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之前在网上看了很多banner的demo,但是大多是只能自动轮换而不能手动轮换（或者说是最后一张轮换不到第一张）
在参考http://blog.csdn.net/a553181867/article/details/52734261的作品下，我以此为基础做了改进。
好，那我现在就先上图
改进的思想：
然后就是判断当页面1跑到页面5的时候
让第一个页面5跳转到倒数第二的页面5.
主界面xml
<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"><TextViewandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:text="example"android:textSize="24sp"android:layout_marginTop="5dp"android:layout_marginBottom="40dp"/><com.chenyu.library.bannerViewPager.BannerViewPagerandroid:id="@+id/banner"android:layout_width="match_parent"android:layout_height="200dp"></com.chenyu.library.bannerViewPager.BannerViewPager></LinearLayout>
public class BannerViewPager extends FrameLayout implements ViewPager.OnPageChangeListener {private ViewPager mViewPager;private ViewPagerIndicator mIndicator;private ViewPagerAdapter mAdapter;private Context mContext;private int mCurrentPosition;public String TAG = "CJW";public JungeValueChange jungle;public JungeValue jungleValue;public boolean ChangOrNot;//viewpager's rolling stateprivate int mViewPagerScrollState;//by default,auto-rolling is on.private boolean isAutoRolling = true;//the interval between rollingsprivate int mAutoRollingTime = 2000;private int mReleasingTime = 0;private static final int MESSAGE_AUTO_ROLLING = 0X1001;private static final int MESSAGE_AUTO_ROLLING_CANCEL = 0X1002;private static final int MESSAGE_ININTIAL_VIEW = 0X1003;private Handler mHandler = new Handler() {@Overridepublic void handleMessage(Message msg) {switch (msg.what) {case MESSAGE_AUTO_ROLLING:if (mCurrentPosition == mAdapter.getCount() - 2) {mViewPager.setCurrentItem(1, false);} else {mViewPager.setCurrentItem(mCurrentPosition + 1, true);}postDelayed(mAutoRollingTask, mAutoRollingTime);break;case MESSAGE_AUTO_ROLLING_CANCEL:if (mCurrentPosition == mAdapter.getCount() - 1) {mViewPager.setCurrentItem(1, true);} else if (mCurrentPosition == 0) {mViewPager.setCurrentItem(mAdapter.getCount() - 2, true);}post(mAutoRollingTask);break;case MESSAGE_ININTIAL_VIEW:mViewPager.setCurrentItem(1, false);break;}}};public BannerViewPager(Context context) {this(context, null);}public BannerViewPager(Context context, AttributeSet attrs) {this(context, attrs, 0);}public BannerViewPager(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);this.mContext = context;initViews();}private void initViews() {//initialize the viewpagermViewPager = new ViewPager(mContext);ViewPager.LayoutParams lp = new ViewPager.LayoutParams();lp.width = ViewPager.LayoutParams.MATCH_PARENT;lp.height = ViewPager.LayoutParams.MATCH_PARENT;mViewPager.setLayoutParams(lp);jungle = new JungeValueChange();jungleValue = new JungeValue();jungle.addListener(jungleValue);//initialize the indicatormIndicator = new ViewPagerIndicator(mContext);FrameLayout.LayoutParams indicatorlp = new FrameLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);indicatorlp.gravity = Gravity.BOTTOM | Gravity.CENTER;indicatorlp.bottomMargin = 20;mIndicator.setLayoutParams(indicatorlp);mHandler.sendEmptyMessage(MESSAGE_ININTIAL_VIEW);}public void setAutoRolling(boolean isAutoRolling) {this.isAutoRolling = isAutoRolling;}public void setAutoRollingTime(int time) {this.mAutoRollingTime = time;}public void setAdapter(ViewPagerAdapter adapter) {mViewPager.setAdapter(adapter);mViewPager.addOnPageChangeListener(this);mAdapter = adapter;mAdapter.registerSubscriber(new DataSetSubscriber() {@Overridepublic void update(int count) {mIndicator.setItemCount(count);}});//add the viewpager and the indicator to the container.addView(mViewPager);addView(mIndicator);//start the auto-rolling task if neededif (isAutoRolling) {postDelayed(mAutoRollingTask, mAutoRollingTime);}}/*** If the current page is being dragged by the user,this method will be invoke.