ViewPager的弹性缩回效果

         android 实现划屏效果控件有：ViewFlipper,用过的同学们都知道，这个控件有点死板,只能等待你手势执行完毕后才执行滑动效果，用起来很不爽，不过ViewPager可以很容易实现这个效果.但是有个缺陷，也就是在首页时候向左拽，在最后一页向右拽，这两者是没有效果的，而iphone的效果是你拖拽出现一片空的page会自动缩回首页或尾页，这个看起来很爽，不过android强大之处你可以自己实现，我是菜鸟，说的都是个人观点，获取有很多很多的bug吧，若有不足之处请您多多指出，我将感激不尽.
       首先要实现ViewPager效果，必须要导入一个jar包“android-support-v4.jar”这个jar包可以在android sdk中找到路径为”E:\android-sdk-windows\extras\android\support\v4“
          关于细节上的问题，自己可以网上搜搜.在这里我要讲两点”怎么实现禁止滑向下一页“
          其实实现方法很简单，一说你也就知道了.”多创建两个屏，用于放在第一屏和最后一屏“嘿嘿，知道了吧，我其实也没做什么，就是稍微修改了一下，具体代码如下：
        主要是这个回调 OnPageChangeListener接口,当页数改变回调用，也就是当你左右滑动的时候会执行,还有一个重要的方法：pager.setCurrentItem(arg0 - 1);你要显示哪一页的时候也会调用调用.

源码已经优化：

package com.jj.viewpager;import java.util.ArrayList;import android.app.ActivityGroup;import android.content.Intent;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.ViewGroup.LayoutParams;import android.widget.ImageView;import android.widget.LinearLayout;public class MainActivity extends ActivityGroup {private ViewPager pager;private ArrayList<View> pageViews=new ArrayList<View>();private LinearLayout layout;private int curPosition=1;//当前显示页,从1开始private ArrayList<ImageView> imageViews;private int points;//多少个点@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);initViews();}void initViews() {View view00 = getLocalActivityManager().startActivity("activity00",new Intent(this, NullActivity.class)).getDecorView();View view01 = getLocalActivityManager().startActivity("activity01",new Intent(this, MainActivity1.class)).getDecorView();View view02 = getLocalActivityManager().startActivity("activity02",new Intent(this, MainActivity2.class)).getDecorView();View view03 = getLocalActivityManager().startActivity("activity03",new Intent(this, MainActivity3.class)).getDecorView();View view04 = getLocalActivityManager().startActivity("activity00",new Intent(this, NullActivity.class)).getDecorView();pageViews.add(view00);pageViews.add(view01);pageViews.add(view02);pageViews.add(view03);pageViews.add(view04);pager = (ViewPager) findViewById(R.id.vp_contains);pager.setAdapter(new PagerViewAdapter());pager.setCurrentItem(curPosition);pager.setOnPageChangeListener(new OnPageChangeListener() {@Overridepublic void onPageSelected(int position) {if (position == 0) {pager.setCurrentItem(position + 1);} else if(position == pageViews.size() - 1){pager.setCurrentItem(position - 1);}updateViews(pager.getCurrentItem());}@Overridepublic void onPageScrolled(int arg0, float arg1, int arg2) {}@Overridepublic void onPageScrollStateChanged(int arg0) {}});imageViews = new ArrayList<ImageView>();layout = (LinearLayout) findViewById(R.id.layout);points=pageViews.size()-2;for (int i = 0; i < points; i++) {ImageView imageView = new ImageView(this);imageView.setLayoutParams(new LayoutParams(5, 5));LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(new ViewGroup.LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT));params.leftMargin = 20;params.rightMargin = 20;layout.addView(imageView, params);imageViews.add(imageView);imageView.setBackgroundResource(i == pager.getCurrentItem()-1?R.drawable.d2:R.drawable.d1);}}public void updateViews(int index) {for (int i = 0; i < points; i++) {imageViews.get(i).setBackgroundResource(i==index-1?R.drawable.d2:R.drawable.d1);}}class PagerViewAdapter extends PagerAdapter {@Overridepublic int getCount() {return pageViews.size();}@Overridepublic boolean isViewFromObject(View arg0, Object arg1) {return arg0 == arg1;}@Overridepublic int getItemPosition(Object object) {// TODO Auto-generated method stubreturn super.getItemPosition(object);}@Overridepublic void destroyItem(View arg0, int arg1, Object arg2) {// TODO Auto-generated method stub((ViewPager) arg0).removeView(pageViews.get(arg1));}@Overridepublic Object instantiateItem(View arg0, int arg1) {((ViewPager) arg0).addView(pageViews.get(arg1));return pageViews.get(arg1);}}}

