UITextField在焦点上或使用objective-c开始编辑输入字段的背景颜色变化

Question

我是目标-c的新手，我遇到问题，我有一个输入文件，我试图在用户在UITextField上开始输入时更改输入字段背景颜色 对于输入文件我的代码是下面的

SELECT GEOGRAPHY , PROJECT ,
  CASE
    WHEN project_name = 'test1'
    THEN 'test1'
    WHEN project_name = 'test2'
    THEN 'test2'
    WHEN project_name    = 'test3'
    AND test_NAME = 'samp1'
    THEN 'gen1'
    WHEN project_name     = 'test3'
    AND  TEST_name <> 'samp1'
    THEN 'gen2'
    ELSE project_name
  END PROJECT_NAME from table 1
group by 
geography ,project_name,test_name.

提前致谢

Answer 1

选项1，使用委托

1. 将textfield Delegate设置为self

2. 设置viewController符合UITextfieldDelegate

   -(void)textFieldDidBeginEditing:(UITextField *)textField{
       textField.backgroundColor = [UIColor blueColor];
   }
   -(void)textFieldDidEndEditing:(UITextField *)textField{
       textField.backgroundColor = [UIColor whiteColor];
   }
   -(BOOL)textFieldShouldReturn:(UITextField *)textField{
     [textField resignFirstResponder];
     return true;
   }
   

选项2，使用目标操作

    [textfield addTarget:self action:@selector(textFieldBeginEditing:) forControlEvents:UIControlEventEditingDidBegin];

然后在函数中

-(void)textFieldBeginEditing:(UITextField *)textfield{
textfield.backgroundColor = [UIColor blueColor];
}