周考三模拟

mainActity

public class MainActivity extends AppCompatActivity {

    private PullToRefreshScrollView psv;

    private int pageIndex=1;
    private int operType=1;//1:刷新 2：加载更多

    private String myurl="http://365jia.cn/news/api3/365jia/news/headline?page="+pageIndex;

    private  List<ResultData.DataBeanX.DataBean> datas=new ArrayList<>();
    private ListViewAdapter adapter;
    private ListView listView;
    private ViewPager viewPager;
    private List<String> imgUrls=new ArrayList<>();
    private LinearLayout linPoint;

    private List<ImageView> lists=new ArrayList<>();
    private Handler mHandler=new Handler(){
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);

            int cIndex=viewPager.getCurrentItem();
            cIndex++;
            viewPager.setCurrentItem(cIndex);

            //改变指示器
            setSelectedPoint(cIndex%lists.size());

            sendEmptyMessageDelayed(0,1000);
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        psv = findViewById(R.id.psv);
        listView = findViewById(R.id.lv);
        viewPager = findViewById(R.id.vp);
        linPoint = findViewById(R.id.lin_point);

        //初使化 pullToRefreshScrollView

        initPsv();

        //请求网络数据
        requestNetData();

    }

    private void requestNetData() {
        new MyTask().execute(myurl);

    }
    class MyTask extends AsyncTask<String,Void,String> {

        @Override
        protected String doInBackground(String... strings) {
            try {
                URL url=new URL(strings[0]);
                HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

                urlConnection.setRequestMethod("GET");
                urlConnection.setReadTimeout(5000);
                urlConnection.setConnectTimeout(5000);

                if(urlConnection.getResponseCode()==200){
                    InputStream inputStream = urlConnection.getInputStream();

                    String s = streamToString(inputStream);
                    return s;
                }
            } catch (Exception e) {
                e.printStackTrace();
            }

            return null;
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);

            Gson gson=new Gson();
            ResultData resultData = gson.fromJson(s, ResultData.class);
            //新请求下来的数据
            List<ResultData.DataBeanX.DataBean> data = resultData.getData().getData();

            //展示轮播图
            showPics(data);


            if(operType==1){
                datas.clear();//清空
            }
            datas.addAll(data);

            setAdapter();

            //关闭头尾布局
            psv.onRefreshComplete();
        }
    }

    private void showPics(List<ResultData.DataBeanX.DataBean> data) {
        imgUrls.clear();
        //为轮播图添加地址
        imgUrls.add("http://365jia.cn/uploads/"+data.get(0).getPics().get(0));
        imgUrls.add("http://365jia.cn/uploads/"+data.get(1).getPics().get(0));
        imgUrls.add("http://365jia.cn/uploads/"+data.get(2).getPics().get(0));

        MyVpAdapter adapter=new MyVpAdapter(imgUrls,MainActivity.this);
        viewPager.setAdapter(adapter);

        //初使化指示器
        initPoint();


        //发送消息，实现自动轮播
        mHandler.sendEmptyMessageDelayed(0,1000);
    }

    //设置选中的小圆点
    private  void setSelectedPoint(int pageIndex){
        for (int i = 0; i <lists.size() ; i++) {
            if(i==pageIndex){
                lists.get(i).setImageResource(R.drawable.point_selected);
            }else {
                lists.get(i).setImageResource(R.drawable.point_unselected);
            }

        }

    }

    private void initPoint() {
        for (int i = 0; i <imgUrls.size() ; i++) {
            ImageView imageView=new ImageView(this);
            //设置它的布局参数
            LinearLayout.LayoutParams params=new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,LinearLayout.LayoutParams.WRAP_CONTENT);
            params.setMargins(0,0,10,0);//设置右边的间隔
            if(i==0){
                imageView.setImageResource(R.drawable.point_selected);//选中的小圆点
            }else{
                imageView.setImageResource(R.drawable.point_unselected);
            }
            linPoint.addView(imageView,params);

            lists.add(imageView);
        }

    }

    public void setAdapter(){
        if (adapter == null) {
            adapter = new ListViewAdapter(datas,MainActivity.this);
            listView.setAdapter(adapter);
        }else {
            adapter.notifyDataSetChanged();
        }

    }

    /**
     * 将流转换成String
     * @param stream
     */
    private String streamToString(InputStream stream) {
        StringBuilder sbuilder=new StringBuilder();
        String str;
        BufferedReader reader=new BufferedReader(new InputStreamReader(stream));

        try {
            while ((str=reader.readLine())!=null){
                sbuilder.append(str);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return  sbuilder.toString();

