Android 架构

import   java.util.ArrayList;
import   java.util.List;

import   android.app.Activity;
import   android.app.Application;


/**
 * 应用配置类
 * @author leehongee
 *
 */
public   class   AppManager extends   Application{
    /**打开的activity**/
    private   List<Activity> activities = new   ArrayList<Activity>();
    /**应用实例**/
    private   static   AppManager instance;
    /**
     *  获得实例
     * @return
     */
    public   static   AppManager getInstance(){
        return   instance;
    }
    /**
     * 新建了一个activity
     * @param activity
     */
    public   void   addActivity(Activity activity){
        activities.add(activity);
    }
    /**
     *  结束指定的Activity
     * @param activity
     */
    public   void   finishActivity(Activity activity){
        if   (activity!= null ) {
            this .activities.remove(activity);
            activity.finish();
            activity = null ;
        }
    }
    /**
     * 应用退出，结束所有的activity
     */
    public   void   exit(){
        for   (Activity activity : activities) {
            if   (activity!= null ) {
                activity.finish();
            }
        }
        System.exit( 0 );
    }

    @Override
    public   void   onCreate() {
            instance = this ;
    }
}

 然后我写了一个BaseActivity，以后的Activity 都继承这个Activity，如下

import   android.app.Activity;
import   android.os.Bundle;
import   android.os.StrictMode;

/**
 * 基本Activity
 * @author leehongee
 * @date 2013-1-26 下午6:24:47
 * @version
 */
public   class   BaseActivity extends   Activity{

    @Override
    protected   void   onCreate(Bundle savedInstanceState) {
        super .onCreate(savedInstanceState);
        //添加到Activity集合
        AppManager.getInstance().addActivity( this );
        //手机端SDK>10，即 android 2.3.x之后在主线程中访问网络需要加入如下代码
        if   (AppConfig.getSDKVersionNumber()> 10 ) {
            // 详见StrictMode文档
            StrictMode.setThreadPolicy( new   StrictMode.ThreadPolicy.Builder()
                    .detectDiskReads()
                    .detectDiskWrites()
                    .detectNetwork()   // or .detectAll() for all detectable problems
                    .penaltyLog()
                    .build());
            StrictMode.setVmPolicy( new   StrictMode.VmPolicy.Builder()
                    .detectLeakedSqlLiteObjects()
                    .detectLeakedClosableObjects()
                    .penaltyLog()
                    .penaltyDeath()
                    .build());
        }
    }

    @Override
    public   void   onBackPressed() {
        super .onBackPressed();
        onDestroy();
    }

    @Override
    protected   void   onDestroy() {
        super .onDestroy();
        //结束Activity&从集合中移除
        AppManager.getInstance().finishActivity( this );
    }

}