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Android客户端图片左右滑动切换 Android开发实现高仿优酷的客户端图片左右滑动切换功能实例【附源码下载】

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本文实例讲述了Android开发实现高仿优酷的客户端图片左右滑动切换功能。分享给大家供大家参考，具体如下：

本例是用ViewPager去做的实现，支持自动滑动和手动滑动，不仅优酷网，实际上有很多商城和门户网站都有类似的实现:

具体思路：

1. 工程中需要添加android-support-v4.jar,才能使用ViewPager控件.

2. 图片的自动切换: 可使用Timer或者ScheduledExecutorService,这个有多重方式可以实现.
同时要切换底部的dots（园点）

3.Handler+Message机制更新UI,这个相信大家都很熟练，不再描述

4. 实现的一些细节:注意本例中的优化：图片的自动切换启动了其他的线程，要在Activity在可见到不可见的状态,也就是在onStop()方法中将线程停止，在onStart()方法中开启线程。否则，Timer没有停止，或者反复开启，会引起较大的内存消耗，时间一长就程序就会崩掉。 还有，就是在跳转到其他Activity的过程中会出现画面的卡顿

下面看一下效果图和具体代码:

工程结构如下图所示：

main.xml:

然后是具体的布局文件及代码实现:

main.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:background="#FFFFFF"
  android:orientation="vertical" >
  <RelativeLayout
    android:layout_width="fill_parent"
    android:layout_height="40dip"
    android:background="@drawable/title_bk" >
    <ImageButton
      android:id="@+id/btn_back"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:background="@drawable/btn_back_selector"
      android:src="@drawable/btn_back" />
    <View
      android:id="@+id/line0"
      android:layout_width="1px"
      android:layout_height="fill_parent"
      android:layout_toRightOf="@id/btn_back"
      android:background="#aa11264f" />
    <View
      android:layout_width="1px"
      android:layout_height="fill_parent"
      android:layout_toRightOf="@id/line0"
      android:background="#009ad6" />
    <TextView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_centerInParent="true"
      android:text="优酷客户端"
      android:textColor="#FFFFFF"
      android:textSize="20sp" />
  </RelativeLayout>
  <FrameLayout
    android:layout_width="fill_parent"
    android:layout_height="140dip" >
    <android.support.v4.view.ViewPager
      android:id="@+id/vp"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent" />
    <LinearLayout
      android:layout_width="fill_parent"
      android:layout_height="35dip"
      android:layout_gravity="bottom"
      android:background="#33000000"
      android:gravity="center"
      android:orientation="vertical" >
      <TextView
        android:id="@+id/tv_title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="中国家庭院校园区域名字体现"
        android:textColor="#ffffff" />
      <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="3dip"
        android:gravity="center" >
        <View
          android:id="@+id/v_dot0"
          style="@style/dot_style"
          android:background="@drawable/dot_focused" />
        <View
          android:id="@+id/v_dot1"
          style="@style/dot_style" />
        <View
          android:id="@+id/v_dot2"
          style="@style/dot_style" />
        <View
          android:id="@+id/v_dot3"
          style="@style/dot_style" />
        <View
          android:id="@+id/v_dot4"
          style="@style/dot_style" />
      </LinearLayout>
    </LinearLayout>
  </FrameLayout>
</LinearLayout>

MyViewPagerActivity:

