Android实现图片文字轮播特效

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.os.Bundle; import android.app.Activity; 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.ImageView.ScaleType; import android.widget.LinearLayout; import android.widget.TextView;  public class MainActivity extends Activity {    //viewpager   private ViewPager view_pager;   private LinearLayout ll_dotGroup;   private TextView newsTitle;   private int imgResIds[] = new int[]{R.drawable.a, R.drawable.b,       R.drawable.c, R.drawable.d, R.drawable.b};   //存储5张图片   private String textview[]=new String[]{"12412515125","fawfafawf"       ,"13f1f12f211","1251f1f12","1t1f12f121"};   //存储5个目录   private int curIndex = 0;   //用来记录当前滚动的位置   PicsAdapter picsAdapter;    @Override   protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.activity_main);      setViewPager();    }    private void setViewPager() {      newsTitle=(TextView)findViewById(R.id.NewsTitle);     view_pager = (ViewPager) findViewById(R.id.view_pager);     ll_dotGroup = (LinearLayout) findViewById(R.id.dotgroup);      picsAdapter = new PicsAdapter(); // 创建适配器     picsAdapter.setData(imgResIds);     view_pager.setAdapter(picsAdapter); // 设置适配器      view_pager.setOnPageChangeListener(new MyPageChangeListener()); //设置页面切换监听器      initPoints(imgResIds.length); // 初始化图片小圆点     startAutoScroll(); // 开启自动播放   }     // 初始化图片轮播的小圆点和目录   private void initPoints(int count) {     for (int i = 0; i < count; i++) {        ImageView iv = new ImageView(this);       LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(           20, 20);       params.setMargins(0, 0, 20, 0);       iv.setLayoutParams(params);        iv.setImageResource(R.drawable.dot1);        ll_dotGroup.addView(iv);      }     ((ImageView) ll_dotGroup.getChildAt(curIndex))         .setImageResource(R.drawable.dot2);      newsTitle.setText(textview[curIndex]);   }    // 自动播放   private void startAutoScroll() {     ScheduledExecutorService scheduledExecutorService = Executors         .newSingleThreadScheduledExecutor();     // 每隔4秒钟切换一张图片     scheduledExecutorService.scheduleWithFixedDelay(new ViewPagerTask(), 5,         4, TimeUnit.SECONDS);   }    // 切换图片任务   private class ViewPagerTask implements Runnable {     @Override     public void run() {        runOnUiThread(new Runnable() {         @Override         public void run() {           int count = picsAdapter.getCount();           view_pager.setCurrentItem((curIndex + 1) % count);         }       });     }   }    // 定义ViewPager控件页面切换监听器   class MyPageChangeListener implements OnPageChangeListener {      @Override     public void onPageScrolled(int position, float positionOffset,                   int positionOffsetPixels) {     }      @Override     public void onPageSelected(int position) {       ImageView imageView1 = (ImageView) ll_dotGroup.getChildAt(position);       ImageView imageView2 = (ImageView) ll_dotGroup.getChildAt(curIndex);       if (imageView1 != null) {         imageView1.setImageResource(R.drawable.dot2);       }       if (imageView2 != null) {         imageView2.setImageResource(R.drawable.dot1);       }       curIndex = position;       newsTitle.setText(textview[curIndex]);      }       boolean b = false;      @Override     public void onPageScrollStateChanged(int state) {       //这段代码可不加，主要功能是实现切换到末尾后返回到第一张       switch (state) {         case 1:// 手势滑动           b = false;           break;         case 2:// 界面切换中           b = true;           break;         case 0:// 滑动结束，即切换完毕或者加载完毕           // 当前为最后一张，此时从右向左滑，则切换到第一张           if (view_pager.getCurrentItem() == view_pager.getAdapter()               .getCount() - 1 && !b) {             view_pager.setCurrentItem(0);           }           // 当前为第一张，此时从左向右滑，则切换到最后一张           else if (view_pager.getCurrentItem() == 0 && !b) {             view_pager.setCurrentItem(view_pager.getAdapter()                 .getCount() - 1);           }           break;          default:           break;       }     }   }    // 定义ViewPager控件适配器   class PicsAdapter extends PagerAdapter {      private List<ImageView> views = new ArrayList<ImageView>();      @Override     public int getCount() {       if (views == null) {         return 0;       }       return views.size();     }      public void setData(int[] imgResIds) {       for (int i = 0; i < imgResIds.length; i++) {         ImageView iv = new ImageView(MainActivity.this);         ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(             ViewGroup.LayoutParams.MATCH_PARENT,             ViewGroup.LayoutParams.MATCH_PARENT);         iv.setLayoutParams(params);         iv.setScaleType(ScaleType.FIT_XY);         //设置ImageView的属性         iv.setImageResource(imgResIds[i]);         views.add(iv);       }     }      public Object getItem(int position) {       if (position < getCount())         return views.get(position);       return null;     }      @Override     public boolean isViewFromObject(View arg0, Object arg1) {       return arg0 == arg1;     }      @Override     public void destroyItem(View container, int position, Object object) {        if (position < views.size())         ((ViewPager) container).removeView(views.get(position));     }      @Override     public int getItemPosition(Object object) {       return views.indexOf(object);     }      @Override     public Object instantiateItem(View container, int position) {       if (position < views.size()) {         final ImageView imageView = views.get(position);         ((ViewPager) container).addView(imageView);         return views.get(position);       }       return null;     }    }  } 

<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" >    <RelativeLayout     android:layout_width="match_parent"     android:layout_height="150dp"     android:layout_marginBottom="5dp"     android:orientation="vertical" >      <android.support.v4.view.ViewPager       android:id="@+id/view_pager"       android:layout_width="match_parent"       android:layout_height="match_parent"       android:layout_gravity="center" >     </android.support.v4.view.ViewPager>      <RelativeLayout       android:layout_width="match_parent"       android:layout_height="wrap_content"       android:layout_alignParentBottom="true"       android:background="@drawable/focus_bg"       >       <TextView         android:id="@+id/NewsTitle"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:text="我校交换生演讲比赛夺冠 美国华盛本大学万里发来贺电"         android:paddingTop="10dp"         android:paddingBottom="8dp"         android:paddingLeft="10dp"         android:paddingRight="100dp"         android:textSize="15sp"         android:textColor="#fff"/>     <LinearLayout       android:id="@+id/dotgroup"       android:layout_width="wrap_content"       android:layout_height="wrap_content"       android:layout_alignParentRight="true"       android:paddingTop="23dp"       android:paddingRight="10dp"       android:gravity="center"       android:layout_marginBottom="15dp"       android:orientation="horizontal" >     </LinearLayout>   </RelativeLayout>   </RelativeLayout>  </RelativeLayout>