效果圖：
大家在寫項目的過程中經常會碰到需要實現Viewpager裏面加載幾張圖片來循環自動輪播的效果，如果不封裝一下的話代碼分散在activity裏面會顯得很亂，而且也不利於我們下次複用，所以這裏我把viewpager的相關代碼抽取出來放在了一個類裏面，使用的時候只需要new 這個對象即可。直接看代碼：
MyViewPager.java類：在activity中只需要在初始化數據的時候加入MyViewPager myViewPager=new MyViewPager(this)這段代碼就ok。
package com.duora.bobge.duoradeliverly_version2.custom_view;
import android.app.Activity;
import android.os.Handler;
import android.os.Message;
import android.support.v4.view.ViewPager;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;
import android.widget.LinearLayout;
import com.duora.bobge.duoradeliverly_version2.R;
import com.duora.bobge.duoradeliverly_version2.adapter.EventPageAdapter;
import com.duora.bobge.duoradeliverly_version2.base.BaseConfig;
import com.duora.bobge.duoradeliverly_version2.listener.NavigationPageChangeListener;
import java.util.ArrayList;
/**
* Created by bobge on 15/8/10.
*/
public class MyViewPager {
private Activity activity;
private ViewPager viewPager;
private LinearLayout mViewPoints;
private ArrayList<View> pageViews;
private ImageView imageView;
/** 將小圓點的圖片用數組表示 */
private ImageView[] imageViews;
private Handler mHandler = new Handler() {
@Override
public void dispatchMessage(Message msg) {
switch (msg.what) {
case BaseConfig.MSG_CHANGE_PHOTO:
int index = viewPager.getCurrentItem();
viewPager.setCurrentItem(index + 1);
mHandler.sendEmptyMessageDelayed(BaseConfig.MSG_CHANGE_PHOTO,
BaseConfig.PHOTO_CHANGE_TIME);
break;
}
super.dispatchMessage(msg);
}
};
public MyViewPager(Activity activity) {
this.activity = activity;
findViewById(activity);
addData();
initPoint();
}
private void addData() {
pageViews = new ArrayList<View>();
for (int i = 0; i < 5; i++) {
ImageView imageView = new ImageView(activity);
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
//picasso加載圖片
switch (i){
case 0:
imageView.setBackgroundResource(R.mipmap.a);
break;
case 1:
imageView.setBackgroundResource(R.mipmap.b);
break;
case 2:
imageView.setBackgroundResource(R.mipmap.c);
break;
case 3:
imageView.setBackgroundResource(R.mipmap.e);
break;
case 4:
imageView.setBackgroundResource(R.mipmap.f);
break;
}
pageViews.add(imageView);
}
}
private void findViewById(Activity activity) {
this.viewPager= (ViewPager)activity.findViewById(R.id.viewPager_main);
this.mViewPoints= (LinearLayout)activity.findViewById(R.id.viewGroup);
}
//創建viewpager的那幾個滑動的點
private void initPoint() {
// 創建imageviews數組，大小是要顯示的圖片的數量
imageViews = new ImageView[pageViews.size()];
// 添加小圓點的圖片
for (int i = 0; i < pageViews.size(); i++) {
imageView = new ImageView(activity);
// 設置小圓點imageview的參數
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
20, 20);
layoutParams.setMargins(5, 0, 5, 0);
imageView.setLayoutParams(layoutParams);// 創建一個寬高均爲20 的佈局
// 將小圓點layout添加到數組中
imageViews[i] = imageView;
// 默認選中的是第一張圖片，此時第一個小圓點是選中狀態，其他不是
if (i == 0) {
imageViews[i]
.setBackgroundResource(R.mipmap.face_float_icon_on);
} else {
imageViews[i]
.setBackgroundResource(R.mipmap.face_float_icon);
}
// 將imageviews添加到小圓點視圖組
mViewPoints.addView(imageViews[i]);
}
// 設置viewpager的適配器和監聽事件
Log.i("test", pageViews.size() + "====");
viewPager.setAdapter(new EventPageAdapter(pageViews));
viewPager.setOnPageChangeListener(new NavigationPageChangeListener(pageViews, imageViews));
viewPager.setCurrentItem((pageViews.size()) * 50);
if(pageViews.size()>1){
mHandler.sendEmptyMessageDelayed(BaseConfig.MSG_CHANGE_PHOTO, BaseConfig.PHOTO_CHANGE_TIME);
}
}
}它的滑動監聽和適配器：
NavigationPageChangeListener.java看命名應該就能知道這個類的作用了，不多說。
package com.duora.bobge.duoradeliverly_version2.listener;
import android.support.v4.view.ViewPager;
import android.view.View;
import android.widget.ImageView;
import com.duora.bobge.duoradeliverly_version2.R;
import java.util.ArrayList;
/**
* Created by bobge on 15/8/5.
*/
//viewpager滑動監聽
public class NavigationPageChangeListener implements ViewPager.OnPageChangeListener {
private ArrayList<View> pageViews;
/** 將小圓點的圖片用數組表示 */
private ImageView[] imageViews;
public NavigationPageChangeListener(ArrayList<View> pageViews, ImageView[] imageViews) {
this.pageViews=pageViews;
this.imageViews=imageViews;
}
@Override
public void onPageScrollStateChanged(int arg0) {
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
@Override
public void onPageSelected(int position) {
//當頁面切換時設置導航點的狀態
setPointStatus(position);
}
//設置導航點的狀態
private void setPointStatus(int position) {
position=position%pageViews.size();
for (int i = 0; i < imageViews.length; i++) {
imageViews[position]
.setBackgroundResource(R.mipmap.face_float_icon_on);
// 不是當前選中的page，其小圓點設置爲未選中的狀態
if (position != i) {
imageViews[i]
.setBackgroundResource(R.mipmap.face_float_icon);
}
}
}
}package com.duora.bobge.duoradeliverly_version2.adapter;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.View;
import java.util.ArrayList;
/**
* Created by bobge on 15/7/30.
*/
public class EventPageAdapter extends PagerAdapter {
private ArrayList<View> pageViews;
public EventPageAdapter(ArrayList<View> pageViews) {
this.pageViews=pageViews;
}
// 銷燬position位置的界面
@Override
public void destroyItem(View container, int position, Object object) {
((ViewPager) container).removeView(pageViews.get(position%pageViews.size()));
}
// 獲取當前窗體界面數
@Override
public int getCount() {
return Integer.MAX_VALUE;
}
// 初始化position位置的界面
@Override
public Object instantiateItem(View v, int position) {
try{
//((ViewPager) arg0).addView(list.get(arg1),0);
((ViewPager) v).addView((View)pageViews.get(position%pageViews.size()),0);
}catch (Exception e) {
// TODO: handle exception
}
return pageViews.get(position%pageViews.size());
}
@Override
public boolean isViewFromObject(View v, Object arg1) {
return v == arg1;
}
@Override
public void startUpdate(View arg0) {
}
@Override
public int getItemPosition(Object object) {
return super.getItemPosition(object);
}
}
佈局：custom_viewpager.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!--帶導航點的viewpager佈局-->
<android.support.v4.view.ViewPager
android:id="@+id/viewPager_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
<LinearLayout
android:id="@+id/viewGroup"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="20dp"
android:gravity="center_horizontal"
android:orientation="horizontal" >
</LinearLayout>
</RelativeLayout>在activity的佈局中只需要導入上面那個佈局即可：
<include layout="@layout/custom_viewpager" android:id="@+id/myViewPager" android:layout_width="match_parent" android:layout_height="@dimen/viewpager_height" />