初识ViewPager【Android】

viewpager可以实现gallery的图片展示效果

java代码:

package com.succ7.viewpagertest;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.view.Window;import android.widget.ImageView;import android.widget.TextView;import android.widget.Toast;public class MainActivity extends Activity {private ViewPager viewpager;@Overrideprotected void onCreate(Bundle savedInstanceState) {requestWindowFeature(Window.FEATURE_NO_TITLE);super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);viewpager = (ViewPager) findViewById(R.id.viewpager);/*List<ImageView> lists = new ArrayList<ImageView>();ImageView imageView1 = new ImageView(this);imageView1.setBackgroundResource(R.drawable.g1);ImageView imageView2 = new ImageView(this);imageView2.setBackgroundResource(R.drawable.g2);ImageView imageView3 = new ImageView(this);imageView3.setBackgroundResource(R.drawable.g3);ImageView imageView4 = new ImageView(this);imageView4.setBackgroundResource(R.drawable.g4);*//*********************换成textview可以吗******************************/List<TextView> lists = new ArrayList<TextView>();TextView imageView1 = new TextView(this);imageView1.setBackgroundResource(R.drawable.g1);TextView imageView2 = new TextView(this);imageView2.setBackgroundResource(R.drawable.g2);TextView imageView3 = new TextView(this);imageView3.setBackgroundResource(R.drawable.g3);TextView imageView4 = new TextView(this);imageView4.setBackgroundResource(R.drawable.g4);lists.add(imageView1);lists.add(imageView2);lists.add(imageView3);lists.add(imageView4);ViewPagerAdapter adapter = new ViewPagerAdapter(lists);viewpager.setAdapter(adapter);viewpager.setOnPageChangeListener(new OnPageChangeListener() {@Overridepublic void onPageSelected(int arg0) {System.out.println("onPageSelected");Toast.makeText(MainActivity.this, arg0+"", 0).show();}@Overridepublic void onPageScrolled(int arg0, float arg1, int arg2) {System.out.println("onPageScrolled");Toast.makeText(MainActivity.this, arg0+"|"+arg1+"|"+arg2, 0).show();}@Overridepublic void onPageScrollStateChanged(int arg0) {System.out.println("onPageScrollStateChanged");Toast.makeText(MainActivity.this, arg0+"", 0).show();}});}class ViewPagerAdapter extends PagerAdapter {private List<TextView> lists;public ViewPagerAdapter(List<TextView> lists) {this.lists = lists;}@Overridepublic void destroyItem(ViewGroup container, int position, Object object) {((ViewPager) container).removeView(lists.get(position));}@Overridepublic Object instantiateItem(ViewGroup container, int position) {((ViewPager) container).addView(lists.get(position));return lists.get(position);}@Overridepublic int getCount() {return lists.size();}@Overridepublic boolean isViewFromObject(View arg0, Object arg1) {return arg0 == arg1;}}}

Xml布局文件:

<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"    tools:context=".MainActivity" >    <android.support.v4.view.ViewPager        android:id="@+id/viewpager"        android:layout_width="match_parent"        android:layout_height="match_parent" /></RelativeLayout>

使用

android.support.v4.view.ViewPager;

用ImageView 和 TextView都是可以的,只要设置背景图片

imageview 的
setBackgroundResource(resId)设置的是imageview的大小
setImageResource(resId)设置的是图片的实际的大小,相当于

布局文件中的 android:src = "resid"
注意:图片的大小未必是imageview的大小

布局文件: