Android Activity向右滑动返回

package com.kincai.store.ui;
 
import com.kincai.store.utils.LogTest;
 
import android.app.Activity;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.VelocityTracker;
 
/**
 * 
 * @company KCS互联网有限公司
 * 
 * @author kincai
 * 
 * @description baseActivity
 *
 * @project Kincai_Store
 *
 * @package com.kincai.store.ui
 *
 * @time 2015-7-13 上午10:18:29
 *
 */
public class BaseActivity extends Activity {
 
 
 // 手指上下滑动时的最小速度
 private static final int YSPEED_MIN = 1000;
 
 // 手指向右滑动时的最小距离
 private static final int XDISTANCE_MIN = 50;
 
 // 手指向上滑或下滑时的最小距离
 private static final int YDISTANCE_MIN = 66;
 
 private static final String TAG = "BaseActivity";
 
 // 记录手指按下时的横坐标。
 private float xDown;
 
 // 记录手指按下时的纵坐标。
 private float yDown;
 
 // 记录手指移动时的横坐标。
 private float xMove;
 
 // 记录手指移动时的纵坐标。
 private float yMove;
 
 // 用于计算手指滑动的速度。
 private VelocityTracker mVelocityTracker;
 
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 // TODO Auto-generated method stub
 super.onCreate(savedInstanceState);
 LogTest.LogMsg(TAG, "BaseActivity-onCreate");
 
 }
 
 @Override
 public boolean dispatchTouchEvent(MotionEvent event) {
 createVelocityTracker(event);
 switch (event.getAction()) {
 case MotionEvent.ACTION_DOWN:
 xDown = event.getRawX();
 yDown = event.getRawY();
 break;
 case MotionEvent.ACTION_MOVE:
 xMove = event.getRawX();
 yMove = event.getRawY();
 // 滑动的距离
 int distanceX = (int) (xMove - xDown);
 int distanceY = (int) (yMove - yDown);
 // 获取顺时速度
 int ySpeed = getScrollVelocity();
 // 关闭Activity需满足以下条件：
 // 1.x轴滑动的距离>XDISTANCE_MIN
 // 2.y轴滑动的距离在YDISTANCE_MIN范围内
 // 3.y轴上（即上下滑动的速度）<XSPEED_MIN，如果大于，则认为用户意图是在上下滑动而非左滑结束Activity
 if (distanceX > XDISTANCE_MIN
  && (distanceY < YDISTANCE_MIN && distanceY > -YDISTANCE_MIN)
  && ySpeed < YSPEED_MIN) {
 finish();
 }
 break;
 case MotionEvent.ACTION_UP:
 recycleVelocityTracker();
 break;
 default:
 break;
 }
 return super.dispatchTouchEvent(event);
 
 }
 
 /**
 * 创建VelocityTracker对象，并将触摸界面的滑动事件加入到VelocityTracker当中。
 * 
 * @param event
 * 
 */
 private void createVelocityTracker(MotionEvent event) {
 if (mVelocityTracker == null) {
 mVelocityTracker = VelocityTracker.obtain();
 }
 mVelocityTracker.addMovement(event);
 }
 
 /**
 * 回收VelocityTracker对象。
 */
 private void recycleVelocityTracker() {
 mVelocityTracker.recycle();
 mVelocityTracker = null;
 }
 
 /**
 * 
 * @return 滑动速度，以每秒钟移动了多少像素值为单位。
 */
 private int getScrollVelocity() {
 //1000速度
 mVelocityTracker.computeCurrentVelocity(1000);
 int velocity = (int) mVelocityTracker.getYVelocity();
 return Math.abs(velocity);
 }
 
 @Override
 protected void onStart() {
 // TODO Auto-generated method stub
 super.onStart();
 LogTest.LogMsg(TAG, "BaseActivity-onStart");
 }
 
 @Override
 protected void onResume() {
 // TODO Auto-generated method stub
 super.onResume();
 LogTest.LogMsg(TAG, "BaseActivity-onResume");
 }
 
 @Override
 protected void onPause() {
 // TODO Auto-generated method stub
 super.onPause();
 LogTest.LogMsg(TAG, "BaseActivity-onPause");
 }
 
 @Override
 protected void onDestroy() {
 // TODO Auto-generated method stub
 super.onDestroy();
 LogTest.LogMsg(TAG, "BaseActivity-onDestroy");
 }
 
}