首先我們需要一個主佈局文件activity_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" >
<android.support.v4.view.ViewPager
android:id="@+id/vp_ad"
android:layout_width="match_parent"
android:layout_height="200dp" >
</android.support.v4.view.ViewPager>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignBottom="@id/vp_ad"
android:background="#77000000"
android:orientation="vertical"
android:padding="8dp" >
<TextView
android:id="@+id/tv_ad"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:ellipsize="end"
android:singleLine="true"
android:text="我是文本"
android:textColor="#fff" />
<LinearLayout
android:id="@+id/dot_layout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_marginTop="3dp"
android:orientation="horizontal" >
</LinearLayout>
</LinearLayout>
</RelativeLayout>
創建了一個類 Ad.java
package com.xuhao.ad;
public class Ad {
private int icon;
private String desc;
public Ad(int icon, String desc) {
super();
this.icon = icon;
this.desc = desc;
}
public int getIcon() {
return icon;
}
public void setIcon(int icon) {
this.icon = icon;
}
public String getDesc() {
return desc;
}
public void setDesc(String desc) {
this.desc = desc;
}
}
接着就是mainactivity裏面主要的功能實現了:
package com.xuhao.ad;
import java.util.ArrayList;
import java.util.List;
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.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.LinearLayout.LayoutParams;
import android.widget.TextView;
public class MainActivity extends Activity {
private ViewPager vpad;
private TextView tv;
private List<Ad> list = new ArrayList<Ad>();
private LinearLayout dot_layout;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
initView();
initListener();
initData();
}
private void initView() {
setContentView(R.layout.activity_main);
vpad = (ViewPager) findViewById(R.id.vp_ad);
tv = (TextView) findViewById(R.id.tv_ad);
dot_layout = (LinearLayout) findViewById(R.id.dot_layout);
}
private void initListener() {
vpad.setOnPageChangeListener(new OnPageChangeListener() {
@Override
public void onPageSelected(int arg0) {
updateDocInfo();
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
@Override
public void onPageScrollStateChanged(int arg0) {
}
});
}
private void initData() {
list.add(new Ad(R.drawable.a, "鞏俐不低俗,我就不能低俗"));
list.add(new Ad(R.drawable.b, "朴樹又回來了,再唱經典老歌引百萬人同唱啊"));
list.add(new Ad(R.drawable.c, "揭祕北京電影如何升級"));
list.add(new Ad(R.drawable.d, "樂視網TV版大放送"));
list.add(new Ad(R.drawable.e, "熱血屌絲的反殺"));
initDots();
vpad.setAdapter(new MyPagerAdapter());
int c=(Integer.MAX_VALUE/2)%list.size();
vpad.setCurrentItem(Integer.MAX_VALUE/2-c);
updateDocInfo();
}
/**
* 初始化點
*/
private void initDots() {
for (int i = 0; i < list.size(); i++) {
View view = new View(this);
LayoutParams layoutParams = new LayoutParams(8, 8);
if (i != 0) {
layoutParams.leftMargin = 5;
}
view.setLayoutParams(layoutParams);
view.setBackgroundResource(R.drawable.selector_dot);
dot_layout.addView(view);
}
}
/**
* 更新文本以及點
*/
private void updateDocInfo() {
int currentItem = vpad.getCurrentItem();
int value=currentItem%list.size();
tv.setText(list.get(value).getDesc());
for (int i = 0; i < dot_layout.getChildCount(); i++) {
dot_layout.getChildAt(i).setEnabled(i==value);
}
}
private class MyPagerAdapter extends PagerAdapter {
@Override
public int getCount() {
return Integer.MAX_VALUE;
}
@Override
public boolean isViewFromObject(View view, Object object) {
return view == object;
}
/**
* 相當於baseadpater中的getview()
*/
@Override
public Object instantiateItem(ViewGroup container, int position) {
View view = View.inflate(MainActivity.this, R.layout.activity_ad,
null);
ImageView im = (ImageView) view.findViewById(R.id.iv);
Ad ad = list.get(position%list.size());
im.setImageResource(ad.getIcon());
container.addView(view);
return view;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
// super.destroyItem(container, position, object);
container.removeView((View) object);
}
}
}
viewpager添加的一個視圖activity_ad.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ImageView
android:id="@+id/iv"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="fitXY"
android:src="@drawable/a" />
</LinearLayout>