KeepLayout 项目教程

KeepLayout 项目教程

KeepLayoutMaking Auto Layout easier to code.项目地址:https://gitcode.com/gh_mirrors/ke/KeepLayout

1. 项目的目录结构及介绍

KeepLayout 项目的目录结构如下：

KeepLayout/
├── KeepLayout.podspec
├── LICENSE.md
├── README.md
├── UIViewController+KeepLayout.h
├── UIViewController+KeepLayout.m
├── UIView+KeepLayout.h
├── UIView+KeepLayout.m
├── KeepLayoutConstraint.h
├── KeepLayoutConstraint.m
├── KeepValue.h
├── KeepValue.m
├── NSArray+KeepLayout.h
├── NSArray+KeepLayout.m
├── KeepView.h
└── KeepView.m

目录结构介绍

• KeepLayout.podspec: 项目的 Podspec 文件，用于 CocoaPods 集成。
• LICENSE.md: 项目的许可证文件，采用 MIT 许可证。
• README.md: 项目的说明文档。
• UIViewController+KeepLayout.h 和 UIViewController+KeepLayout.m: 扩展 UIViewController，添加 KeepLayout 功能。
• UIView+KeepLayout.h 和 UIView+KeepLayout.m: 扩展 UIView，添加 KeepLayout 功能。
• KeepLayoutConstraint.h 和 KeepLayoutConstraint.m: 自定义 NSLayoutConstraint 子类，用于 KeepLayout。
• KeepValue.h 和 KeepValue.m: 定义 KeepValue 类型，用于布局属性。
• NSArray+KeepLayout.h 和 NSArray+KeepLayout.m: 扩展 NSArray，添加 KeepLayout 功能。
• KeepView.h 和 KeepView.m: 提供 KeepLayout 的视图相关功能。

2. 项目的启动文件介绍

KeepLayout 项目的启动文件是 UIViewController+KeepLayout.h 和 UIViewController+KeepLayout.m，以及 UIView+KeepLayout.h 和 UIView+KeepLayout.m。这些文件通过类别（Category）扩展了 UIViewController 和 UIView，添加了 KeepLayout 功能。

UIViewController+KeepLayout.h

#import <UIKit/UIKit.h>

@interface UIViewController (KeepLayout)

@property (readonly) UIView *keepLayoutView;

@end

UIViewController+KeepLayout.m

#import "UIViewController+KeepLayout.h"
#import "KeepLayoutConstraint.h"

@implementation UIViewController (KeepLayout)

- (UIView *)keepLayoutView {
    UIView *layoutView = objc_getAssociatedObject(self, @selector(keepLayoutView));
    if (!layoutView) {
        layoutView = [[UIView alloc] initWithFrame:CGRectZero];
        layoutView.translatesAutoresizingMaskIntoConstraints = NO;
        [self.view addSubview:layoutView];
        
        // 添加约束
        [self.view addConstraints:@[
            [KeepLayoutConstraint constraintWithItem:layoutView attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:self.topLayoutGuide attribute:NSLayoutAttributeBottom multiplier:1 constant:0],
            [KeepLayoutConstraint constraintWithItem:layoutView attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:self.bottomLayoutGuide attribute:NSLayoutAttributeTop multiplier:1 constant:0],
            [KeepLayoutConstraint constraintWithItem:layoutView attribute:NSLayoutAttributeLeft relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeLeft multiplier:1 constant:0],
            [KeepLayoutConstraint constraintWithItem:layoutView attribute:NSLayoutAttributeRight relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeRight multiplier:1 constant:0]
        ]];
        
        objc_setAssociatedObject(self, @selector(keepLayoutView), layoutView, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    }
    return layoutView;
}

@end

UIView+KeepLayout.h

#import <UIKit/UIKit.h>

@interface UIView (KeepLayout)

@property (readonly) KeepAttribute *keepWidth;
@property (readonly) KeepAttribute *keepHeight;
@property (readonly) KeepAttribute *(^keepTopOffsetTo)(UIView *);
@property (readonly) KeepAttribute *(^keepLeftOffsetTo)(UIView *);
@property (readonly) KeepAttribute *(^keepBottomOffsetTo)(UIView *);

KeepLayoutMaking Auto Layout easier to code.项目地址:https://gitcode.com/gh_mirrors/ke/KeepLayout