viewPager+Handler+Timer实现广告轮播
基本思想是在 Avtivity 中放一个 ViewPager ，然后通过监听去实现联动效果 , 代码理由详细的解释，我就不说了。
MainActivity.java
1 package com.example.administrator.imageviewlunbodemo;
2
3 import android.app.Activity;
4 import android.os.Bundle;
5 import android.os.Handler;
6 import android.os.Message;
7 import android.support.v4.view.PagerAdapter;
8 import android.support.v4.view.ViewPager;
9 import android.view.LayoutInflater;
10 import android.view.View;
11 import android.view.ViewGroup;
12 import android.widget.ImageView;
13
14 import java.util.ArrayList;
15 import java.util.List;
16 import java.util.Timer;
17 import java.util.TimerTask;
18
19
20 public class MainActivity extends Activity {
21
22 private ViewPager myViewPager;
23 private List<View> myContiontar = new ArrayList<>(); //viewPager的数据源
24 private PagerAdapter myPagerAdapter; //有了数据源，必然要有适配器
25
26 private ImageView imageView1;
27 private ImageView imageView2;
28 private ImageView imageView3;
29 private ImageView imageView4;
30 private ImageView imageView5;
31
32 private Timer mTimer;
33 private Timertask mTimertask;
34
35 @Override
36 protected void onCreate(Bundle savedInstanceState) {
37 super.onCreate(savedInstanceState);
38 setContentView(R.layout.activity_main);
39
40 initViews(); //初始化各种View
41
42 myViewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
43 @Override
44 public void onPageScrolled(int i, float v, int i2) {
45
46 }
47
48 @Override
49 public void onPageSelected(int i) {
50 selectImageId(i);
51 }
52
53 @Override
54 public void onPageScrollStateChanged(int i) {
55
56 }
57 });
58
59 mTimertask = new Timertask();
60 mTimer = new Timer();
61 mTimer.schedule(mTimertask,0,2000);
62 // //启动时选择第一张图片
63 // imageView1.setBackgroundResource(R.drawable.wallet_coin_purse_guide_purse_dot_select);
64
65
66 }
67
68 //初始化各种View
69 private void initViews(){
70 // 先将xml文件 换成 view
71 myViewPager = (ViewPager) findViewById(R.id.viewpager);
72
73 imageView1 = (ImageView) findViewById(R.id.first_fragment_down_image1);
74 imageView2 = (ImageView) findViewById(R.id.first_fragment_down_image2);
75 imageView3 = (ImageView) findViewById(R.id.first_fragment_down_image3);
76 imageView4 = (ImageView) findViewById(R.id.first_fragment_down_image4);
77 imageView5 = (ImageView) findViewById(R.id.first_fragment_down_image5);
78
79 //建立五个view 去获得四个ImageView
80 View view1 = LayoutInflater.from(getApplicationContext()).inflate(R.layout.lunbo_image1, null);
81 View view2 = LayoutInflater.from(getApplicationContext()).inflate(R.layout.lunbo_image2,null);
82 View view3 = LayoutInflater.from(getApplicationContext()).inflate(R.layout.lunbo_image3, null);
83 View view4 = LayoutInflater.from(getApplicationContext()).inflate(R.layout.lunbo_image4, null);
84 View view5 = LayoutInflater.from(getApplicationContext()).inflate(R.layout.lunbo_image5,null);
85 //加入到容器里面
86 myContiontar.add(view1);
87 myContiontar.add(view2);
88 myContiontar.add(view3);
89 myContiontar.add(view4);
90 myContiontar.add(view5);
91 //初始化 适配器
92 myPagerAdapter = new PagerAdapter() {
93 //返回显示多少项
94 @Override
95 public int getCount() {
96 return myContiontar.size();
97 }
98
99 @Override
100 public boolean isViewFromObject(View view, Object o) {
101 return view == o;
102 }
103 //滑动切换时，移除当前组件
104 @Override
105 public void destroyItem(ViewGroup container, int position, Object object) {
106 container.removeView(myContiontar.get(position));
107 }
108 //没次滑动时生成的组件
109 @Override
110 public Object instantiateItem(ViewGroup container, int position) {
111 container.addView(myContiontar.get(position));
112 return myContiontar.get(position);
113 }
114 };
115 //设置适配器
116 myViewPager.setAdapter(myPagerAdapter);
117 }
118
119 //选择那个图片
120 private void selectImageId(int i){
121 initImageBackGround();
122 switch (i){
123 case 0:
124 imageView1.setBackgroundResource(R.drawable.wallet_coin_purse_guide_purse_dot_select);
