RadioGroup 和 ViewPager 绑定 实现切换

package com.jereh.helloworld.activity.day12;
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.widget.ImageView;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import com.jereh.helloworld.R;
import com.jereh.helloworld.activity.adapter.GuidePagerAdapter;
import com.jereh.helloworld.activity.entity.NewsType;
import java.util.ArrayList;
import java.util.List;
public class Day12Test3Activity extends Activity {
    private List<NewsType> list;
    private RadioGroup radioGroup;
    private ViewPager viewPager;
    private int[] imgs = {
            R.drawable.wangfei1,
            R.drawable.wangfei2,
            R.drawable.wangfei3,
            R.drawable.wangfei4,
            R.drawable.wangfei5,
            R.drawable.wangfei6,
            R.drawable.wangfei7};
    private List<ImageView> list1 = new ArrayList<>();
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_day12_test3);
        viewPager = (ViewPager)findViewById(R.id.viewPager);
        for (int i : imgs) {
            ImageView imageView = new ImageView(this);
            imageView.setImageResource(i);
            imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
            list1.add(imageView);
        }
        viewPager.setAdapter(new GuidePagerAdapter(list1));
        viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
            }
            @Override
            public void onPageSelected(int position) {
                RadioButton radioButton = (RadioButton)radioGroup.getChildAt(position);
                radioButton.setChecked(true);
            }
            @Override
            public void onPageScrollStateChanged(int state) {
            }
        });
        initNewsType();
        radioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(RadioGroup group, int checkedId) {
                viewPager.setCurrentItem(checkedId);
            }
        });
        initNewsTypeUi();
    }
    private void initNewsTypeUi(){
        LayoutInflater inflater = LayoutInflater.from(this);
        radioGroup = (RadioGroup)findViewById(R.id.tabs);
        for (int i = 0;i<list.size();i++) {
            RadioButton radioButton =(RadioButton)
            inflater.inflate(R.layout.news_type_radiobutton,null,false);
            radioButton.setId(i);
            radioButton.setText(list.get(i).getName());
            if (i==0){
                radioButton.setChecked(true);
            }
            radioGroup.addView(radioButton);
        }
    }
    private void initNewsType(){
        list = new ArrayList<>();
        list.add(new NewsType(1,"推荐"));
        list.add(new NewsType(2,"热点"));
        list.add(new NewsType(3,"社会"));
        list.add(new NewsType(4,"国际"));
        list.add(new NewsType(5,"国内"));
        list.add(new NewsType(6,"娱乐"));
        list.add(new NewsType(7,"体育"));
        list.add(new NewsType(8,"科技"));
        list.add(new NewsType(9,"时尚"));
        list.add(new NewsType(10,"生活"));
    }
}