Android实现图片轮显效果——自定义ViewPager控件

   // 适配器      public  class  MyPagerAdapter  extends PagerAdapter {          private Activity mActivity; // 上下文          private List<View> mListViews; // 图片组          public MyPagerAdapter(){          }          public MyPagerAdapter(Activity mActivity,List<View> mListViews){              this.mActivity=mActivity;              this.mListViews=mListViews;          }          public int getCount() {              if (mListViews.size() == 1) {// 一张图片时不用流动                  return mListViews.size();              }              return Integer.MAX_VALUE;          }          /**              返回List中的图片元素装载到控件中  */          public Object instantiateItem(View v, int i) {              if (((ViewPager) v).getChildCount() == mListViews.size()) {                  ((ViewPager) v)                          .removeView(mListViews.get(i % mListViews.size()));              }              ((ViewPager) v).addView(mListViews.get(i % mListViews.size()), 0);              return mListViews.get(i % mListViews.size());          }            public boolean isViewFromObject(View arg0, Object arg1) {              return arg0 == (arg1);          }            public void destroyItem(ViewGroup view, int i, Object object) {              view.removeView(mListViews.get(i%mListViews.size()));          }                }

public class MyImgScroll extends ViewPager {      Activity mActivity; // 上下文      List<View> mListViews; // 图片组      int mScrollTime = 0;      Timer timer;      int oldIndex = 0;      int curIndex = 0;        public MyImgScroll(Context context, AttributeSet attrs) {          super(context, attrs);      }        /**       * 开始广告滚动       *        * @param mainActivity       *            显示广告的主界面       * @param imgList       *            图片列表, 不能为null ,最少一张       * @param scrollTime       *            滚动间隔 ,0为不滚动       * @param ovalLayout       *            圆点容器,可为空,LinearLayout类型       * @param ovalLayoutId       *            ovalLayout为空时 写0, 圆点layout XMl       * @param ovalLayoutItemId       *            ovalLayout为空时 写0,圆点layout XMl 圆点XMl下View ID       * @param focusedId       *            ovalLayout为空时 写0, 圆点layout XMl 选中时的动画       * @param normalId       *            ovalLayout为空时 写0, 圆点layout XMl 正常时背景       */      public void start(Activity mainActivity, List<View> imgList,              int scrollTime, LinearLayout ovalLayout, int ovalLayoutId,              int ovalLayoutItemId, int focusedId, int normalId) {          mActivity = mainActivity;          mListViews = imgList;          mScrollTime = scrollTime;          // 设置圆点          setOvalLayout(ovalLayout, ovalLayoutId, ovalLayoutItemId, focusedId,                  normalId);          this.setAdapter(new MyPagerAdapter(mActivity,mListViews));// 设置适配器          if (scrollTime != 0 && imgList.size() > 1) {              // 设置滑动动画时间  ,如果用默认动画时间可不用 ,反射技术实现               new FixedSpeedScroller(mActivity).setDuration(this, 700);              startTimer();              // 触摸时停止滚动              this.setOnTouchListener(new OnTouchListener() {                  public boolean onTouch(View v, MotionEvent event) {                      if (event.getAction() == MotionEvent.ACTION_UP) {                          startTimer();                      } else {                          stopTimer();                      }                      return false;                  }              });          }           if (mListViews.size() > 1) {              this.setCurrentItem((Integer.MAX_VALUE / 2)                      - (Integer.MAX_VALUE / 2) % mListViews.size());// 设置选中为中间/图片为和第0张一样          }      }        // 设置圆点      private void setOvalLayout(final LinearLayout ovalLayout, int ovalLayoutId,              final int ovalLayoutItemId, final int focusedId, final int normalId) {          if (ovalLayout != null) {              LayoutInflater inflater=LayoutInflater.from(mActivity);              for (int i = 0; i < mListViews.size(); i++) {                  ovalLayout.addView(inflater.inflate(ovalLayoutId, null));                                }              //选中第一个              ovalLayout.getChildAt(0).findViewById(ovalLayoutItemId)              .setBackgroundResource(focusedId);              this.setOnPageChangeListener(new OnPageChangeListener() {                  public void onPageSelected(int i) {                      curIndex = i % mListViews.size();                      //取消圆点选中                      ovalLayout.getChildAt(oldIndex).findViewById(ovalLayoutItemId)                              .setBackgroundResource(normalId);                       //圆点选中                      ovalLayout.getChildAt(curIndex).findViewById(ovalLayoutItemId)                      .setBackgroundResource(focusedId);                      oldIndex = curIndex;                  }                    public void onPageScrolled(int arg0, float arg1, int arg2) {                  }                    public void onPageScrollStateChanged(int arg0) {                  }              });          }      }      /**       * 取得当明选中下标       * @return       */      public int getCurIndex() {          return curIndex;      }      /**       * 停止滚动       */      public void stopTimer() {          if (timer != null) {              timer.cancel();              timer = null;          }      }        /**       * 开始滚动       */      public void startTimer() {          timer = new Timer();          timer.schedule(new TimerTask() {              public void run() {                  mActivity.runOnUiThread(new Runnable() {                      public void run() {                          MyImgScroll.this.setCurrentItem(MyImgScroll.this                                  .getCurrentItem() + 1);//设置控件当前项（改变图片）                      }                  });              }          }, mScrollTime, mScrollTime);      }    }

