UITextField 的 inputView 弹出自定义View 然后第一次还是弹出键盘，第二次才是自定义的View

如题 有人遇到此类问题吗？
self.datePicker = [[UIDatePicker alloc]init];
self.datePicker.backgroundColor = [UIColor whiteColor];
self.datePicker.datePickerMode = UIDatePickerModeDate;

[cell.contentTextField becomeFirstResponder];
cell.contentTextField.inputView = self.datePicker;

大概代码只有这么多

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[cell.contentTextField becomeFirstResponder];
cell.contentTextField.inputView = self.sexPickerView;

改成

cell.contentTextField.inputView = self.sexPickerView;
[cell.contentTextField becomeFirstResponder];