我已经在AndroidManifest中注册过了
而且也没有调用MenuItemSelected这个方法,我的代码主要是为了实现,点击MainActivity中的菜单项跳转到另外一个界面。//MainActivity
package com.example.exp10_1;import java.lang.reflect.Method;
import android.app.Activity;
import android.app.ListActivity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.NavUtils;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;public class MainActivity extends Activity { @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if(NavUtils.getParentActivityName(MainActivity.this)!=null){
getActionBar().setDisplayHomeAsUpEnabled(false);
} } @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);
if(menu.getClass().getSimpleName().equals("MenuBuilder")) {
try {
Class<?> clzz = menu.getClass(); //获取menu运行时所有对应的类
Method m = clzz.getDeclaredMethod("setOptionalIconsVisible", Boolean.TYPE);
m.setAccessible(true); //设置setOptionalIconVisible的权限
m.invoke(menu,true); //调用该方法,并将该方法的参数设置为true
}catch(Exception e) {
e.printStackTrace();
}
}
return true;
} @Override
public 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.
TextView tv =(TextView) findViewById(R.id.tv);
switch (item.getItemId()) { //得到被点击的item的itemId
case R.id.groupchat: //这里的Id就是布局文件中定义的Id,在用R.id.XXX的方法获取出来
tv.setText("发起群聊");
break;
case R.id.addfriend:{
Intent intent = new Intent(MainActivity.this,ListActivity.class); //创建Intent对象
startActivity(intent);
break;
}
case R.id.scan:
tv.setText("扫一扫");
break;
case R.id.help:
tv.setText("帮助与反馈");
break;
}
return true;
}
}//ListActivity
package com.example.exp10_1;import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.app.NavUtils;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ListView;
import android.widget.SimpleAdapter;public class ListActivity extends Activity{
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.listview);
getActionBar().setDisplayHomeAsUpEnabled(true);
String[] titles=new String[]{"雷达加朋友","面对面建群","扫一扫","手机联系人","公众号"};
int[] images=new int[]{R.drawable.ray,R.drawable.creatgroupchat,R.drawable.scanning,R.drawable.link,R.drawable.publicnumber};
String text[]=new String[]{"添加身边的朋友","与身边的朋友进入同一个群聊","扫描二维码名片","添加或邀请通讯录中的朋友","获取更多资讯和服务"};
ListView lv=(ListView)findViewById(R.id.lv);
List<Map<String,Object>>listItems=new ArrayList<Map<String,Object>>();
for(int i=0;i<images.length;i++){
Map<String,Object>map=new HashMap<String,Object>();
map.put("image",images[i]);
map.put("title", titles[i]);
map.put("text", text[i]);
listItems.add(map);
}
SimpleAdapter adapter=new SimpleAdapter(this,listItems,R.layout.listitem,new String[]{"image","title","text"},
new int[]{R.id.img,R.id.tv1,R.id.tv2});
lv.setAdapter(adapter);
if(NavUtils.getParentActivityName(ListActivity.this)!=null) {
getActionBar().setDisplayHomeAsUpEnabled(true); //显示向左的箭头图标
}
} @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;
} @Override
public 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 == android.R.id.home) {//判断是否单击左侧的箭头图标
if(NavUtils.getParentActivityName(ListActivity.this)!=null){
//导航至父Activity
NavUtils.navigateUpFromSameTask(ListActivity.this);
}
return true;
}else{
return super.onOptionsItemSelected(item);
}
}
}//布局文件activity_main.xml
<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.exp10_1.MainActivity" > <TextView
android:id="@+id/tv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:textSize="20sp"
android:text="@string/hello_world" /></RelativeLayout>//listview.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="match_parent"
android:orientation="vertical" >
<EditText
android:id="@+id/et"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:hint="微信号/QQ号/手机号"
android:drawableLeft="@drawable/searching"
/>
<ListView
android:id="@+id/lv"
android:layout_height="match_parent"
android:layout_width="fill_parent"
android:scrollbarAlwaysDrawVerticalTrack="false"
android:footerDividersEnabled="false"
android:divider="#A9A9A9"
android:dividerHeight="1.5dp"
></ListView></LinearLayout>//AndroidManifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.exp10_1"
android:versionCode="1"
android:versionName="1.0" > <uses-sdk
android:minSdkVersion="14"
android:targetSdkVersion="21" /> <application
android:allowBackup="true"
android:icon="@drawable/wechat"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="微信" >
<intent-filter>
<action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity> <activity
android:name=".ListActivity"
android:label="添加朋友" >
<meta-data android:name="android.support.PARENT_ACTIVITY"
android:value=".MainActivity"/>
</activity>
</application></manifest>
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