注意：如果勾选了Use Size Classes，上图中用于登录的Segue的push就得换成show。
#import "LXViewController.h"
@interface LXViewController ()
@property (weak, nonatomic) IBOutlet UITextField *account;
@property (weak, nonatomic) IBOutlet UITextField *password;
@property (weak, nonatomic) IBOutlet UIButton *LoginBtn;
- (IBAction)LoginClick;
@end
@implementation LXViewController
- (void)viewDidLoad {
[super viewDidLoad];
[self.account addTarget:self action:@selector(textChange) forControlEvents:UIControlEventEditingChanged];
[self.password addTarget:self action:@selector(textChange) forControlEvents:UIControlEventEditingChanged];
[self loadUserData];
}
- (void) textChange{
self.LoginBtn.enabled = self.account.text.length && self.password.text.length;
}
- (IBAction)LoginClick {
NSString *account = self.account.text;
NSString *password = self.password.text;
if (![account isEqualToString:@"lx"]) {
return;
}
if (![password isEqualToString:@"123"]) {
return;
}
[self saveUserData];
[self.view endEditing:YES];
[self performSegueWithIdentifier:@"login" sender:nil];
}
- (void)loadUserData{
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
self.account.text = [defaults objectForKey:@"account"];
self.password.text = [defaults objectForKey:@"password"];
}
- (void)saveUserData{
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:self.account.text forKey:@"account"];
[defaults setObject:self.password.text forKey:@"password"];
[defaults synchronize];
}
@end
57.使用Preferences保存用户名和密码
原文：http://www.cnblogs.com/lixiang2015/p/4867297.html
