首先给大家展示靓照，对效果图感兴趣的朋友可以继续往下阅读哦。
viewpager这个小demo实现的是可以左右循环滑动图片，下面带索引，滑到最后一页在往右滑动就要第一页，第一页往左滑动就到最后一页，上面是效果图，用美女图片是我一贯的作风，呵呵
1. 首先看一些layout下的xml
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
|
<framelayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<android.support.v4.view.viewpager
android:id="@+id/viewpager"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<relativelayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<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>
</relativelayout>
</framelayout>
|
使用viewpager首先需要引入android-support-v4.jar这个jar包。自己不要忘记加
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
package com.example.viewpagerdemo;
import android.app.activity;
import android.os.bundle;
import android.support.v4.view.pageradapter;
import android.support.v4.view.viewpager;
import android.support.v4.view.viewpager.onpagechangelistener;
import android.view.view;
import android.view.viewgroup;
import android.view.viewgroup.layoutparams;
import android.widget.imageview;
import android.widget.linearlayout;
public class twoactivity extends activity implements onpagechangelistener{
/**
* viewpager
*/
private viewpager viewpager;
/**
* 装点点的imageview数组
*/
private imageview[] tips;
/**
* 装imageview数组
*/
private imageview[] mimageviews;
/**
* 图片资源id
*/
private int[] imgidarray ;
@override
protected void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);
setcontentview(r.layout.activity_main);
viewgroup group = (viewgroup)findviewbyid(r.id.viewgroup);
viewpager = (viewpager) findviewbyid(r.id.viewpager);
//载入图片资源id
imgidarray = new int[]{r.drawable.item01, r.drawable.item02, r.drawable.item03, r.drawable.item04,
r.drawable.item05,r.drawable.item06, r.drawable.item07, r.drawable.item08};
//将点点加入到viewgroup中
tips = new imageview[imgidarray.length];
for(int i=0; i<tips.length; i++){
imageview imageview = new imageview(this);
imageview.setlayoutparams(new layoutparams(10,10));
tips[i] = imageview;
if(i == 0){
tips[i].setbackgroundresource(r.drawable.page_indicator_focused);
}else{
tips[i].setbackgroundresource(r.drawable.page_indicator_unfocused);
}
linearlayout.layoutparams layoutparams = new linearlayout.layoutparams(new viewgroup.layoutparams(layoutparams.wrap_content,
layoutparams.wrap_content));
layoutparams.leftmargin = 5;
layoutparams.rightmargin = 5;
group.addview(imageview, layoutparams);
}
//将图片装载到数组中
mimageviews = new imageview[imgidarray.length];
for(int i=0; i<mimageviews.length; i++){
imageview imageview = new imageview(this);
mimageviews[i] = imageview;
imageview.setbackgroundresource(imgidarray[i]);
}
//设置adapter
viewpager.setadapter(new myadapter());
//设置监听，主要是设置点点的背景
viewpager.setonpagechangelistener(this);
//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((mimageviews.length) * 100);
}
/**
*
* @author xiaanming
*
*/
public class myadapter extends pageradapter{
@override
public int getcount() {
return integer.max_value;
}
@override
public boolean isviewfromobject(view arg0, object arg1) {
return arg0 == arg1;
}
@override
public void destroyitem(view container, int position, object object) {
((viewpager)container).removeview(mimageviews[position % mimageviews.length]);
}
/**
* 载入图片进去，用当前的position 除以 图片数组长度取余数是关键
*/
@override
public object instantiateitem(view container, int position) {
((viewpager)container).addview(mimageviews[position % mimageviews.length], 0);
return mimageviews[position % mimageviews.length];
}
}
@override
public void onpagescrollstatechanged(int arg0) {
}
@override
public void onpagescrolled(int arg0, float arg1, int arg2) {
}
@override
public void onpageselected(int arg0) {
setimagebackground(arg0 % mimageviews.length);
}
/**
* 设置选中的tip的背景
* @param selectitems
*/
private void setimagebackground(int selectitems){
for(int i=0; i<tips.length; i++){
if(i == selectitems){
tips[i].setbackgroundresource(r.drawable.page_indicator_focused);
}else{
tips[i].setbackgroundresource(r.drawable.page_indicator_unfocused);
}
}
}
}
|
喜欢的朋友直接下载代码哦。代码下载
上面的代码中，当只有3张图片或者2张图片的时候，滑动存在bug问题的修改如下
destroyitem(view container, int position, object object)方法中不removeview
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
|
@override
public void destroyitem(view container, int position, object object) {
// ((viewpager)container).removeview(mimageviews[position % mimageviews.length]);
}
instantiateitem(view container, int position)增加异常扑捉
[java] view plaincopy在code上查看代码片派生到我的代码片
@override
public object instantiateitem(view container, int position) {
try {
((viewpager)container).addview(mimageviews[position % mimageviews.length], 0);
}catch(exception e){
//handler something
}
return mimageviews[position % mimageviews.length];
}
|
以上代码给大家展示了android 利用viewpager实现图片可以左右循环滑动效果，希望大家喜欢。