在实际开发中，常常需求我们在输入框textField中添加各种辅助视图，例如图：
示意图.png
实现代码如下：
-(void)configUI{
self.title = @"修改手机号";
self.view.backgroundColor = [UIColor groupTableViewBackgroundColor];
//手机Icon
UIButton *telImv = [[UIButton alloc]initWithFrame:CGRectMake(10, 0, 30, 20)];
[telImv setImage:[UIImage imageNamed:@"icon_phone"] forState:UIControlStateNormal];
telImv.userInteractionEnabled = NO;
//设置textField 的 rightView属性和 rightViewMode的属性
self.telTF.leftView = telImv;
self.telTF.leftViewMode = UITextFieldViewModeAlways;
//验证码Icon
UIButton *verifyImv = [[UIButton alloc]initWithFrame:CGRectMake(10, 0, 30, 20)];
[verifyImv setImage:[UIImage imageNamed:@"icon_code"] forState:UIControlStateNormal];
verifyImv.userInteractionEnabled = NO;
self.verifyTF.leftView = verifyImv;
self.verifyTF.leftViewMode = UITextFieldViewModeAlways;
//验证码Button
UIButton *verifyBtn = [[UIButton alloc]initWithFrame:CGRectMake(0, 0, 100, 40)];
[verifyBtn.titleLabel setFont:[UIFont systemFontOfSize:13]];
[verifyBtn setTitle:@"获取验证码" forState:UIControlStateNormal];
[verifyBtn setTitleColor:[UIColor orangeColor] forState:UIControlStateNormal];
self.verifyTF.rightView = verifyBtn;
self.verifyTF.rightViewMode = UITextFieldViewModeAlways;
[verifyBtn addTarget:self action:@selector(getVerifyCode:) forControlEvents:UIControlEventTouchUpInside];
}
判断文字输入状态，正在输入有灰条覆盖
if (!self.textField.markedTextRange) {
NSLog(@"输入完成才会进入");
}
验证码倒计时方法，请参考链接：http://www.jianshu.com/p/e806cee61a7b
