Android中使用ViewPager实现图片的切换

主要包含三步，配置布局文件，设置MainActivity类，配置适配器类

.xml文件：

<LinearLayout 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:orientation="vertical" >    <TextView        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:gravity="center"        android:text="请选择图片"        android:textColor="#ff0000"        android:textSize="20sp" />    <FrameLayout        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="wrap_content" />        <LinearLayout            android:id="@+id/viewGroup"            android:layout_width="fill_parent"            android:layout_height="wrap_content"            android:layout_alignParentBottom="true"            android:layout_marginBottom="30dp"            android:gravity="center_horizontal"            android:orientation="horizontal" >        </LinearLayout>    </FrameLayout></LinearLayout>

MainActivity类：

package com.example.android_005_viewpager;import java.util.ArrayList;import java.util.List;import android.app.Activity;import android.os.Bundle;import android.support.v4.view.ViewPager;import android.support.v4.view.ViewPager.OnPageChangeListener;import android.view.Menu;import android.view.MenuItem;import android.view.ViewGroup;import android.view.ViewGroup.LayoutParams;import android.view.Window;import android.widget.ImageView;public class MainActivity extends Activity {// 装图片id的数组private int[] bitmaps = {R.drawable.yanshi, R.drawable.yanshi, R.drawable.yanshi,R.drawable.yanshi, R.drawable.yanshi, R.drawable.ic_launcher,R.drawable.ie_arrow_normal };private ViewPager viewpager;private List<ImageView> list;// 装ImageView的集合private ImageView imageView;private ImageView[] tips;// 装点点的集合private ViewGroup viewGroup;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);requestWindowFeature(Window.FEATURE_NO_TITLE);setContentView(R.layout.activity_main);viewpager = (ViewPager) findViewById(R.id.viewPager);viewGroup = (ViewGroup) findViewById(R.id.viewGroup);// 将imageView图片资源存在集合中list = new ArrayList<ImageView>();for (int i = 0; i < bitmaps.length; i++) {imageView = new ImageView(MainActivity.this);imageView.setBackgroundResource(bitmaps[i]);// 为imageView设置tag，将id传入，方便页面跳转时，发送图片的资源idimageView.setTag(bitmaps[i]);list.add(imageView);}// 将点点装入到结集合中tips = new ImageView[bitmaps.length];for (int i = 0; i < bitmaps.length; i++) {imageView = new ImageView(MainActivity.this);imageView.setLayoutParams(new LayoutParams(100, 100));tips[i] = imageView;if (i == 0) {tips[i].setBackgroundResource(R.drawable.heart);} else {tips[i].setBackgroundResource(R.drawable.ie_arrow_normal);}viewGroup.addView(imageView);}// 设置适配器viewpager.setAdapter(new MyAdapter(list, this));viewpager.setOnPageChangeListener(new OnPageChangeListener(){public void onPageSelected(int arg0) {setImageBackground(arg0 % bitmaps.length);}public void onPageScrolled(int arg0, float arg1, int arg2) {}public void onPageScrollStateChanged(int arg0) {}});// 第一次初始化界面时，显示的界面// 设置ViewPager的默认项, 设置为长度的100倍，这样子开始就能往左滑动viewpager.setCurrentItem((bitmaps.length) * 100);}/** * 设置选中的tip的背景 ，选中哪个图片，哪个图片的点点就变成白的 */private void setImageBackground(int selectItems){for (int i = 0; i < tips.length; i++){if (i == selectItems) {tips[i].setBackgroundResource(bitmaps[i]);} else{tips[i].setBackgroundResource(bitmaps[i]&R.drawable.heart);}}}}

MyAdapter类：

package com.example.android_005_viewpager;import java.util.List;import android.content.Context;import android.support.v4.view.PagerAdapter;import android.view.View;import android.view.ViewGroup;import android.widget.ImageView;public class MyAdapter extends PagerAdapter { private List<ImageView> list; private Context context; public MyAdapter (  List<ImageView> list, Context context) {  super();  this.list = list;  this.context = context; } //该方法将返回所包含的item总个数。为了实现一种循环滚动的效果，返回了基本整形的最大值 @Override public int getCount() {  return Integer.MAX_VALUE; }//判断出去的view是否等于进来的view，如果为true直接复用 @Override public boolean isViewFromObject(View arg0, Object arg1) {  return arg0==arg1; }  //销毁预加载以外的view对象，会把需要销毁的对象的索引位置传进来，就是position，y //因为imageView只要6条数据，而position会取到很大的值，所以使用取余数的方法来获取每一条数据项 @Override public void destroyItem(ViewGroup container, int position, Object object) {  container.removeView(list.get(position%list.size())); } //装入图片 @Override public Object instantiateItem(ViewGroup container, final int position) {  final ImageView imageView = list.get(position % list.size());  container.addView(list.get(position%list.size()),0);  return list.get(position%list.size()); }}

运行结果如下，拨动图片能够实现一起移动：

Android中使用ViewPager实现图片的切换_第1张图片

图片的移动

以上就是ViewPager实现图片切换的步骤

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