自定义轮播图+网络请求

1.创建viewpa.xml

<?xml version="1.0" encoding="utf-8"?><RelativeLayout    xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    > <android.support.v4.view.ViewPager            android:id="@+id/viewpager"            android:layout_width="match_parent"            android:layout_height="match_parent" /></RelativeLayout>

2.创建自定义控件viewpage类

public class viewpager  extends RelativeLayout implements ViewPager.OnPageChangeListener {    //定义一个定时器    private Timer timer;    private  int  currentItemindex;     private ViewPager viewp;   private Handler handler = new Handler(){        @Override        public void handleMessage(Message msg) {            super.handleMessage(msg);             currentItemindex = viewp.getCurrentItem();            viewp.setCurrentItem(currentItemindex+1);        }    };    private ArrayList imageViews;    private ImageView imageView;    public viewpager(Context context) {        this(context,null);    }    public viewpager(Context context, AttributeSet attrs) {        this(context, attrs,0);    }    public viewpager(Context context, AttributeSet attrs, int defStyleAttr) {        super(context, attrs, defStyleAttr);        //创建自定义组件视图        View view= View.inflate(context, R.layout.viewpa,this);        viewp = (ViewPager) view.findViewById(R.id.viewpager);        viewp.addOnPageChangeListener(this);        //初始化定时器        timer = new Timer();      }   public void setAdapter(MyPagerAdapter myPagerAdapter){        viewp.setAdapter(myPagerAdapter);    }    //开启轮播  public void startAuto(){        //开始定时器        timer.scheduleAtFixedRate(new TimerTask() {            @Override            public void run() {             handler.sendEmptyMessage(0);            }        },0,3000);    }    @Override    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {    }    @Override    public void onPageSelected(int position) {    }    @Override    public void onPageScrollStateChanged(int state) {    }}

3.创建适配器MyPagerAdapter类

public class MyPagerAdapter extends PagerAdapter {    private Context context;   private List<TT>  list;    public MyPagerAdapter(Context context, List<TT> list) {        this.context = context;        this.list = list;    }    @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, final int position) {        ImageView imageView = new ImageView(context);        imageView.setScaleType(ImageView.ScaleType.FIT_XY);        //从网络上获取图片 ,需要到入一个Myapp的工具类        ImageLoader.getInstance().displayImage(list.get(position%list.size()).getIcon(),imageView, MyApp.getDefaultDisplayOption());        imageView.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                if(list.get(position%list.size()).getUrl()==""||list.get(position%list.size()).getUrl()==null)                {                }else{                    Intent intent = new Intent(context,Main2Activity.class);                    //  ("url",list.get(position).getUrl());                    Bundle bundle = new Bundle();                    bundle.putString("url",list.get(position%list.size()).getUrl());                    intent.putExtras(bundle);                    context.startActivity(intent);                } }        });        container.addView(imageView);        return imageView;    }    @Override    public void destroyItem(ViewGroup container, int position, Object object) {       // super.destroyItem(container, position, object);        container.removeView((View) object);    }}

4.MainAcitiviy

public class MainActivity extends AppCompatActivity {    ArrayList<TT> list = new ArrayList<>();    private viewpager dyvp;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        dyvp = (viewpager) findViewById(R.id.dyvp);        qingqiu();}    //网络请求    public  void qingqiu() {     MyTask myTask = new MyTask(new MyTask.Icallbacks() {            @Override            public void updateUiByjson(String jsonstr) {                Gson gson = new Gson();                Bean bean = gson.fromJson(jsonstr, Bean.class);                List<Bean.DataBean> data = bean.getData();                for (int i = 0; i < data.size(); i++) {                    String icon = data.get(i).getIcon();                    String title = data.get(i).getTitle();                    String url = data.get(i).getUrl();                    String[] split = title.split("|");                    list.add(new TT(icon, split[1],url));                }                MyPagerAdapter myPagerAdapter = new MyPagerAdapter(MainActivity.this ,list);                dyvp.setAdapter(myPagerAdapter);                dyvp.startAuto(); }});        myTask.execute("http://120.27.23.105/ad/getAd");    }}

5.在布局中使用自定义控件
导入工具类
Bean 类自己封装
添加网络权限’
TT是bean类自己封装