imageview+handler+gridview+上拉下拉

public class Fragment01 extends Fragment{    private PullToRefreshScrollView refreshScrollView;    private ILoadingLayout startLabels;    private int page_num = 1;    private ImageView imageview;    private GridView gridview;    private GridView_Adapter adapter;    private List<DataDataBean.ResultBean.DataBean> list = new ArrayList<>();    private List<String > blist = new ArrayList<>();    private int index = 0;    private Handler handler = new Handler(){        @Override        public void handleMessage(Message msg) {            if (msg.what == 0){                //接到消息之后,,,切换图片显示                index ++;                ImageLoader.getInstance().displayImage(String.valueOf(list.get(index %list.size())),imageview, ImageLoaderUtil.getDefaultOption());                //再次发送                handler.sendEmptyMessageDelayed(0,3000);            }        }    };    @Nullable    @Override    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {        View view=inflater.inflate(R.layout.fragment01,container,false);        refreshScrollView=view.findViewById(R.id.refresh_scroll_view);        imageview=view.findViewById(R.id.imageview);        gridview=view.findViewById(R.id.gridview);        return view;    }    @Override    public void onActivityCreated(@Nullable Bundle savedInstanceState) {        super.onActivityCreated(savedInstanceState);        gridview.setFocusable(false);        getDataFromNet();        getFrom();        //2.设置刷新模式        /*设置pullToRefreshListView的刷新模式，BOTH代表支持上拉和下拉，PULL_FROM_END代表上拉,PULL_FROM_START代表下拉 */        refreshScrollView.setMode(PullToRefreshBase.Mode.BOTH);        //3.通过getLoadingLayoutProxy 方法来指定上拉和下拉时显示的状态的区别(也就是设置向下拉的时候头部里面显示的文字)        //此时这里设置的是下拉刷新的时候显示的文字,所以第一个设置true表示现在是刷新,第二个设置为false        startLabels = refreshScrollView.getLoadingLayoutProxy(true, false);        startLabels.setPullLabel("下拉刷新");        startLabels.setRefreshingLabel("正在刷新...");        startLabels.setReleaseLabel("放开刷新");        ILoadingLayout endLabels = refreshScrollView.getLoadingLayoutProxy(false, true);        endLabels.setPullLabel("上拉刷新");        endLabels.setRefreshingLabel("正在载入...");        endLabels.setReleaseLabel("放开刷新...");        /**         * 监听事件         */        refreshScrollView.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener2<ScrollView>() {            @Override            public void onPullDownToRefresh(PullToRefreshBase<ScrollView> refreshView) {                getRefreshData();            }            @Override            public void onPullUpToRefresh(PullToRefreshBase<ScrollView> refreshView) {                page_num++;                getDataFromNet();            }        });    }    //imageview+handler 3秒换图片    public void getFrom() {        NetDataUtil.getData(getActivity(), "http://apis.juhe.cn/cook/query?key=65481ae0fb17703c15a794aebaec93c5&menu=%E8%A5%BF%E7%BA%A2%E6%9F%BF&rn=11&pn=4", new JsonCallBack() {            @Override            public void getJson(String s) {                //解析                Gson gson = new Gson();                DataDataBean dataDataBean = gson.fromJson(s, DataDataBean.class);                List<DataDataBean.ResultBean.DataBean.StepsBean> steps = dataDataBean.getResult().getData().get(0).getSteps();                for (DataDataBean.ResultBean.DataBean.StepsBean st: steps) {                    blist.add(st.getImg());                }                //现在图片集合有数据,,,,展示图片,,,展示第一张图片                ImageLoader.getInstance().displayImage(blist.get(0),imageview,ImageLoaderUtil.getDefaultOption());                //发送延时消息                handler.sendEmptyMessageDelayed(0,3000);                                    }        });    }    /**     * 下拉刷新获取数据     */    private void getRefreshData() {        NetDataUtil.getData(getActivity(),"http://apis.juhe.cn/cook/query?key=65481ae0fb17703c15a794aebaec93c5&menu=%E8%A5%BF%E7%BA%A2%E6%9F%BF&rn=11&pn=4",  new JsonCallBack() {            @Override            public void getJson(String json) {                //解析                Gson gson = new Gson();                DataDataBean dataDataBean4 = gson.fromJson(json, DataDataBean.class);                //先清空一下数据                list.clear();                //添加到集合的最前边,,,,(0,,,,)                list.addAll(0, dataDataBean4.getResult().getData());                //设置适配器                setAdapter();                //设置适配器之后停止刷新的操作                refreshScrollView.onRefreshComplete();                //可以设置刷新的时间....                startLabels.setLastUpdatedLabel("上次更新时间:" + new SimpleDateFormat("HH:mm").format(new Date(System.currentTimeMillis())));//last最近的,最后一次update修改/更新            }        });    }    /**     * 刚开始进入页面获取网络数据....还可以作为上拉加载获取数据的操作     */    private void getDataFromNet() {        //第一个参数是接口,第二个上下文,第三个回调json数据        NetDataUtil.getData(getActivity(),"http://apis.juhe.cn/cook/query?key=65481ae0fb17703c15a794aebaec93c5&menu=%E8%A5%BF%E7%BA%A2%E6%9F%BF&rn=11&pn=4" + page_num,  new JsonCallBack() {            @Override            public void getJson(String json) {                //解析                Gson gson = new Gson();                DataDataBean dataDataBean = gson.fromJson(json, DataDataBean.class);                //往后面添加...                list.addAll(dataDataBean.getResult().getData());                //设置适配器                setAdapter();                //停止刷新                refreshScrollView.onRefreshComplete();            }        });    }     //适配器    private void setAdapter(){        if(adapter==null){            adapter = new GridView_Adapter(getActivity(),list);            gridview.setAdapter(adapter);        }else{            adapter.notifyDataSetChanged();        }    }}