public  static  final  void collapseStatusBar(Context ctx) {
        Object sbservice = ctx.getSystemService("statusbar");
         try {
            Class<?> statusBarManager = Class.forName("android.app.StatusBarManager");
            Method collapse;
             if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
                collapse = statusBarManager.getMethod("collapsePanels");
            }  else {
                collapse = statusBarManager.getMethod("collapse");
            }
            collapse.invoke(sbservice);
        }  catch (Exception e) {
            e.printStackTrace();
        }
    }

     public  static  final  void expandStatusBar(Context ctx) {
        Object sbservice = ctx.getSystemService("statusbar");
         try {
            Class<?> statusBarManager = Class.forName("android.app.StatusBarManager");
            Method expand;
             if (Build.VERSION.SDK_INT >= 17) {
                expand = statusBarManager.getMethod("expandNotificationsPanel");
            }  else {
                expand = statusBarManager.getMethod("expand");
            }
            expand.invoke(sbservice);
        }  catch (Exception e) {
            e.printStackTrace();
        }
    }

     public  static  int getStatusBarHeight(Context context){
        Class<?> c =  null;
        Object obj =  null;
        Field field =  null;
         int x = 0, statusBarHeight = 0;
         try {
            c = Class.forName("com.android.internal.R$dimen");
            obj = c.newInstance();
            field = c.getField("status_bar_height");
            x = Integer.parseInt(field.get(obj).toString());
            statusBarHeight = context.getResources().getDimensionPixelSize(x);
        }  catch (Exception e1) {
            e1.printStackTrace();
        }
         return statusBarHeight;
    }

     public  static <T  extends View> T getAdapterView(View convertView,  int id) {
        SparseArray<View> viewHolder = (SparseArray<View>) convertView.getTag();
         if (viewHolder ==  null) {
            viewHolder =  new SparseArray<View>();
            convertView.setTag(viewHolder);
        }
        View childView = viewHolder.get(id);
         if (childView ==  null) {
            childView = convertView.findViewById(id);
            viewHolder.put(id, childView);
        }
         return (T) childView;
    }

    @Override
     public View getView( int position, View convertView, ViewGroup parent) {
         if (convertView ==  null) {
            convertView = LayoutInflater.from(getActivity()).inflate(R.layout.fragment_feed_item, parent,  false);
        }

        ImageView thumnailView = getAdapterView(convertView, R.id.video_thumbnail);
        ImageView avatarView =  getAdapterView(convertView, R.id.user_avatar);
        ImageView appIconView = getAdapterView(convertView, R.id.app_icon);

     < style  name ="TransparentActivity"  parent ="AppBaseTheme" >
         < item  name ="android:windowBackground" >@android:color/transparent </ item >
         < item  name ="android:colorBackgroundCacheHint" >@null </ item >
         < item  name ="android:windowIsTranslucent" >true </ item >
         < item  name ="android:windowNoTitle" >true </ item >
         < item  name ="android:windowContentOverlay" >@null </ item >
     </ style >

// 切换到全屏
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
getActivity().getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);

// 切换到非全屏
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);