求助，下面的代码有什么问题。停在第二章图片就没变化了，就3张图。

dim i as integer  'i设为全程变量

Private Sub Form_Click()
  
     P1(i).Visible = False
     i = i + 1
     P1(i).Visible = True
     
     If i = 3 Then
     i = 0
     End If
  
  
End Sub

Private Sub Form_Load()

Dim i As Integer
i = 0
P1(i).Visible = True

End Sub