Modify of shader and scrollview donot clip

[lzt120]

I modify the shader of "Unlit/Transparent Colored" as below list but this lead to that scroll-view does not clip any more when I am dragging. How can I fixed this ?
 

1. //_GreyColor("GreyColor", Color) = (0.299, 0.587, 0.114,1)
2. if (i.color.r < 0.001)  
3. {  
4.     col = tex2D(_MainTex, i.texcoord);  
5.     float grey = dot(col.rgb, float3(_GreyColor.r,_GreyColor.g,_GreyColor.b));  
6.     col.rgb = float3(grey, grey, grey);  
7.                                
8. }  
9. else
10. {
11.     col = tex2D(_MainTex, i.texcoord) * i.color;  
12. }  

[ArenMook]

Unlit/Transparent Colored shader doesn't do clipping. Clipping happens in the numbered versions of this shader such as Unlit - Transparent Colored 1.