项目中遇到一个需求，程序在一段时间没有操作的情况下退出登录，以此作为随笔记忆。

• 原理：在BaseActivity中重写dispatchTouchEvent方法，在MotionEvent.ACTION_UP事件中利用Handler发送一个延时消息，在MotionEvent.ACTION_DOWN事件中清空Handler消息队列，然后所有的Activity继承BaseActivity。

• 下面贴出BaseActivity代码：

    /**
     * Created by 一位不愿透露自己姓氏的先生 on 2017/8/23.
     */
  
        public class BaseActivity extends AppCompatActivity {
        
            @Override
            protected void onCreate(@Nullable Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                startAD();
            }
        
            private Handler handler = new Handler();
            private long time = 1000 * 5;
        
            @Override
            public boolean dispatchTouchEvent(MotionEvent event) {
                switch (event.getAction()) {
                    case MotionEvent.ACTION_DOWN:
                        handler.removeCallbacks(runnable);
                        break;
                    case MotionEvent.ACTION_UP:
                        startAD();
                        break;
                }
                return super.dispatchTouchEvent(event);
            }
        
            private Runnable runnable = new Runnable() {
                @Override
                public void run() {
                    PrefUtils.setBoolean(BaseActivity.this, "isLogin", false);
                    AlertDialog.Builder builder = new AlertDialog.Builder(BaseActivity.this);
                    builder.setTitle("温馨提示")
                            .setCancelable(false)
                            .setMessage("当前登录已失效，请重新登录")
                            .setPositiveButton("确定", new DialogInterface.OnClickListener() {
                                @Override
                                public void onClick(DialogInterface dialogInterface, int i) {
                                    Intent intent = new Intent();
                                    intent.setClass(BaseActivity.this, LoginActivity.class);
                                    startActivity(intent);
                                }
                            });
                    AlertDialog alertDialog = builder.create();
                    alertDialog.show();
                }
            };
        
            public void startAD() {
                handler.removeCallbacks(runnable);
                handler.postDelayed(runnable, time);
            }
        
        
            @Override
            protected void onDestroy() {
                super.onDestroy();
            }
        }
  

• 如果仅仅是这样是不能满足我们的需求的，例如我从MainActivity 跳到A Actiity的时候我不会将MainActivity销毁，那么当我在A Activity中长时间没有操作跳到登录页面登录之后再重新打开MainActivity的时候就会出问题，这个时候我们需要将所有打开的Activity全部关闭

• 解决方法：自定义一个Application,定义一个集合用来存放所有Actiity的实例，当我们需要退出的时候调用集合依次执行finish()；

• 下面贴出Application代码：

    /**
     * Created by 一位不愿透露自己姓氏的先生 on 2017/4/24.
     */
    
    public class DemoAppLication extends Application {
        private static DemoAppLication mycontext;
        private ArrayList<Activity> list;
    
        @Override
        public void onCreate() {
            super.onCreate();
            list = new ArrayList<>();
    
        }
    
        public void AddActivity(Activity activity) {
    
            list.add(activity);
    
        }
    
        public void exit() {
            try {
                for (Activity activity : list) {
                    if (activity != null)
                        activity.finish();
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    
    }
  

• 然后在BaseActivity获取Application的实例并保存代码修改如下：

    /**
     * Created by 一位不愿透露自己姓氏的先生 on 2017/8/23.
     */
    
    public class BaseActivity extends AppCompatActivity {
  
  
    public MiaoHuAppLication application;
  
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        application = (DemoLication) getApplication();
        startAD();
    }
  
    private Handler handler = new Handler();
    private long time = 1000 * 5;
  
         @Override
        public boolean dispatchTouchEvent(MotionEvent event) {
            switch (event.getAction()) {
                case MotionEvent.ACTION_DOWN:
                    handler.removeCallbacks(runnable);
                    break;
                case MotionEvent.ACTION_UP:
                    startAD();
                    break;
            }
            return super.dispatchTouchEvent(event);
        }
        
    private Runnable runnable = new Runnable() {
        @Override
        public void run() {
            PrefUtils.setBoolean(BaseActivity.this, "isLogin", false);
            AlertDialog.Builder builder = new AlertDialog.Builder(BaseActivity.this);
            builder.setTitle("温馨提示")
                    .setCancelable(false)
                    .setMessage("当前登录已失效，请重新登录")
                    .setPositiveButton("确定", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialogInterface, int i) {
                            Intent intent = new Intent();
                            intent.setClass(BaseActivity.this, LoginActivity.class);
                            startActivity(intent);
                            IMMessage.stop();
                            application.exit();
                        }
                    });
            AlertDialog alertDialog = builder.create();
            alertDialog.show();
        }
    };
  
    public void startAD() {
        handler.removeCallbacks(runnable);
        handler.postDelayed(runnable, time);
    }
  
  
    @Override
    protected void onDestroy() {
        super.onDestroy();
    }
    }
  

• 最后在每一个Activity中调用如下代码：

    application.AddActivity(this);
  

• 然后在需要关闭Activity的地方调用如下代码：

    application.exit();
  

不足之处还请各路大牛指点。