逆境是成长必经的过程，能勇于接受逆境的人，生命就会日渐的茁壮。

本讲内容：GridView和ActivityGroup实现的Tab分页

一、ActivityGroup相关--getLocalActivityManager() 以及intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)用法

1、ActivityGroup中可以调用getLocalActivityManager（）方法获取LocalActityManager来管理Activity。

2、LocalActivityManager通过startActivity(Stringid, Intent intent)方法,可以与指定的Actiivty绑定，并且返回一个Window。LocalActivityManager可以同时管理多个Activity

3、Window可以通过getDecorView()方法，返回一个View,然后通过与指定容器的addView(View)方法,实现不同的效果

intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)如果在当前任务中，有要启动的Activity，那么把该Acitivity之前的所有Activity都关掉，并把此Activity置前以避免创建Activity的实例

示例一效果图：

       

下面是res/layout/activity_main.xml 布局文件：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent" ><!-- 动态显示界面 --><LinearLayoutandroid:id="@+id/body"android:layout_width="match_parent"android:layout_height="wrap_content"android:layout_above="@+id/gridView"android:layout_alignParentTop="true"android:orientation="vertical" ></LinearLayout><!-- 底部功能菜单栏 --><GridViewandroid:id="@+id/gridView"android:layout_width="match_parent"android:layout_height="wrap_content"android:layout_alignParentBottom="true"android:background="@drawable/navigationbardown"android:cacheColorHint="#00000000"android:gravity="center"android:listSelector="@android:color/transparent"android:verticalSpacing="0dp" /></RelativeLayout>

技巧 ：制作背景色：用PS 画条黑线（navigationbardown.png）即为黑色了

下面是ImageAdaper.java文件：

public class ImageAdapter extends BaseAdapter{//普通图片数组private int[] imgs={R.drawable.home, R.drawable.addrbook, R.drawable.longnormal};//高亮图片数组protected int[] imgsLight={R.drawable.home1, R.drawable.addrbook1, R.drawable.longhightlight};;private int selectItem;private Context context;  //图片适配器，里面有一个设置高亮的方法比较重要protected void setImageLih(int selectItem) {this.selectItem=selectItem;//界面刷新notifyDataSetChanged();}public ImageAdapter(Context context) {this.context = context;  }@Overridepublic int getCount() {return imgs.length;}@Overridepublic Object getItem(int position) {return imgs[position];}@Overridepublic long getItemId(int position) {return position;}@Overridepublic View getView(int position, View convertView, ViewGroup parent) {if(convertView==null){//产生ImageView 对象  convertView = new ImageView(context);}if(position==selectItem){convertView.setBackgroundResource(imgsLight[position]);}else{convertView.setBackgroundResource(imgs[position]);}return convertView;}}

下面是MainActivity.java主界面文件：

public class MainActivity extends ActivityGroup {// Tab标签private GridView gridView;// GridView 适配器private ImageAdapter adapter;// 装载Activity的容器private LinearLayout layout;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);initUI();}private void initUI() {adapter = new ImageAdapter(this);layout = (LinearLayout) findViewById(R.id.body);gridView = (GridView) findViewById(R.id.gridView);// 因为我们显示一行，列数等于数组的长度gridView.setNumColumns(adapter.getCount());gridView.setAdapter(adapter);startActivity(0);gridView.setOnItemClickListener(new OnItemClickListener() {@Overridepublic void onItemClick(AdapterView<?> Parent, View view,int position, long id) {// 点击设置高亮显示adapter.setImageLih(position);startActivity(position);}});}// 根据position跳转到不同的Activityprivate void startActivity(int position) {// 先清除容器里面的Viewlayout.removeAllViews();Intent intent = null;if (position == 0) {intent = new Intent(MainActivity.this, OneView.class);} else if (position == 1) {intent = new Intent(MainActivity.this, TwoView.class);} else if (position == 2) {intent = new Intent(MainActivity.this, ThreeView.class);}intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);// 将Activity转换成ViewView view = getLocalActivityManager().startActivity("intent", intent).getDecorView();LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,LinearLayout.LayoutParams.MATCH_PARENT);// 将Activity转换成的View添加到容器layout.addView(view, layoutParams);}}

使用view的removeAllViews()方法清除不需要的view，使用addView(Viewv)方法添加需要的view。

下面是OneView.java界面文件：

public class OneView extends Activity{@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.one);}
}

下面是TwoView.java界面文件：

public class TwoView extends Activity{@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.two);}
}

下面是ThreeView.java界面文件：

public class TwoView extends Activity{@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.two);}
}

Take your time and enjoy it