知识点总结11-通过改变约束实现滑出注册窗口

#import "ZGKLoginViewController.h"

@interface ZGKLoginViewController ()
// 立即登录按钮
@property (weak, nonatomic) IBOutlet UIButton *loginBtn;
// 登录模块左边间距
@property (weak, nonatomic) IBOutlet NSLayoutConstraint *leftMargin;

@end

@implementation ZGKLoginViewController

/**** 导航栏颜色 ****/
- (UIStatusBarStyle)preferredStatusBarStyle{
    return UIStatusBarStyleLightContent;
}
- (IBAction)closeBtn {
    [self dismissViewControllerAnimated:YES completion:nil];
}
- (IBAction)registerOrLoginBtn:(UIButton *)sender {
    
    // 1.关闭输入法
    [self.view endEditing:YES];

    
//    // 2.改变登录框的约束,记得改变左边的约束,不要固定死右边的约束
    if (self.leftMargin.constant) { // 这个里没有改变控件的frame,只是记录了要改变的约束,所以不能将这些代码放入动画中,要将强制刷新动作放入动画中
        // 目前显示的是注册界面,点击按钮后切换为登录界面
        self.leftMargin.constant = 0;
        sender.selected = NO;
        [sender setTitle:@"注册账号" forState:UIControlStateNormal];
    }else{ // 目前显示的是登录界面,点击按钮后切换为注册界面
        self.leftMargin.constant = self.view.zgk_width;
        sender.selected = YES;
        [sender setTitle:@"已有账号" forState:UIControlStateSelected];
    }
    
    // 3.做动画,强制刷新,或者等runloop也可以
    [UIView animateWithDuration:0.25 animations:^{
        // 这里会刷新self.view内部所有子控件的布局
        // 强制刷新:让最新设置的约束值马上作用到UI控件上
        [self.view layoutIfNeeded];
    }];
}

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
//    [self dismissViewControllerAnimated:YES completion:nil];
    // 点击空白地方,关闭输入法
    [self.view endEditing:YES];
}

- (void)viewDidLoad {
    [super viewDidLoad];

    // 设置圆角登录按钮
    // 数值前面要加@,包装成对象,直接属性用setValue forKey, 间接属性用setValue forKeyPath
    //    self.loginBtn.layer.cornerRadius = 5;
    [self.loginBtn setValue:@5 forKeyPath:@"layer.cornerRadius"];
    
    //    self.loginBtn.layer.masksToBounds = YES;
    [self.loginBtn setValue:@YES forKeyPath:@"layer.masksToBounds"];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

/*
#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
}
*/

@end

• 0.将登录窗口的左间距拖入到登录窗口(注意xib中,右间距不能设置死,最好不设置,不然滑动会出现问题)

// 登录模块左边间距
@property (weak, nonatomic) IBOutlet NSLayoutConstraint *leftMargin;

• 1.点击注册或者返回已有账号按钮

- (IBAction)registerOrLoginBtn:(UIButton *)sender {

    // 1.关闭输入法
    [self.view endEditing:YES];


   // 2.改变登录框的约束,记得改变左边的约束,不要固定死右边的约束
    if (self.leftMargin.constant) { // 这个里没有改变控件的frame,只是记录了要改变的约束,所以不能将这些代码放入动画中,要将强制刷新动作放入动画中
        // 目前显示的是注册界面,点击按钮后切换为登录界面
        self.leftMargin.constant = 0;
        sender.selected = NO;
        [sender setTitle:@"注册账号" forState:UIControlStateNormal];
    }else{ // 目前显示的是登录界面,点击按钮后切换为注册界面
        self.leftMargin.constant = self.view.zgk_width;
        sender.selected = YES;
        [sender setTitle:@"已有账号" forState:UIControlStateSelected];
    }
    // 3.做动画,强制刷新,或者不强制刷新等runloop也可以
    [UIView animateWithDuration:0.25 animations:^{
        // 这里会刷新self.view内部所有子控件的布局
        // 强制刷新:让最新设置的约束值马上作用到UI控件上
        [self.view layoutIfNeeded];
    }];
}

• 2.让登录按钮的方框角变成圆角

- (void)viewDidLoad {
    [super viewDidLoad];

    // 设置圆角登录按钮
    // 数值前面要加@,包装成对象,直接属性用setValue forKey, 间接属性用setValue forKeyPath
    //    self.loginBtn.layer.cornerRadius = 5; 
    
    // 方法二:kvc
    [self.loginBtn setValue:@5 forKeyPath:@"layer.cornerRadius"];

    //    self.loginBtn.layer.masksToBounds = YES;
    // 方法二:kvc
    [self.loginBtn setValue:@YES forKeyPath:@"layer.masksToBounds"];
}

• 3.xib中设置登录按钮的圆角半径和裁剪

  
  
  4104104C-877C-431A-927B-156D2915B705.png

• 4.成为第一响应者,并设置占位文字颜色

259D3EB5-7365-41B4-8EC2-17A0CAA84245.png

• 5.报错: storyboard中设置了错误的类

18631315-AF9C-4545-A28F-B0AB2E36384F.png