简单实现ScrollLayout

package com.example.administrator.scroller;import android.content.Context;import android.util.AttributeSet;import android.util.Log;import android.view.MotionEvent;import android.view.VelocityTracker;import android.view.View;import android.view.ViewConfiguration;import android.widget.AbsListView;import android.widget.FrameLayout;import android.widget.ListView;import android.widget.Scroller;/** * 支持ListView ,一般布局上下反弹 */public class ScrollContainerView extends FrameLayout{private final static float RATIO = 0.7f;private View mChildView;private int mLastY;private int mCurY;private int mYOffset;private Scroller mScroller;private ViewConfiguration mViewConfiguration;private int mTouchSlop;public ScrollContainerView(Context context, AttributeSet attrs) {super(context, attrs);mScroller = new Scroller(context);mViewConfiguration = ViewConfiguration.get(context);mTouchSlop = mViewConfiguration.getScaledMinimumFlingVelocity();//判断的触摸的最小速度Log.d("mTouchSlop=",mTouchSlop+"");}@Overrideprotected void onFinishInflate() {super.onFinishInflate();mChildView = getChildAt(0);}@Overridepublic boolean onInterceptTouchEvent(MotionEvent ev) {switch (ev.getAction()){case MotionEvent.ACTION_DOWN:Log.d("tag onIntercept","down");mCurY = (int)ev.getY();mLastY = mCurY;case MotionEvent.ACTION_MOVE:Log.d("tag onIntercept","move");mCurY = (int)ev.getY();int slop = Math.abs((mCurY - mLastY));int mark = mCurY - mLastY;Log.d("tag mCurY  mLastY",mCurY +"  "+ mLastY);Log.d("tag slop=",mark+"");mLastY = mCurY;Log.d("tag可以反弹？",enableScrollViewIsInTopOrBottom(mChildView,mark)+"");if (enableScrollViewIsInTopOrBottom(mChildView,mark) && slop > 10){return true;}break;case MotionEvent.ACTION_UP:Log.d("tag onIntercept","up");break;}return super.onInterceptTouchEvent(ev);}@Overridepublic boolean onTouchEvent(MotionEvent ev) {switch (ev.getAction()) {case MotionEvent.ACTION_DOWN:Log.d("tag onTouchEvent","down");mCurY = (int)ev.getY();mLastY = mCurY;case MotionEvent.ACTION_MOVE:Log.d("tag onTouchEvent","move");mCurY = (int)ev.getY();mYOffset = (int)((mCurY - mLastY)*RATIO);scrollBy(0,-mYOffset);//y负参数值下拉mLastY = mCurY;Log.d("getScrollY()",""+getScrollY());return true;case MotionEvent.ACTION_UP:Log.d("tag onTouchEvent","up");mCurY = 0;mLastY = 0;mYOffset = 0;if (!mScroller.isFinished()){mScroller.forceFinished(true);}mScroller.startScroll(0,getScrollY(),0,-getScrollY());invalidate();default:break;}return true;}@Overridepublic void computeScroll() {if (mScroller.computeScrollOffset()){scrollTo(mScroller.getCurrX(),mScroller.getCurrY());postInvalidate();}}/** * 判断会滚动的View是否位于顶部或者底部 * @param childview * @param offset 判断是上滑动还是下滑动 * @return */public  boolean enableScrollViewIsInTopOrBottom(View childview,int offset) {if (childview instanceof AbsListView) {return isListViewOnTopOrBottom(childview, offset);}return false;}private boolean isListViewOnTopOrBottom(View childview,int offset){AbsListView listView = (AbsListView)childview;if (listView.getLastVisiblePosition() == (listView.getCount() - 1) && offset < 0) {View bottomChildView = listView.getChildAt(listView.getLastVisiblePosition() - listView.getFirstVisiblePosition());return (listView.getHeight() >= bottomChildView.getBottom());}else if (listView.getFirstVisiblePosition() == 0 && offset > 0){return listView.getChildAt(listView.getFirstVisiblePosition()).getTop() == 0;}return false;}}

简单的运用了Scroller知识以及Touchu事件知识