    }

    private void initPsv() {
        //1.设置模式
        psv.setMode(PullToRefreshBase.Mode.BOTH);
        //2.设置监听
        psv.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener2<ScrollView>() {
            @Override
            public void onPullDownToRefresh(PullToRefreshBase<ScrollView> pullToRefreshBase) {
                //刷新回调
                operType=1;
                pageIndex=1;
                myurl="http://365jia.cn/news/api3/365jia/news/headline?page="+pageIndex;
                requestNetData();

            }

            @Override
            public void onPullUpToRefresh(PullToRefreshBase<ScrollView> pullToRefreshBase) {
                //加载回调
                operType=2;
                pageIndex++;
                myurl="http://365jia.cn/news/api3/365jia/news/headline?page="+pageIndex;
                requestNetData();

            }
        });
    }

}

ListViewAdapter
public class ListViewAdapter extends BaseAdapter {
    private  List<ResultData.DataBeanX.DataBean> data;
    private Context context;

    public ListViewAdapter( List<ResultData.DataBeanX.DataBean> data, Context context) {
        this.data = data;
        this.context = context;
    }

    @Override
    public int getCount() {
        return data.size();
    }

    @Override
    public Object getItem(int i) {
        return data.get(i);
    }

    @Override
    public long getItemId(int i) {
        return i;
    }

    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {
        ViewHolder holder;
        if(view==null){
            view=View.inflate(context,R.layout.lvitem,null);
            holder=new ViewHolder();
            holder.textView=view.findViewById(R.id.tv);


            view.setTag(holder);
        }else {
            holder= (ViewHolder) view.getTag();
        }

        holder.textView.setText(data.get(i).getTitle());

        return view;
    }

    class ViewHolder{
        TextView textView;
    }
}

Application

public class MyApplication extends Application {

    @Override
    public void onCreate() {
        super.onCreate();

        //自定义图片的缓存路径
        File cachefile=new File( Environment.getExternalStorageDirectory().getPath()+"/abc");


        ImageLoaderConfiguration configuration=new ImageLoaderConfiguration.Builder(this)
                .memoryCacheExtraOptions(480, 800)//缓存图片最大的长和宽
                .threadPoolSize(2)//线程池的数量
                .threadPriority(4)
                .memoryCacheSize(2*1024*1024)//设置内存缓存区大小
                .diskCacheSize(20*1024*1024)//设置sd卡缓存区大小
                .diskCache(new UnlimitedDiscCache(cachefile))//自定义缓存目录
                .writeDebugLogs()//打印日志内容
                .diskCacheFileNameGenerator(new Md5FileNameGenerator())//给缓存的文件名进行md5加密处理
                .build();
        ImageLoader.getInstance().init(configuration);

    }
}

Mylistview

public class MyListView extends ListView {
    public MyListView(Context context) {
        super(context);
    }

    public MyListView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    //测量
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        //重新计算高度
        int newHeight=MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE>>2,MeasureSpec.AT_MOST);
        super.onMeasure(widthMeasureSpec, newHeight);
    }
}

MyVpAdapter

public class MyVpAdapter extends PagerAdapter {

    //数据源
    private List<String> urls;
    //上下文对象
    private Context context;

    private DisplayImageOptions options;

    public MyVpAdapter(List<String> urls, Context context) {
        this.urls = urls;
        this.context = context;
        this.options=new DisplayImageOptions.Builder()
                .cacheInMemory(true)//使用内存缓存
                .cacheOnDisk(true)//使用磁盘缓存
                .showImageOnLoading(R.mipmap.ic_launcher)//设置正在下载的图片
                .showImageForEmptyUri(R.mipmap.ic_launcher)//url为空或请求的资源不存在时
                .showImageOnFail(R.mipmap.ic_launcher)//下载失败时显示的图片
                .bitmapConfig(Bitmap.Config.RGB_565)//设置图片色彩模式  1px=2个字节  ARGB_8888 1px=4个字节   ARGB_4444 1px=2个字节  ALPHA_8 1px=1个字节
                .imageScaleType(ImageScaleType.EXACTLY)//设置图片的缩放模式
                .build();
    }

    @Override
    public int getCount() {
        return Integer.MAX_VALUE;
    }

    @Override
    public boolean isViewFromObject(View view, Object object) {
        return view==object;
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        ImageView imageView=new ImageView(context);
        //下载图片
        ImageLoader.getInstance().displayImage(urls.get(position%urls.size()),imageView,options);

        container.addView(imageView);
        return imageView;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        //super.destroyItem(container, position, object);
        container.removeView((View)object);
    }
}