完整的看附件。

简单方法实现ViewPage 循环滚动

ViewPager之——水平滑动弹性效果
http://stackoverflow.com/questions/13759862/android-viewpager-how-to-achieve-the-bound-effect

上面的方式不靠谱，还是用这个吧，好东西总是在最后。

public class BounceBackViewPager extends ViewPager {/** * maximum z distance to translate child view */final static int DEFAULT_OVERSCROLL_TRANSLATION = 150;/** * duration of overscroll animation in ms */final private static int DEFAULT_OVERSCROLL_ANIMATION_DURATION = 400;@SuppressWarnings("unused")private final static String DEBUG_TAG = ViewPager.class.getSimpleName();private final static int INVALID_POINTER_ID = -1;/** *  * @author renard, extended by Piotr Zawadzki *  */private class OverscrollEffect {    private float mOverscroll;    private Animator mAnimator;    /**     * @param deltaDistance [0..1] 0->no overscroll, 1>full overscroll     */    public void setPull(final float deltaDistance) {        mOverscroll = deltaDistance;        invalidateVisibleChilds(mLastPosition);    }    /**     * called when finger is released. starts to animate back to default position     */    private void onRelease() {        if (mAnimator != null && mAnimator.isRunning()) {            mAnimator.addListener(new AnimatorListener() {                @Override                public void onAnimationStart(Animator animation) {                }                @Override                public void onAnimationRepeat(Animator animation) {                }                @Override                public void onAnimationEnd(Animator animation) {                    startAnimation(0);                }                @Override                public void onAnimationCancel(Animator animation) {                }            });            mAnimator.cancel();        } else {            startAnimation(0);        }    }    private void startAnimation(final float target) {        mAnimator = ObjectAnimator.ofFloat(this, "pull", mOverscroll, target);        mAnimator.setInterpolator(new DecelerateInterpolator());        final float scale = Math.abs(target - mOverscroll);        mAnimator.setDuration((long) (mOverscrollAnimationDuration * scale));        mAnimator.start();    }    private boolean isOverscrolling() {        if (mScrollPosition == 0 && mOverscroll < 0) {            return true;        }        final boolean isLast = (getAdapter().getCount() - 1) == mScrollPosition;        if (isLast && mOverscroll > 0) {            return true;        }        return false;    }}final private OverscrollEffect mOverscrollEffect = new OverscrollEffect();final private Camera mCamera = new Camera();private OnPageChangeListener mScrollListener;private float mLastMotionX;private int mActivePointerId;private int mScrollPosition;private float mScrollPositionOffset;final private int mTouchSlop;private float mOverscrollTranslation;private int mOverscrollAnimationDuration;public BounceBackViewPager(Context context, AttributeSet attrs) {    super(context, attrs);    setStaticTransformationsEnabled(true);    final ViewConfiguration configuration = ViewConfiguration.get(context);    mTouchSlop = ViewConfigurationCompat.getScaledPagingTouchSlop(configuration);    super.setOnPageChangeListener(new MyOnPageChangeListener());    init(attrs);}private void init(AttributeSet attrs) {    TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.BounceBackViewPager);    mOverscrollTranslation = a.getDimension(R.styleable.BounceBackViewPager_overscroll_translation, DEFAULT_OVERSCROLL_TRANSLATION);    mOverscrollAnimationDuration = a.getInt(R.styleable.BounceBackViewPager_overscroll_animation_duration, DEFAULT_OVERSCROLL_ANIMATION_DURATION);    a.recycle();}public int getOverscrollAnimationDuration() {    return mOverscrollAnimationDuration;}public void setOverscrollAnimationDuration(int mOverscrollAnimationDuration) {    this.mOverscrollAnimationDuration = mOverscrollAnimationDuration;}public float getOverscrollTranslation() {    return mOverscrollTranslation;}public void setOverscrollTranslation(int mOverscrollTranslation) {    this.mOverscrollTranslation = mOverscrollTranslation;}@Overridepublic void setOnPageChangeListener(OnPageChangeListener listener) {    mScrollListener = listener;};private void invalidateVisibleChilds(final int position) {     for (int i = 0; i < getChildCount(); i++) {     getChildAt(i).invalidate();     }    //this.invalidate();    // final View child = getChildAt(position);    // final View previous = getChildAt(position - 1);    // final View next = getChildAt(position + 1);    // if (child != null) {    // child.invalidate();    // }    // if (previous != null) {    // previous.invalidate();    // }    // if (next != null) {    // next.invalidate();    // }}private int mLastPosition = 0;private class MyOnPageChangeListener implements OnPageChangeListener {    @Override    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {        if (mScrollListener != null) {            mScrollListener.onPageScrolled(position, positionOffset, positionOffsetPixels);        }        mScrollPosition = position;        mScrollPositionOffset = positionOffset;        mLastPosition = position;        invalidateVisibleChilds(position);    }    @Override    public void onPageSelected(int position) {        if (mScrollListener != null) {            mScrollListener.onPageSelected(position);        }    }    @Override    public void onPageScrollStateChanged(final int state) {        if (mScrollListener != null) {            mScrollListener.onPageScrollStateChanged(state);        }        if (state == SCROLL_STATE_IDLE) {            mScrollPositionOffset = 0;        }    }}@Overridepublic boolean onInterceptTouchEvent(MotionEvent ev) {    try {        final int action = ev.getAction() & MotionEventCompat.ACTION_MASK;        switch (action) {        case MotionEvent.ACTION_DOWN: {            mLastMotionX = ev.getX();            mActivePointerId = MotionEventCompat.getPointerId(ev, 0);            break;        }        case MotionEventCompat.ACTION_POINTER_DOWN: {            final int index = MotionEventCompat.getActionIndex(ev);            final float x = MotionEventCompat.getX(ev, index);            mLastMotionX = x;            mActivePointerId = MotionEventCompat.getPointerId(ev, index);            break;        }        }        return super.onInterceptTouchEvent(ev);    } catch (IllegalArgumentException e) {        e.printStackTrace();        return false;    } catch (ArrayIndexOutOfBoundsException e) {        e.printStackTrace();        return false;    }}@Overridepublic boolean dispatchTouchEvent(MotionEvent ev) {    try {        return super.dispatchTouchEvent(ev);    } catch (IllegalArgumentException e) {        e.printStackTrace();        return false;    } catch (ArrayIndexOutOfBoundsException e) {        e.printStackTrace();        return false;    }}@Overridepublic boolean onTouchEvent(MotionEvent ev) {    boolean callSuper = false;    final int action = ev.getAction();    switch (action) {    case MotionEvent.ACTION_DOWN: {        callSuper = true;        mLastMotionX = ev.getX();        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);        break;    }    case MotionEventCompat.ACTION_POINTER_DOWN: {        callSuper = true;        final int index = MotionEventCompat.getActionIndex(ev);        final float x = MotionEventCompat.getX(ev, index);        mLastMotionX = x;        mActivePointerId = MotionEventCompat.getPointerId(ev, index);        break;    }    case MotionEvent.ACTION_MOVE: {        if (mActivePointerId != INVALID_POINTER_ID) {            // Scroll to follow the motion event            final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);            final float x = MotionEventCompat.getX(ev, activePointerIndex);            final float deltaX = mLastMotionX - x;            final float oldScrollX = getScrollX();            final int width = getWidth();            final int widthWithMargin = width + getPageMargin();            final int lastItemIndex = getAdapter().getCount() - 1;            final int currentItemIndex = getCurrentItem();            final float leftBound = Math.max(0, (currentItemIndex - 1) * widthWithMargin);            final float rightBound = Math.min(currentItemIndex + 1, lastItemIndex) * widthWithMargin;            final float scrollX = oldScrollX + deltaX;            if (mScrollPositionOffset == 0) {                if (scrollX < leftBound) {                    if (leftBound == 0) {                        final float over = deltaX + mTouchSlop;                        mOverscrollEffect.setPull(over / width);                    }                } else if (scrollX > rightBound) {                    if (rightBound == lastItemIndex * widthWithMargin) {                        final float over = scrollX - rightBound - mTouchSlop;                        mOverscrollEffect.setPull(over / width);                    }                }            } else {                mLastMotionX = x;            }        } else {            mOverscrollEffect.onRelease();        }        break;    }    case MotionEvent.ACTION_UP:    case MotionEvent.ACTION_CANCEL: {        callSuper = true;        mActivePointerId = INVALID_POINTER_ID;        mOverscrollEffect.onRelease();        break;    }    case MotionEvent.ACTION_POINTER_UP: {        final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >> MotionEvent.ACTION_POINTER_INDEX_SHIFT;        final int pointerId = MotionEventCompat.getPointerId(ev, pointerIndex);        if (pointerId == mActivePointerId) {            // This was our active pointer going up. Choose a new            // active pointer and adjust accordingly.            final int newPointerIndex = pointerIndex == 0 ? 1 : 0;            mLastMotionX = ev.getX(newPointerIndex);            mActivePointerId = MotionEventCompat.getPointerId(ev, newPointerIndex);            callSuper = true;        }        break;    }    }    if (mOverscrollEffect.isOverscrolling() && !callSuper) {        return true;    } else {        return super.onTouchEvent(ev);    }}@Overrideprotected boolean getChildStaticTransformation(View child, Transformation t) {    if (child.getWidth() == 0) {        return false;    }    final int position = child.getLeft() / child.getWidth();    final boolean isFirstOrLast = position == 0 || (position == getAdapter().getCount() - 1);    if (mOverscrollEffect.isOverscrolling() && isFirstOrLast) {        final float dx = getWidth() / 2;        final int dy = getHeight() / 2;        t.getMatrix().reset();        final float translateX =(float) mOverscrollTranslation * (mOverscrollEffect.mOverscroll > 0 ? Math.min(mOverscrollEffect.mOverscroll, 1) : Math.max(mOverscrollEffect.mOverscroll, -1));        mCamera.save();        mCamera.translate(-translateX, 0, 0);        mCamera.getMatrix(t.getMatrix());        mCamera.restore();        t.getMatrix().preTranslate(-dx, -dy);        t.getMatrix().postTranslate(dx, dy);        if (getChildCount() == 1) {            this.invalidate();        } else {            child.invalidate();        }        return true;    }    return false;}}

