title="@string/blue_title"            />         </group>    </menu></item></menu>

Activity代码：

package com.example.menurestest;import android.os.Bundle;public class MenuResTest extends Activity {private TextView txt;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_menu_res_test);        txt=(TextView)findViewById(R.id.txt);        //为文本框注册上下文菜单        registerForContextMenu(txt);    }    @Override    public boolean onCreateOptionsMenu(Menu menu) {        //添加菜单资源的方法一    getMenuInflater().inflate(R.menu.my_menu, menu);        return true;    }    //每次 创建上下文菜单时都会触发该方法@Overridepublic void onCreateContextMenu(ContextMenu menu, View v,ContextMenuInfo menuInfo) {// TODO Auto-generated method stub//添加菜单资源的方法二MenuInflater inflater=new MenuInflater(this);inflater.inflate(R.menu.context, menu);menu.setHeaderIcon(R.drawable.tools);menu.setHeaderTitle("请选择背景色");menu.setGroupCheckable(1, true, true);}//上下文菜单项被单击时触发该方法    @Overridepublic boolean onContextItemSelected(MenuItem item) {// TODO Auto-generated method stub    switch(item.getItemId()){    case R.id.red:    item.setChecked(true);    txt.setBackgroundColor(Color.RED);    break;    case R.id.green:    item.setChecked(true);    txt.setBackgroundColor(Color.GREEN);    break;    case R.id.blue:    item.setChecked(true);    txt.setBackgroundResource(Color.BLUE);    break;    }return super.onContextItemSelected(item);}    @Overridepublic boolean onOptionsItemSelected(MenuItem item) {// TODO Auto-generated method stub    switch(item.getItemId()){    case R.id.font_10:    item.setChecked(true);    txt.setTextSize(10*2);    break;    case R.id.font_12:    item.setChecked(true);    txt.setTextSize(12*2);    break;    case R.id.font_14:    item.setChecked(true);    txt.setTextSize(14*2);    break;    case R.id.font_16:    item.setChecked(true);    txt.setTextSize(16*2);    break;    case R.id.font_18:    txt.setTextSize(18*2);    item.setChecked(true);item.setChecked(true);    break;    case R.id.red:    txt.setTextColor(Color.RED);    item.setChecked(true);    break;    case R.id.blue:    txt.setTextColor(Color.BLUE);    item.setChecked(true);    break;    case R.id.green:    item.setChecked(true);    txt.setTextColor(R.color.green);    break;    case R.id.plain_item:    Toast.makeText(MenuResTest.this, "您单击了普通菜单", Toast.LENGTH_SHORT).show();    break;    }return super.onOptionsItemSelected(item);}    }

运行结果：