本文转自xiaanming的博客（http://blog.csdn.net/xiaanming/article/details/17539199）
SlideCutListView：
package com.home.view;
import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.WindowManager;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.Scroller;
public class SlideCutListView extends ListView {
/**
* 当前滑动的ListView position
*/
private int slidePosition;
/**
* 手指按下X的坐标
*/
private int downX;
/**
* 手指按下Y的坐标
*/
private int downY;
/**
* 屏幕宽度
*/
private int screenWidth;
/**
* ListView的item
*/
private View itemView;
/**
* 滑动类
*/
private Scroller scroller;
private static final int SNAP_VELOCITY = 600;
/**
* 速度追踪对象
*/
private VelocityTracker velocityTracker;
/**
* 是否响应滑动，默认为不响应
*/
private boolean isSlide = false;
/**
* 认为是用户滑动的最小距离
*/
private int mTouchSlop;
/**
* 移除item后的回调接口
*/
private RemoveListener mRemoveListener;
/**
* 用来指示item滑出屏幕的方向,向左或者向右,用一个枚举值来标记
*/
private RemoveDirection removeDirection;
// 滑动删除方向的枚举值
public enum RemoveDirection {
RIGHT, LEFT;
}
public SlideCutListView(Context context) {
this(context, null);
}
public SlideCutListView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public SlideCutListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
screenWidth = ((WindowManager) context
.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay()
.getWidth();
scroller = new Scroller(context);
mTouchSlop = ViewConfiguration.get(getContext()).getScaledTouchSlop();
}
/**
* 设置滑动删除的回调接口
*
* @param removeListener
*/
public void setRemoveListener(RemoveListener removeListener) {
this.mRemoveListener = removeListener;
}
/**
* 分发事件，主要做的是判断点击的是那个item, 以及通过postDelayed来设置响应左右滑动事件
*/
@Override
public boolean dispatchTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN: {
addVelocityTracker(event);
// 假如scroller滚动还没有结束，我们直接返回
if (!scroller.isFinished()) {
return super.dispatchTouchEvent(event);
}
downX = (int) event.getX();
downY = (int) event.getY();
slidePosition = pointToPosition(downX, downY);
// 无效的position, 不做任何处理
if (slidePosition == AdapterView.INVALID_POSITION) {
return super.dispatchTouchEvent(event);
}
// 获取我们点击的item view
itemView = getChildAt(slidePosition - getFirstVisiblePosition());
break;
}
case MotionEvent.ACTION_MOVE: {
if (Math.abs(getScrollVelocity()) > SNAP_VELOCITY
|| (Math.abs(event.getX() - downX) > mTouchSlop && Math
.abs(event.getY() - downY) < mTouchSlop)) {
isSlide = true;
}
break;
}
case MotionEvent.ACTION_UP:
recycleVelocityTracker();
break;
}
return super.dispatchTouchEvent(event);
}
/**
* 往右滑动，getScrollX()返回的是左边缘的距离，就是以View左边缘为原点到开始滑动的距离，所以向右边滑动为负值
*/
private void scrollRight() {
removeDirection = RemoveDirection.RIGHT;
final int delta = (screenWidth + itemView.getScrollX());
// 调用startScroll方法来设置一些滚动的参数，我们在computeScroll()方法中调用scrollTo来滚动item
scroller.startScroll(itemView.getScrollX(), 0, -delta, 0,
Math.abs(delta));
postInvalidate(); // 刷新itemView
}
/**
* 向左滑动，根据上面我们知道向左滑动为正值
*/
private void scrollLeft() {
removeDirection = RemoveDirection.LEFT;
final int delta = (screenWidth - itemView.getScrollX());
