//
//  RootViewController.m
//  UITextField
//
//  Created by YouXianMing on 14-9-15.
//  Copyright (c) 2014年 YouXianMing. All rights reserved.
//

#import "RootViewController.h"@interface RootViewController ()<UITextFieldDelegate>@property (nonatomic, strong) UITextField *textField;@end@implementation RootViewController- (void)viewDidLoad
{[super viewDidLoad];_textField                      = [[UITextField alloc] initWithFrame:CGRectMake(10,  80, 300, 40)];_textField.layer.borderWidth    = 1.f;_textField.layer.borderColor    = [UIColor redColor].CGColor;_textField.backgroundColor      = [UIColor whiteColor];_textField.textAlignment        = kCTTextAlignmentLeft;    // 左对齐_textField.delegate             = self ;_textField.keyboardType         = UIKeyboardTypeNumberPad; // 数字键盘_textField.placeholder          = @"请输入4位验证码";_textField.clearsOnBeginEditing = YES;// 空出左侧边缘空隙（通过添加一个view来实现）UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 10,CGRectGetHeight(_textField.bounds))];_textField.leftView     = view;_textField.leftViewMode = UITextFieldViewModeAlways;[self.view addSubview:_textField];// 添加手势
    [self addGesture];
}- (void)addGesture
{// 手势UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapGesture:)];[self.view addGestureRecognizer:tap];
}// 限制输入长度
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{if (range.location >= 4){return NO;}else{return YES;}
}- (void)tapGesture:(UITapGestureRecognizer *)tap
{// 取消第一响应状态
    [_textField resignFirstResponder];
}@end