unity3d手机滑动效果

using UnityEngine;
using System.Collections;

public class TestUI : MonoBehaviour {

public Vector2 scrollPosition = Vector2.zero;

public float scrollVelocity = 0f;

public float timeTouchPhaseEnded = 0f;

public float inertiaDuration = 0.5f;

public Vector2 lastDeltaPos;

// Use this for initialization
void Start () {}

void OnGUI(){
scrollPosition = GUI.BeginScrollView(new Rect(100, 40, 600, 400), scrollPosition, new Rect(0, 0, 500, 1600), false, true);

for (int i = 0; i < 32; i++){

   if(GUI.Button(new Rect(0, i*50, 400, 50), "Button"+i)){}
}
GUI.EndScrollView();

}

// Update is called once per frame

void Update () 
{

if (Input.touchCount > 0)
{
if (Input.GetTouch(0).phase == TouchPhase.Moved)
{
scrollPosition.y += Input.GetTouch(0).deltaPosition.y;

lastDeltaPos = Input.GetTouch(0).deltaPosition;

} 

else if (Input.GetTouch(0).phase == TouchPhase.Ended)

{
print ("End:"+lastDeltaPos.y+"|"+Input.GetTouch(0).deltaTime);

if (Mathf.Abs(lastDeltaPos.y)> 20.0f)



{



scrollVelocity = (int)(lastDeltaPos.y * 0.5/ Input.GetTouch(0).deltaTime);

print(scrollVelocity);

}
timeTouchPhaseEnded = Time.time;
}

}

else

{

if (scrollVelocity != 0.0f)
{

// slow down

float t = (Time.time - timeTouchPhaseEnded)/inertiaDuration;

float frameVelocity = Mathf.Lerp(scrollVelocity, 0, t);

scrollPosition.y += frameVelocity * Time.deltaTime;

if (t >= inertiaDuration)

scrollVelocity = 0;

}

}

}

}