package com.tianshicoffeeom.app.imgscroll;  import java.lang.reflect.Field;  import android.content.Context;  import android.support.v4.view.ViewPager;  import android.view.animation.Interpolator;  import android.widget.Scroller;   /**    * 图片滑动动画时间控制类  , 如果采用默认时间可不用这个类 ,通过反射技术改变ViewPager的滑动时间    *    */  public class FixedSpeedScroller extends Scroller {        private Context context;      private int mDuration = 500;        public FixedSpeedScroller(Context context) {            super(context);            this.context=context;      }        public FixedSpeedScroller(Context context, Interpolator interpolator) {            super(context, interpolator);            this.context=context;      }       /**       *  设置改变ViewPager的滑动时间         * @param vp  ViewPager 对象       * @param time  时间       */      public void setDuration(ViewPager vp,int time) {           try {               Field field = ViewPager.class.getDeclaredField("mScroller");               field.setAccessible(true);               this.setmDuration(time);//设置翻动时间               field.set(vp, this);           } catch (Exception e) {             }       }       @Override        public void startScroll(int startX, int startY, int dx, int dy, int duration) {            //System.out.println("startScroll1");          super.startScroll(startX, startY, dx, dy, mDuration);        }        @Override        public void startScroll(int startX, int startY, int dx, int dy) {            //System.out.println("startScroll2");          super.startScroll(startX, startY, dx, dy, mDuration);        }        public void setmDuration(int time) {            mDuration = time;        }        public int getmDuration() {            return mDuration;        }    }

public class MainActivity extends Activity {            private MyImgScroll myPager; // 图片容器      private LinearLayout ovalLayout; // 圆点容器      private List<View> listViews; // 图片组      @Override      public void onCreate(Bundle savedInstanceState) {          super.onCreate(savedInstanceState);          setContentView(R.layout.activity_main);          myPager = (MyImgScroll) findViewById(R.id.myvp);          ovalLayout = (LinearLayout) findViewById(R.id.vb);          InitViewPager();//初始化图片          //开始滚动          myPager.start(this, listViews, 4000, ovalLayout,                  R.layout.ad_bottom_item, R.id.ad_item_v,                  R.drawable.dot_focused, R.drawable.dot_normal);      }      @Override      protected void onRestart() {          myPager.startTimer();          super.onRestart();      }            @Override      protected void onStop() {          myPager.stopTimer();          super.onStop();      }      /**       * 初始化图片       */      private void InitViewPager() {          listViews = new ArrayList<View>();          int[] imageResId = new int[] { R.drawable.banner1, R.drawable. banner2,                  R.drawable. banner3, R.drawable.d, R.drawable. banner4 };          for (int i = 0; i < imageResId.length; i++) {              ImageView imageView = new ImageView(this);              imageView.setOnClickListener(new OnClickListener() {                  public void onClick(View v) {// 设置图片点击事件                      Toast.makeText(MainActivity.this,                              "点击了:" + myPager.getCurIndex(), Toast.LENGTH_SHORT)                              .show();                  }              });              imageView.setImageResource(imageResId[i]);              imageView.setScaleType(ScaleType.CENTER_CROP);              listViews.add(imageView);          }      }    }

<LinearLayout 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:orientation="vertical" >      <com.jereh.view. MyScrollImageView          android:id="@+id/myvp"          android:layout_width="fill_parent"          android:layout_height="120dp" />      <LinearLayout          android:id="@+id/vb"          android:layout_width="match_parent"          android:layout_height="10dp"          android:layout_marginTop="3dip"          android:gravity="center"          android:orientation="horizontal" >      </LinearLayout>  </LinearLayout>