UItextField只获取焦点，不显示系统键盘

#pragma textDelegate

-(BOOL)textFieldShouldBeginEditing:(UITextField *)textField{

    //获取焦点后清空内容

//    textField.text = @"";

    textField.inputView=[[UIView alloc]initWithFrame:CGRectZero];

    self.CurrEnterItem = textField;

    self.userIsInTheMiddleofEnterANumber = true;

    return YES;

}