豪哥学ios开发之登录界面

首先在ViewController.h文件中：

#import <UIKit/UIKit.h>

#import "SRWebSocket.h"

//继承SRWebSocket.h，作为登录服务器

@interface ViewController : UIViewController<UITextFieldDelegate,SRWebSocketDelegate>

//- (IBAction)SaveLogin:(id)sender;

//与SB联系账号输入，密码输入与登录按钮，并且设置两个label写上提示账号和密码输入

@property (weak, nonatomic) IBOutlet UITextField *userName;

@property (weak, nonatomic) IBOutlet UITextField *password;

- (IBAction)loginbuttonClick:(id)sender;

@property (weak, nonatomic) IBOutlet UIButton *loginButton;

//@property (weak, nonatomic) IBOutlet UIButton *SaveLogin;

@property (weak, nonatomic) IBOutlet UILabel *lbuser;

@property (weak, nonatomic) IBOutlet UILabel *lbpassword;

@end

然后来到.m文件中：

#import "ViewController.h"

#import "ASIHTTPRequest.h"

#import "MD5.h"

#import "SVProgressHUD.h"

#import "Reachability.h"

#import "UIColor+Extensions.h"

#import "comm.h"

//引用ASIHTTPRequest.h发送请求，MD5将账号密码转译，Reachability.h检查网络链接状态，SVProgressHUD.h后期开发就不用了，UIColor+Extensions.h颜色扩展，comm.h定义聊天服务器，登录服务器地址方便调用

@interface ViewController ()

{

    UIImageView *slashimage;

}

@end

@implementation ViewController

- (void)viewDidLoad

{

    [super viewDidLoad];

    CGSize viewSize = [[UIScreen mainScreen] bounds].size;

    //设置登录界面背景图片；

    UIImageView *image = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"bg.png"]];

    //采用自身视图尺寸作为背景大小；

    [image setFrame:self.view.frame];

    [self.view addSubview:image];

    //把背景图放在最底层，不会被释放；

    [self.view sendSubviewToBack:image];

    //调用键盘的三种状态，对应三种状态需要采用的方法；

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyBoardWillShow:) name:UIKeyboardWillShowNotification object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyBoardWillHide:) name:UIKeyboardWillHideNotification object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(textFieldChanged:) name:UITextFieldTextDidChangeNotification object:nil];

  //设置代理；

    self.userName.delegate = self;

    self.password.delegate = self;

    //隐藏导航栏；

    [self.navigationController.navigationBar setHidden:YES];

    //实现轻量本地化，把账号密码对应相关key存在NSUserDefaults；

    NSUserDefaults *pref = [NSUserDefaults standardUserDefaults];

    NSString* strUid = [pref stringForKey:@"uid"];

    NSString* strPwd = [pref stringForKey:@"pwd"];

    //取出输入框中的对象，赋给变量；

    self.userName.text = strUid;

    self.password.text = strPwd;

    //利用美术组提供的颜色给字体提供新的颜色；

    self.userName.textColor = [UIColor colorWithHexString:@"767676"];

    self.password.textColor = [UIColor colorWithHexString:@"767676"];

    //判断输入框中的对象不为空时，登录按钮才可用

    if ([self.userName.text isEqualToString:@""] || [self.password.text isEqualToString:@""])

    {

        [self.loginButton setEnabled:FALSE];

        self.loginButton.titleLabel.textColor = [UIColor grayColor];

    }

    else

    {

        [self.loginButton setEnabled:TRUE];

        self.loginButton.titleLabel.textColor = [UIColor whiteColor];

    }

    self.lbuser.backgroundColor = [UIColor colorWithHexString:@"b5b5b5"];

    self.lbpassword.backgroundColor = [UIColor colorWithHexString:@"b5b5b5"];

    self.loginButton.layer.borderWidth = 1.0f;//定义登录按钮边框

    self.loginButton.layer.borderColor = [[UIColor whiteColor] CGColor];

    self.loginButton.layer.cornerRadius = 4.0;

    self.loginButton.titleLabel.textColor = [UIColor whiteColor];

    self.loginButton.backgroundColor = [UIColor colorWithRed:255.0/255.0 green:255.0/255.0 blue:255.0/255.0 alpha:0.15];

    //[self performSegueWithIdentifier:@"gotoHome" sender:self.loginButton];

    //登录背景设置；

    slashimage = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"Default-568h@2x.png"]];

    [slashimage setFrame:self.view.frame];

    [self.view addSubview:slashimage];

    //登录动画方法；

    [self performSelector:@selector(hideSlashImage) withObject:nil afterDelay:1.0];

}

- (void)hideSlashImage

{

    [UIView animateWithDuration:0.8 animations:^{

        slashimage.alpha = 0.0;

    } completion:^(BOOL finished) {

        [slashimage removeFromSuperview];

    }];

}

- (void) viewWillAppear:(BOOL)animated

{

    CGSize viewSize = [[UIScreen mainScreen] bounds].size;

    //在视图即将出现时，需要

    NSUserDefaults *pref = [NSUserDefaults standardUserDefaults];

    NSString* strUid = [pref stringForKey:@"uid"];

    NSString* strPwd = [pref stringForKey:@"pwd"];

    self.userName.text = strUid;

    self.password.text = strPwd;