125 break;
126 case 1:
127 imageView2.setBackgroundResource(R.drawable.wallet_coin_purse_guide_purse_dot_select);
128 break;
129 case 2:
130 imageView3.setBackgroundResource(R.drawable.wallet_coin_purse_guide_purse_dot_select);
131 break;
132 case 3:
133 imageView4.setBackgroundResource(R.drawable.wallet_coin_purse_guide_purse_dot_select);
134 break;
135 case 4:
136 imageView5.setBackgroundResource(R.drawable.wallet_coin_purse_guide_purse_dot_select);
137 break;
138 }
139 }
140 //初始化 所有Image的背景
141 private void initImageBackGround(){
142 imageView1.setBackgroundResource(R.drawable.wallet_coin_purse_guide_purse_dot_normal);
143 imageView2.setBackgroundResource(R.drawable.wallet_coin_purse_guide_purse_dot_normal);
144 imageView3.setBackgroundResource(R.drawable.wallet_coin_purse_guide_purse_dot_normal);
145 imageView4.setBackgroundResource(R.drawable.wallet_coin_purse_guide_purse_dot_normal);
146 imageView5.setBackgroundResource(R.drawable.wallet_coin_purse_guide_purse_dot_normal);
147 }
148
149 int count = 0;
150 private Handler mhandler = new Handler(){
151
152 @Override
153 public void handleMessage(Message msg) {
154 super.handleMessage(msg);
155 if (msg.what == 0x111){
156 //操作
157 count++;
158 myViewPager.setCurrentItem(count % 5);
159 }
160 }
161 };
162
163 //建立一个Timertask
164 class Timertask extends TimerTask{
165
166 @Override
167 public void run() {
168 mhandler.sendEmptyMessage(0x111); //发送空消息
169 }
170 }
171 }
主布局文件里面放了一个 ViewPager 和五个 ImageView （就是那种小点点）
activity_main.xml
<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" tools:context=".MainActivity"> <FrameLayout android:layout_width="match_parent" android:layout_height="0dp" android:layout_weight="1" android:orientation="vertical" android:gravity="center|bottom"> <android.support.v4.view.ViewPager android:id="@+id/viewpager" android:layout_width="match_parent" android:layout_height="match_parent"> </android.support.v4.view.ViewPager> <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginBottom="5dp" android:orientation="horizontal" android:layout_gravity="center|bottom"> <ImageView android:id="@+id/first_fragment_down_image1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="2dp" android:layout_marginRight="2dp" android:background="@drawable/wallet_coin_purse_guide_purse_dot_normal"/> <ImageView android:id="@+id/first_fragment_down_image2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="2dp" android:layout_marginRight="2dp" android:background="@drawable/wallet_coin_purse_guide_purse_dot_normal"/> <ImageView android:id="@+id/first_fragment_down_image3" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="2dp" android:layout_marginRight="2dp" android:background="@drawable/wallet_coin_purse_guide_purse_dot_normal"/> <ImageView android:id="@+id/first_fragment_down_image4" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="2dp" android:layout_marginRight="2dp" android:background="@drawable/wallet_coin_purse_guide_purse_dot_normal"/> <ImageView android:id="@+id/first_fragment_down_image5" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="2dp" android:layout_marginRight="2dp" android:background="@drawable/wallet_coin_purse_guide_purse_dot_normal"/> </LinearLayout> </FrameLayout> <ImageView android:layout_width="match_parent" android:layout_height="0dp" android:layout_weight="2.5" android:background="@color/fitst_fragment_image_color"/> </LinearLayout>
在 ViewPager 中我创建了五个布局文件，都很简单，里面就只有一个 ImageView 去显示图片
images.xml
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <ImageView android:id="@+id/first_fragment_lunbo_image1" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@drawable/image1" /> </LinearLayout>
然后在用 Timer 让它每隔 2 秒去发送一次消息，通知 ViewPager 更新 , 就形成了简单的图片轮播效果。
效果图 :
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