// 调用startScroll方法来设置一些滚动的参数，我们在computeScroll()方法中调用scrollTo来滚动item
scroller.startScroll(itemView.getScrollX(), 0, delta, 0,
Math.abs(delta));
postInvalidate(); // 刷新itemView
}
/**
* 根据手指滚动itemView的距离来判断是滚动到开始位置还是向左或者向右滚动
*/
private void scrollByDistanceX() {
// 如果向左滚动的距离大于屏幕的二分之一，就让其删除
if (itemView.getScrollX() >= screenWidth / 2) {
scrollLeft();
} else if (itemView.getScrollX() <= -screenWidth / 2) {
scrollRight();
} else {
// 滚回到原始位置,为了偷下懒这里是直接调用scrollTo滚动
itemView.scrollTo(0, 0);
}
}
/**
* 处理我们拖动ListView item的逻辑
*/
@Override
public boolean onTouchEvent(MotionEvent ev) {
if (isSlide && slidePosition != AdapterView.INVALID_POSITION) {
requestDisallowInterceptTouchEvent(true);
addVelocityTracker(ev);
final int action = ev.getAction();
int x = (int) ev.getX();
switch (action) {
case MotionEvent.ACTION_DOWN:
break;
case MotionEvent.ACTION_MOVE:
MotionEvent cancelEvent = MotionEvent.obtain(ev);
cancelEvent
.setAction(MotionEvent.ACTION_CANCEL
| (ev.getActionIndex() << MotionEvent.ACTION_POINTER_INDEX_SHIFT));
onTouchEvent(cancelEvent);
int deltaX = downX - x;
downX = x;
// 手指拖动itemView滚动, deltaX大于0向左滚动，小于0向右滚
itemView.scrollBy(deltaX, 0);
return true; // 拖动的时候ListView不滚动
case MotionEvent.ACTION_UP:
int velocityX = getScrollVelocity();
if (velocityX > SNAP_VELOCITY) {
scrollRight();
} else if (velocityX < -SNAP_VELOCITY) {
scrollLeft();
} else {
scrollByDistanceX();
}
recycleVelocityTracker();
// 手指离开的时候就不响应左右滚动
isSlide = false;
break;
}
}
// 否则直接交给ListView来处理onTouchEvent事件
return super.onTouchEvent(ev);
}
@Override
public void computeScroll() {
// 调用startScroll的时候scroller.computeScrollOffset()返回true，
if (scroller.computeScrollOffset()) {
// 让ListView item根据当前的滚动偏移量进行滚动
itemView.scrollTo(scroller.getCurrX(), scroller.getCurrY());
postInvalidate();
// 滚动动画结束的时候调用回调接口
if (scroller.isFinished()) {
if (mRemoveListener == null) {
throw new NullPointerException(
"RemoveListener is null, we should called setRemoveListener()");
}
itemView.scrollTo(0, 0);
mRemoveListener.removeItem(removeDirection, slidePosition);
}
}
}
/**
* 添加用户的速度跟踪器
*
* @param event
*/
private void addVelocityTracker(MotionEvent event) {
if (velocityTracker == null) {
velocityTracker = VelocityTracker.obtain();
}
velocityTracker.addMovement(event);
}
/**
* 移除用户速度跟踪器
*/
private void recycleVelocityTracker() {
if (velocityTracker != null) {
velocityTracker.recycle();
velocityTracker = null;
}
}
/**
* 获取X方向的滑动速度,大于0向右滑动，反之向左
*
* @return
*/
private int getScrollVelocity() {
velocityTracker.computeCurrentVelocity(1000);
int velocity = (int) velocityTracker.getXVelocity();
return velocity;
}
/**
*
* 当ListView item滑出屏幕，回调这个接口 我们需要在回调方法removeItem()中移除该Item,然后刷新ListView
*
* @author xiaanming
*
*/
public interface RemoveListener {
public void removeItem(RemoveDirection direction, int position);
}
}主页面调用：
实现RemoveListener
mListView=(SlideCutListView) findViewById(R.id.main_lv);
mListView.setRemoveListener(this); @Override
public void removeItem(RemoveDirection direction, int position) {
mAdapter.remove(mAdapter.getItem(position));
}