使用手势模拟左右滑动

<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.androiddemoset.MainActivity" >

<TextView
android:background="#000000"
android:layout_centerInParent="true"
android:layout_width="100dp"
android:layout_height="100dp"
android:textColor="#ffffff"
android:text="@string/hello_world"
android:id="@+id/tv"
android:gravity="center" />

</RelativeLayout>

package com.example.androiddemoset;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.GestureDetector;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.TextView;

public class MainActivity extends ActionBarActivity  implements OnTouchListener{

private GestureDetector detector;
private TextView tv;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
detector=new GestureDetector(this, new MyListener());
tv=(TextView)findViewById(R.id.tv);
tv.setClickable(true);
tv.setOnTouchListener(this);
}

private class MyListener extends SimpleOnGestureListener{
@Override// e1: 第一个MotionEvent_DOWN事件   e2： 最后的MotionEvent_UP事件
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
//触发条件：滑动距离大于50像素，水平移动速度大于50像素/秒
int min_fling_distance=50;
int min_velocityX=100;
//判断左滑事件
if(e1.getX()-e2.getX()>min_fling_distance&&Math.abs(velocityY)>min_velocityX){
Log.e("onFling", "左滑");
}
//判断右滑事件
if(e2.getX()-e1.getX()>min_fling_distance&&Math.abs(velocityX)>min_velocityX){
Log.e("onFling", "右滑");
}
return super.onFling(e1, e2, velocityX, velocityY);
}
}

@Override
public boolean onTouch(View arg0, MotionEvent arg1) {
return detector.onTouchEvent(arg1);
}

}