* And then it will call {@link ViewPagerIndicator#setPositionAndOffset}.** @param position Position index of the first page currently being displayed.* @param offset Value from [0, 1) indicating the offset from the page at position.*/private void setIndicator(int position, float offset) {mIndicator.setPositionAndOffset(position, offset);}/*** This runnable decides the viewpager should roll to next page or wait.*/private Runnable mAutoRollingTask = new Runnable() {@Overridepublic void run() {int now = (int) System.currentTimeMillis();int timediff = mAutoRollingTime;if (mReleasingTime != 0) {timediff = now - mReleasingTime;}if (mViewPagerScrollState == ViewPager.SCROLL_STATE_IDLE) {//if user's finger just left the screen,we should wait for a while.if (timediff >= mAutoRollingTime * 0.8) {mHandler.sendEmptyMessage(MESSAGE_AUTO_ROLLING);} else {mHandler.sendEmptyMessage(MESSAGE_AUTO_ROLLING_CANCEL);}} else if (mViewPagerScrollState == ViewPager.SCROLL_STATE_DRAGGING) {mHandler.sendEmptyMessage(MESSAGE_AUTO_ROLLING_CANCEL);} else if (mViewPagerScrollState == ViewPager.SCROLL_STATE_SETTLING) {mHandler.sendEmptyMessage(MESSAGE_AUTO_ROLLING_CANCEL);}}};
@Overridepublic void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {setIndicator(position, positionOffset);}//页面转到哪里@Overridepublic void onPageSelected(int position) {mCurrentPosition = position;if (mCurrentPosition == 0){mViewPager.setCurrentItem(mAdapter.getCount() - 2, true);}else if (mCurrentPosition == mAdapter.getCount() - 1){mViewPager.setCurrentItem(1, true);}}
//记录当页面滑动时状态的变化@Overridepublic void onPageScrollStateChanged(int state) {if (state == ViewPager.SCROLL_STATE_DRAGGING) {mViewPagerScrollState = ViewPager.SCROLL_STATE_DRAGGING;} else if (state == ViewPager.SCROLL_STATE_IDLE) {mReleasingTime = (int) System.currentTimeMillis();mViewPagerScrollState = ViewPager.SCROLL_STATE_IDLE;} else if (state == ViewPager.SCROLL_STATE_SETTLING) {mViewPagerScrollState = ViewPager.SCROLL_STATE_DRAGGING;}}/*** Save the state of this BannerViewPager.The current position will be saved.** @return Parcelable*/@Overrideprotected Parcelable onSaveInstanceState() {Parcelable parcelable = super.onSaveInstanceState();SavedState ss = new SavedState(parcelable);ss.currentPosition = mCurrentPosition;return ss;}/*** Restore the BannerViewPager from the previous state.** @param state*/@Overrideprotected void onRestoreInstanceState(Parcelable state) {SavedState ss = (SavedState) state;super.onRestoreInstanceState(ss.getSuperState());mViewPager.setCurrentItem(ss.currentPosition);}static class SavedState extends BaseSavedState {int currentPosition;public SavedState(Parcel source) {super(source);currentPosition = source.readInt();}public SavedState(Parcelable superState) {super(superState);}@Overridepublic void writeToParcel(Parcel out, int flags) {super.writeToParcel(out, flags);out.writeInt(currentPosition);}public static final Parcelable.Creator<SavedState> CREATOR = new Parcelable.Creator<SavedState>() {@Overridepublic SavedState createFromParcel(Parcel source) {return new SavedState(source);}@Overridepublic SavedState[] newArray(int size) {return new SavedState[size];}};}
}今晚有点事，晚点在写
先奉上代码
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