<?xml version="1.0" encoding="utf-8"?><resources><declare-styleable name="BounceBackViewPager">    <!--    determines the maximum amount of translation along the z-axis during the overscroll.     Default is 150.    -->    <attr name="overscroll_translation" format="dimension" />    <!-- Duration of animation when user releases the over scroll. Default is 400 ms. -->    <attr name="overscroll_animation_duration" format="integer" /></declare-styleable>

子ViewPager滑到边缘后直接滑动父ViewPager
http://blog.csdn.net/lcq5211314123/article/details/41248569

ViewPager之——3D效果应用
http://blog.csdn.net/lcq5211314123/article/details/41120315


Android 教你打造炫酷的ViewPagerIndicator 不仅仅是高仿MIUI
http://blog.csdn.net/lmj623565791/article/details/42160391

打造史上最容易使用的Tab指示符——Indicator
http://blog.csdn.net/qibin0506/article/details/42046559

一个ViewPager的库，支持水平翻页，上下翻页，无限翻页
http://www.jcodecraeer.com/a/opensource/2015/0207/2430.html


MultiViewPager 是根据support-v4 中ViewPager 控件改造而来，它可以让ViewPager一次显示更宽或者更窄的内容，它很好的处理了page之间的位置关系，能保证每次被选中的page显示在中间。
http://www.jcodecraeer.com/a/opensource/2015/0207/2432.html