Viewpager实现真正的无限滑动,拒绝Integer.MAX_VALUE

package com.example.aa;

import android.content.Context;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.Toast;

/**
 * Created by lenovo on 2017/1/25.
 */
public class ViewPagerActivity extends AppCompatActivity{
    private ViewPager mBanner;
    private int ImageSize = 3;
    private int mImagesSrc[] = {R.drawable.guide1,R.drawable.guide2,R.drawable.guide3};
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_viewpager);

        ImageSize = mImagesSrc.length;

        mBanner  = (ViewPager) findViewById(R.id.viewpager);
        mBanner.setAdapter(new BannerAdapter(this));
    }



    private class BannerAdapter extends PagerAdapter{
        private LayoutInflater mInflater;

        public BannerAdapter(Context context) {
            mInflater = LayoutInflater.from(context);
        }
        @Override
        public int getCount() {
            return ImageSize+2;
        }

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

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            /**
             *    这个position是当前页面的下一个页面的缓存,若是想做滑动,position=当前item-1反之则加一
             *    举个例子这个viewpager总共包含了imagesize+2=7个页面
             *    positio=5时 position % ImageSize=0,切换到了第一个position
             */

            position %= ImageSize;
            View view = mInflater.inflate(R.layout.item, container, false);
            ImageView imageView = (ImageView) view.findViewById(R.id.meizi);
            imageView.setImageResource(mImagesSrc[position]);
            final int pos = position;
            view.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Toast.makeText(ViewPagerActivity.this, "点击item :" + pos, Toast.LENGTH_SHORT).show();
                }
            });

            container.addView(view);
            return view;
        }

        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            Log.d("", "destroyItem%" + mBanner.getCurrentItem() + "sssss" + position);
            container.removeView((View) object);
        }

        @Override
        public void finishUpdate(ViewGroup container) {
            int position = mBanner.getCurrentItem();
            /**
             *  第五这里获得当前的positon然后对其setCurrentItem进行变换
             *  这里设置当position=0时把position设置为图片列表的最大值
             *  是为了position=0时左滑显示最后一张,我举个例子这里ImageSize是5
             *  当position==0时设置为5,左滑就是position=4,也就是第五张图片,
             *
             *  if (position == (ImageSize+2) - 1)
             *  这个判断 (ImageSize+2)这个是给viewpager设置的页面数,这里是7
             *  当position==7-1=6时,这时viewpager就滑到头了,所以把currentItem设置为1
             *  这里设置为1还是为了能够左滑,这时左滑position=0又执行了第一个判断又设置为5,
             *  这样就实现了无限轮播的效果
             *  setCurrentItem(position,false);
             *  这里第二个参数false是消除viewpager设置item时的滑动动画,不理解的去掉它运行下就知道啥意思了
             *
             *  一进来时,position=0,走第一个if(position=3);
             *      左滑:2——1——0(3)——2——1——0(3)...
             *      右滑:4(1)——2——3——4(1)...
             *
             */
            Log.i("", "finishUpdate: "+position);
            if (position == 0) {
                Log.i("", "position: "+position);
                position = ImageSize;
                mBanner.setCurrentItem(position,false);
            } else if (position == (ImageSize+2) - 1) {
                Log.i("", "position: "+position);
                position = 1;
                mBanner.setCurrentItem(position,false);
            }
        }

    }


}

参考:http://blog.csdn.net/verzqli/article/details/54620327

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