    [[NSNotificationCenter defaultCenter]

     addObserver:self

     selector:@selector(applicationDidBecomeActiveNotification:)

     name:UIApplicationDidBecomeActiveNotification

     object:[UIApplication sharedApplication]];

}

- (void) viewWillDisappear:(BOOL)animated

{

}

- (void)applicationDidBecomeActiveNotification:(NSNotification *)notification {

    // Do something here

    //通过取消第一响应者来隐藏键盘位置

    [self.userName resignFirstResponder];

    [self.password resignFirstResponder];

}

- (void)viewDidAppear:(BOOL)animated

{

}

- (void)didReceiveMemoryWarning

{

    [super didReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}

- (IBAction)loginbuttonClick:(id)sender

{

   //向管理平台登录，获取token，并且用将账号密码转为md5格式；

    NSString *strUrl = [NSString stringWithFormat:@"%@/login?tel=%@&pwd=%@",WEB_SERVER_HOST,

                        self.userName.text,[self.password.text MD5EncodedString]];

    NSLog(@"%@",strUrl);

    //发送异步请求

    NSString *strMd5 = [NSString stringWithMD5EncodedString:@"19"];

    NSURL *url = [NSURL URLWithString:strUrl];

    __block ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url];

    [request setCompletionBlock:^{

        // Use when fetching text data

        NSString *responseString = [request responseString];

        NSLog(@"login result:%@",responseString);

        NSError *error = nil;

        NSData *jsonData = [responseString dataUsingEncoding:NSUTF8StringEncoding];

        NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:jsonData options:kNilOptions error:&error];

        NSString* msgCode = [dict objectForKey:@"code"];

        if ([msgCode isEqualToString:@"200"]) {

            NSLog(@"login success!");

            NSString* token = [dict objectForKey:@"token"];//登录成功就获取token，并保存在NSUserDefaults

            NSUserDefaults *pref = [NSUserDefaults standardUserDefaults];

            [pref setValue:token forKey:@"logintoken"];

            [pref setValue:self.userName.text forKey:@"uid"];

            [pref setValue:self.password.text forKey:@"pwd"];

            [pref setBool:TRUE forKey:@"login"];//将登录状态也保存，

            //NSString *msgResult = [[dict objectForKey:@"result"] description];

            [pref setValue:responseString forKey:@"loginresult"];//将返回的信息保存，以后要解析

            //[SVProgressHUD dismiss];

            //取消第一响应者，隐藏键盘

            [self.userName resignFirstResponder];

            [self.password resignFirstResponder];

            //切换试图，进入主界面

            [self performSegueWithIdentifier:@"gotoHome" sender:self.loginButton];

        }

        else {

            [SVProgressHUD showErrorWithStatus:@"用户名或密码有误，请重新输入。"];

            NSUserDefaults *pref = [NSUserDefaults standardUserDefaults];

            [pref setBool:FALSE forKey:@"login"];

            return;

        }

        NSLog(@"msgCode is %@",msgCode);

    }];

    [request setFailedBlock:^{

        NSError *error = [request error];

        NSLog(@"login result:%@",error.description);

        //因网络原因登录失败提示弹窗

        UIAlertView *alert = [[UIAlertView alloc]initWithTitle:nil message:@"请检查您的网络后重试!" delegate:nil cancelButtonTitle:@"Ok" otherButtonTitles:nil];

        [alert show];

    }];

    [request startAsynchronous];

}

#pragma mark - 键盘处理

#pragma mark 键盘即将显示

- (void)keyBoardWillShow:(NSNotification *)note{

    CGRect rect = [note.userInfo[UIKeyboardFrameEndUserInfoKey] CGRectValue];//根据键盘的这个key来取键盘消失时候的值;

    CGFloat ty = self.view.frame.size.height - rect.size.height;//屏幕高度减去键盘高度的值;

    CGFloat shift = ty - self.loginButton.frame.origin.y-self.loginButton.frame.size.height;//设置底边高度；

    //将视图坐标向上推；

    [UIView animateWithDuration:[note.userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue] animations:^{

        self.view.transform = CGAffineTransformMakeTranslation(0, shift);

    }];

}

#pragma mark 键盘即将退出

- (void)keyBoardWillHide:(NSNotification *)note{

    //视图返回原位，CGAffineTransformIdentity是没有使用transform之前的值；

    [UIView animateWithDuration:[note.userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue] animations:^{

        self.view.transform = CGAffineTransformIdentity;

    }];

}

- (void)textFieldChanged:(NSNotification *)note{

    if ([self.userName.text isEqualToString:@""] || [self.password.text isEqualToString:@""])

    {

        [self.loginButton setEnabled:FALSE];

        self.loginButton.titleLabel.textColor = [UIColor grayColor];

    }

    else

    {

        [self.loginButton setEnabled:TRUE];

        self.loginButton.titleLabel.textColor = [UIColor whiteColor];

    }

}

- (BOOL)shouldPerformSegueWithIdentifier:(NSString *)identifier sender:(id)sender

{

    //默认不跳转，等待登陆结果

    NSUserDefaults *pref = [NSUserDefaults standardUserDefaults];

    BOOL blogin = [pref boolForKey:@"login"];

    if (blogin) {

        return TRUE;

    }

    return FALSE;

}

// In a storyboard-based application, you will often want to do a little preparation before navigation

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender

{

 }

@end

原文：http://www.cnblogs.com/tuhaoYY/p/3860104.html