package com.tony.viewpager;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Parcelable;
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.widget.ImageView;
import android.widget.ImageView.ScaleType;
import android.widget.TextView;
/**
 * 仿优酷Android客户端图片左右滑动
 *
 */
public class MyViewPagerActivity extends Activity {
  private ViewPager viewPager; // android-support-v4中的滑动组件
  private List<ImageView> imageViews; // 滑动的图片集合
  private String[] titles; // 图片标题
  private int[] imageResId; // 图片ID
  private List<View> dots; // 图片标题正文的那些点
  private TextView tv_title;
  private int currentItem = 0; // 当前图片的索引号
  // An ExecutorService that can schedule commands to run after a given delay,
  // or to execute periodically.
  private ScheduledExecutorService scheduledExecutorService;
  // 切换当前显示的图片
  private Handler handler = new Handler() {
    public void handleMessage(android.os.Message msg) {
      viewPager.setCurrentItem(currentItem);// 切换当前显示的图片
    };
  };
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    imageResId = new int[] { R.drawable.a, R.drawable.b, R.drawable.c, R.drawable.d, R.drawable.e };
    titles = new String[imageResId.length];
    titles[0] = "巩俐不低俗，我就不能低俗";
    titles[1] = "扑树又回来啦！再唱经典老歌引万人大合唱";
    titles[2] = "揭秘北京电影如何升级";
    titles[3] = "乐视网TV版大派送";
    titles[4] = "热血屌丝的反杀";
    imageViews = new ArrayList<ImageView>();
    // 初始化图片资源
    for (int i = 0; i < imageResId.length; i++) {
      ImageView imageView = new ImageView(this);
      imageView.setImageResource(imageResId[i]);
      imageView.setScaleType(ScaleType.CENTER_CROP);
      imageViews.add(imageView);
    }
    dots = new ArrayList<View>();
    dots.add(findViewById(R.id.v_dot0));
    dots.add(findViewById(R.id.v_dot1));
    dots.add(findViewById(R.id.v_dot2));
    dots.add(findViewById(R.id.v_dot3));
    dots.add(findViewById(R.id.v_dot4));
    tv_title = (TextView) findViewById(R.id.tv_title);
    tv_title.setText(titles[0]);//
    viewPager = (ViewPager) findViewById(R.id.vp);
    viewPager.setAdapter(new MyAdapter());// 设置填充ViewPager页面的适配器
    // 设置一个监听器，当ViewPager中的页面改变时调用
    viewPager.setOnPageChangeListener(new MyPageChangeListener());
  }
  @Override
  protected void onStart() {
    scheduledExecutorService = Executors.newSingleThreadScheduledExecutor();
    // 当Activity显示出来后，每两秒钟切换一次图片显示
    scheduledExecutorService.scheduleAtFixedRate(new ScrollTask(), 1, 2, TimeUnit.SECONDS);
    super.onStart();
  }
  @Override
  protected void onStop() {
    // 当Activity不可见的时候停止切换
    scheduledExecutorService.shutdown();
    super.onStop();
  }
  /**
   * 换行切换任务
   *
   * @author Administrator
   *
   */
  private class ScrollTask implements Runnable {
    public void run() {
      synchronized (viewPager) {
        System.out.println("currentItem: " + currentItem);
        currentItem = (currentItem + 1) % imageViews.size();
        handler.obtainMessage().sendToTarget(); // 通过Handler切换图片
      }
    }
  }
  /**
   * 当ViewPager中页面的状态发生改变时调用
   *
   * @author Administrator
   *
   */
  private class MyPageChangeListener implements OnPageChangeListener {
    private int oldPosition = 0;
    /**
     * This method will be invoked when a new page becomes selected.
     * position: Position index of the new selected page.
     */
    public void onPageSelected(int position) {
      currentItem = position;
      tv_title.setText(titles[position]);
      dots.get(oldPosition).setBackgroundResource(R.drawable.dot_normal);
      dots.get(position).setBackgroundResource(R.drawable.dot_focused);
      oldPosition = position;
    }
    public void onPageScrollStateChanged(int arg0) {
    }
    public void onPageScrolled(int arg0, float arg1, int arg2) {
    }
  }
  /**
   * 填充ViewPager页面的适配器
   *
   * @author Administrator
   *
   */
  private class MyAdapter extends PagerAdapter {
    @Override
    public int getCount() {
      return imageResId.length;
    }
    @Override
    public Object instantiateItem(View arg0, int arg1) {
      ((ViewPager) arg0).addView(imageViews.get(arg1));
      return imageViews.get(arg1);
    }
    @Override
    public void destroyItem(View arg0, int arg1, Object arg2) {
      ((ViewPager) arg0).removeView((View) arg2);
    }
    @Override
    public boolean isViewFromObject(View arg0, Object arg1) {
      return arg0 == arg1;
    }
    @Override
    public void restoreState(Parcelable arg0, ClassLoader arg1) {
    }
    @Override
    public Parcelable saveState() {
      return null;
    }
    @Override
    public void startUpdate(View arg0) {
    }
    @Override
    public void finishUpdate(View arg0) {
    }
  }
}

Drawable目录下

btn_back_selector.xml:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
  <item android:drawable="@drawable/btn_top_pressed" android:state_focused="true"></item>
  <item android:drawable="@drawable/btn_top_pressed" android:state_pressed="true"></item>
  <item android:drawable="@drawable/btn_top_pressed" android:state_selected="true"></item>
  <item android:drawable="@drawable/title_bk"></item>
</selector>

btn_top_pressed.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
  android:shape="rectangle" >
  <gradient
    android:angle="270"
    android:endColor="#009ad6"
    android:startColor="#11264f" />
</shape>

dot_focused.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
  android:shape="oval" >
  <solid android:color="#aaFFFFFF" />
  <corners android:radius="5dip" />
</shape>

dot_normal.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
  android:shape="oval" >
  <solid android:color="#33000000" />
  <corners android:radius="5dip" />
</shape>

title_bk.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
  android:shape="rectangle" >
  <gradient
    android:angle="270"
    android:endColor="#11264f"
    android:startColor="#009ad6" />
</shape>

完整源码点击此处本站下载。

希望本文所述对大家Android程序设计有所帮助。

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