比如一些不规则按钮最好可以设置它的响应区域。如下图所示,用Polygon Collider2D组件圈出精灵响应事件的区域。
注意 IsRaycastLocationValid 的判断区域是RectTransform的区域。 如果 polygon Collider编辑出来的区域大于RectTransform , 必须调节RectTransform的区域。
例子:比如想把按钮的点击区域改成不规则的。
1.把按钮的image的RaycastTarget关闭勾选
2.在子节点创建新的gameObject挂上下面UIPolygon脚本。
3.编辑Polygon的区域即可。
C#
using UnityEngine;
using System.Collections;
using UnityEngine.UI;
#if UNITY_EDITOR
using UnityEditor;
#endif
[RequireComponent(typeof(PolygonCollider2D))]
public class UIPolygon : Image
{
private PolygonCollider2D _polygon = null;
private PolygonCollider2D polygon
{
get{
if(_polygon == null )
_polygon = GetComponent<PolygonCollider2D>();
return _polygon;
}
}
protected UIPolygon()
{
useLegacyMeshGeneration = true;
}
protected override void OnPopulateMesh(VertexHelper vh)
{
vh.Clear();
}
public override bool IsRaycastLocationValid(Vector2 screenPoint, Camera eventCamera)
{
return polygon.OverlapPoint( eventCamera.ScreenToWorldPoint(screenPoint));
}
#if UNITY_EDITOR
protected override void Reset()
{
base.Reset();
transform.localPosition = Vector3.zero;
float w = (rectTransform.sizeDelta.x *0.5f) + 0.1f;
float h = (rectTransform.sizeDelta.y*0.5f) + 0.1f;
polygon.points = new Vector2[]
{
new Vector2(-w,-h),
new Vector2(w,-h),
new Vector2(w,h),
new Vector2(-w,h)
};
}
#endif
}
#if UNITY_EDITOR
[CustomEditor(typeof(UIPolygon), true)]
public class UIPolygonInspector : Editor
{
public override void OnInspectorGUI()
{
}
}
#endif