ViewPager总结

https://github.com/youth5201314/banner

1.添加布局fragment_hall_head.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/transparent"
    android:orientation="vertical">
    <FrameLayout

        android:id="@+id/fl"
        android:layout_width="match_parent"
        android:layout_height="300px">

        <android.support.v4.view.ViewPager
            android:id="@+id/viewPager"
            android:layout_width="match_parent"
            android:layout_height="300px" />

        <LinearLayout
            android:id="@+id/ll_points"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="bottom|center_horizontal"
            android:layout_marginBottom="11dp"
            android:orientation="horizontal" />

    </FrameLayout>
</LinearLayout>

2.添加资源文件

shape_xiao_yuan_quan_selected.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">
    <size
        android:width="8dp"
        android:height="8dp" />
    <stroke
        android:width="1px"
        android:color="@color/colorAccent" />
    <solid android:color="@color/colorAccent" />
</shape>

shape_xiao_yuan_quan_nomal.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">
    <size
        android:width="8dp"
        android:height="8dp" />
    <stroke
        android:width="1px"
        android:color="@color/white" />
    <solid android:color="@color/white" />
</shape>

3.查找控件

List<String> imgesUrl = new ArrayList<>();
imgesUrl.add("http://img3.fengniao.com/forum/attachpics/913/114/36502745.jpg");
imgesUrl.add("http://imageprocess.yitos.net/images/public/20160910/99381473502384338.jpg");
imgesUrl.add("http://imageprocess.yitos.net/images/public/20160910/77991473496077677.jpg");
imgesUrl.add("http://imageprocess.yitos.net/images/public/20160906/1291473163104906.jpg");
Banner banner = new Banner(MainActivity.this, imgesUrl, findViewById(R.id.fl));

4.添加动画类：

import android.content.Context;
import android.os.Handler;
import android.os.Message;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.LinearLayout;

import java.util.List;

/**
 * Created by Administrator on 2017/2/28.
 */

public class Banner {
    private LinearLayout llPoints; //图片里面的小圆点
    private ViewPager viewPager;  //图片轮播
    List<String> imgesUrl;
    Context context;
    View view;

    public Banner(Context context, List<String> imgesUrl, View view) {
        this.context = context;
        this.imgesUrl = imgesUrl;
        this.view = view;
        viewPager = (ViewPager) view.findViewById(R.id.viewPager);
        llPoints = (LinearLayout) view.findViewById(R.id.ll_points);
        startBanner();
    }

    /**
     * 处理轮播图
     */

    public void startBanner() {
        MyPagerAdapter myPagerAdapter = new MyPagerAdapter();
        viewPager.setAdapter(myPagerAdapter);
        viewPager.setCurrentItem(imgesUrl.size() * 10000);
        startRool();
        //初始化ViewPager轮播小圆圈
        llPoints.removeAllViews();
        for (int i = 0; i < imgesUrl.size(); i++) {
            ImageView point = new ImageView(context);
            if (i == 0) {
                point.setImageResource(R.drawable.shape_xiao_yuan_quan_selected);
            } else {
                point.setImageResource(R.drawable.shape_xiao_yuan_quan_nomal);
            }
            LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
            if (i > 0) {
                params.leftMargin = dp2px(context, 8);
            }
            llPoints.addView(point, params);
        }
        //ViewPager的轮播效果(小圆圈改变)
        viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageSelected(int position) {
                position = position % imgesUrl.size();
                for (int i = 0; i < llPoints.getChildCount(); i++) {
                    ImageView image = (ImageView) llPoints.getChildAt(i);
                    if (i == position) {
                        image.setImageResource(R.drawable.shape_xiao_yuan_quan_selected);
                    } else {
                        image.setImageResource(R.drawable.shape_xiao_yuan_quan_nomal);
                    }
                }
            }

            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

            }

            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });

    }

   /**
     * 轮播图的adapter
     */

    class MyPagerAdapter extends PagerAdapter {
        @Override
        public int getCount() {
            return Integer.MAX_VALUE;
        }

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

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

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            ImageView imageView = new ImageView(context);
            imageView.setScaleType(ImageView.ScaleType.FIT_XY);
//            ImageLoader.getInstance().displayImage(imgesUrl.get(position % imgesUrl.size()), imageView);
            imageView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {

                }
            });
            imageView.setOnTouchListener(new View.OnTouchListener() {

                public boolean onTouch(View v, MotionEvent event) {
                    switch (event.getAction()) {
                        case MotionEvent.ACTION_DOWN:
                            handler.removeCallbacksAndMessages(null);
                            break;
                        case MotionEvent.ACTION_UP:
                            handler.sendEmptyMessageDelayed(1, 2000);
                            break;
                        /**
                         * 当保持按下操作，并从此控件移到外层控件时，就会触发ACTION_CANCEL事件时，
                         * 当前的手势被中断，不会在接收它的记录
                         * 将它当做ACTION_UP事件进行处理比较好
                         */
                        case MotionEvent.ACTION_CANCEL:
                            handler.sendEmptyMessageDelayed(1, 2000);
                            break;

                        default:
                            break;
                    }
                    // true处理这个事件
                    return true;
                }
            });

            container.addView(imageView);
            return imageView;
        }
    }

    Handler handler = new Handler() {

  @Override
        public void handleMessage(Message msg) {
            if (msg.what == 1) {
                int currentItem = viewPager.getCurrentItem();
                currentItem++;
                viewPager.setCurrentItem(currentItem);
                startRool();
            }
        }

    };

    private void startRool() {
        handler.sendEmptyMessageDelayed(1, 3000);
    }

    public static int dp2px(Context context, int dp) {
        // 获取像素密码
        float density = context.getResources().getDisplayMetrics().density;
        return (int) (dp * density + 0.5f);
    }
}