ViewPager 滑动页（一）

需求：滑动展示页，能够使用本地数据，及获取服务器数据进行刷新操作；

效果图：

实现分析：

1.目录结构：

代码实现：

1.fragment_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.jjc.demo.MainActivity$PlaceholderFragment" >

    <com.jjc.demo.PosterView
        android:id="@+id/poster"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</RelativeLayout>

2.view_poster.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    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" />

    <LinearLayout
        android:id="@+id/container"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:gravity="center"
        android:background="@android:color/transparent"
        android:orientation="horizontal" />

</FrameLayout>

3.item_poster.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <ImageView
        android:id="@+id/image_pic"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scaleType="centerCrop" />

</FrameLayout>

4.poster_point_selector.xml

<?xml version="1.0" encoding="UTF-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:state_enabled="true"><bitmap android:src="@drawable/point_normal" />
    </item>
    <item android:state_enabled="false"><bitmap android:src="@drawable/point_select" />
    </item>

</selector>

5.PosterView.java

package com.jjc.demo;

import java.util.ArrayList;
import java.util.List;

import android.content.Context;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.LinearLayout;

public class PosterView extends FrameLayout{

    private Context context;
    private ViewPager viewPager;
    private LinearLayout container;

    private PosterAdapter adapter;

    private List<Integer> posterList = new ArrayList<Integer>();

    private ImageView imageView;
    // 底部小点的图片
    private ImageView[] points;

    // 记录当前选中位置
    private int currentIndex = 0;
//    private int nextIndex;
    private int pageNum = 1;

    public PosterView(Context context) {
        this(context, null);
    }

    public PosterView(Context context, AttributeSet attrs) {
        super(context, attrs);
        this.context = context;
        LayoutInflater.from(context).inflate(R.layout.view_poster, this, true);
        initView();
    }

    private void initView(){
        container = (LinearLayout) findViewById(R.id.container);
        viewPager = (ViewPager)findViewById(R.id.viewpager);
        viewPager.setOnPageChangeListener(new viewpagerListener());

        adapter = new PosterAdapter(context, posterList);
        viewPager.setAdapter(adapter);
    }

    /**
     * 刷新海报页数据；
     * @param list
     */
    public void refreshData(List<Integer> list){
        if(list == null || list.isEmpty()){
            return;
        }
        initPoint(list.size());

        posterList.clear();
        posterList.addAll(list);
        adapter.notifyDataSetChanged();
    }

    private void initPoint(int num){
        pageNum = num;
        container.removeAllViews();

        if(num == 0){
            return;
        }

        points = new ImageView[num];
        for (int i = 0; i < num; i++) {
            imageView = new ImageView(context);
            imageView.setBackgroundResource(R.drawable.poster_point_selector);

            LinearLayout.LayoutParams mLayoutParams = new LinearLayout.LayoutParams(12, 12);
            mLayoutParams.rightMargin = 8;
            mLayoutParams.leftMargin = 8;
            mLayoutParams.topMargin = 24;
            mLayoutParams.bottomMargin = 28;

            points[i] = imageView;
            // 设置位置tag，方便取出与当前位置对应
            points[i].setTag(i);
            // 默认都设为灰色
            points[i].setEnabled(false);
            // 给每个小点设置监听
            points[i].setOnClickListener(new pointListener());
            container.addView(points[i], mLayoutParams);
        }
        // 设置为白色，即选中状态
        points[currentIndex].setEnabled(true);
    }

    private class viewpagerListener implements OnPageChangeListener {

        @Override
        public void onPageScrollStateChanged(int arg0) {
        }

        @Override
        public void onPageScrolled(int arg0, float arg1, int arg2) {
        }

        @Override
        public void onPageSelected(int position) {
            // 设置底部小点选中状态
            setCurDot(position);
        }
    }

    private class pointListener implements OnClickListener {

        @Override
        public void onClick(View v) {
            int position = (Integer) v.getTag();
            setCurView(position);
            setCurDot(position);
        }
    }

    /**
     * 设置当前页面的位置
     */
    private void setCurView(int position) {
        if (position < 0 || position >= pageNum) {
            return;
        }
        viewPager.setCurrentItem(position);
    }

    /**
     * 设置当前的小点的位置
     */
    private void setCurDot(int positon) {
        if (positon < 0 || positon > pageNum - 1 || currentIndex == positon) {
            return;
        }
        points[positon].setEnabled(true);
        points[currentIndex].setEnabled(false);
        currentIndex = positon;
    }

}

6.PosterAdapter.java

package com.jjc.demo;

import java.util.List;

import android.content.Context;
import android.support.v4.view.PagerAdapter;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;

public class PosterAdapter extends PagerAdapter {

//    private Context context;
    private List<Integer> posterList;

    private LayoutInflater inflater;

    public PosterAdapter(Context context, List<Integer> posterList) {
//        this.context = context;
        this.posterList = posterList;
        inflater = LayoutInflater.from(context);
    }

    @Override
    public int getCount() {
        return posterList.isEmpty() ? 0 : posterList.size();
    }

    @Override
    public boolean isViewFromObject(View arg0, Object arg1) {
        return arg0 == arg1;
    }

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

    @Override
    public Object instantiateItem(ViewGroup container, int position) {

        View view = container.findViewById(position);
        ViewHolder holder;

        if(view == null){
            holder = new ViewHolder();
            view = inflater.inflate(R.layout.item_poster, null);
            //为View设置标识符，可通过findViewById方法获取
            view.setId(position);
            holder.icon = (ImageView)view.findViewById(R.id.image_pic);
            container.addView(view);
            view.setTag(holder);
        }else{
            holder = (ViewHolder)view.getTag();
        }
        holder.icon.setImageResource(posterList.get(position));

        return view;
    }

    static class ViewHolder{
        ImageView icon;
    }
}

7.MainActivity.java

package com.jjc.demo;

import java.util.ArrayList;
import java.util.List;

import android.support.v7.app.ActionBarActivity;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class MainActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        if (savedInstanceState == null) {
            getSupportFragmentManager().beginTransaction()
                    .add(R.id.container, new PlaceholderFragment()).commit();
        }
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment {

        private View rootView;
        private PosterView posterView;

        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            rootView = inflater.inflate(R.layout.fragment_main, container, false);
            return rootView;
        }

        @Override
        public void onActivityCreated(Bundle savedInstanceState) {
            super.onActivityCreated(savedInstanceState);
            initView();
        }

        private void initView() {
            posterView = (PosterView)rootView.findViewById(R.id.poster);

//            posterView.setBackgroundResource(R.drawable.poster_02);
            List<Integer> images = new ArrayList<Integer>();
            images.add(R.drawable.poster_01);
            images.add(R.drawable.poster_02);
            images.add(R.drawable.poster_03);
            images.add(R.drawable.poster_04);
            images.add(R.drawable.poster_05);
            posterView.refreshData(images);

        }
    }

}

代码：http://pan.baidu.com/s/1mgHWqrY