DataGrid last row can't checked by first CheckBox

[yanchao891012]

Describe the bug when the mouse click the datagrid last row‘s frist checkbox，row can't be checked.

To Reproduce Steps to reproduce the behavior:

1. Move mounse to datagrid last row
2. Click on first checkbox

Expected behavior click datagrid last row's first checkbox, the checkbox can be checked.

Screenshots

Environment (please complete the following information):

• .net: [e.g. 4.6.2]
• IDE [e.g. vs2017]
• Version [e.g. 1.0.0]

Additional context if datagrid use controltemplate , under controltemplate use button, datagrid last row's button can't be click also.