iOS之Masonry快速上手

快速上手

1.简介

Masonry是一个轻量级的布局框架，拥有自己的描述语法，采用更优雅的链式语法封装自动布局，同时支持 iOS 和 Max OS X。Masonry是一个用代码写iOS或OS界面的库，可以代替Auto layout。
Masonry的github地址：Masonry!

2.配置

推荐使用pods方式引入类库，pod ‘Masonry’，若不知道pod如何使用，自行谷歌
引入头文件 #import “Masonry.h”

3.规则

mas_makeConstraints 是给view添加约束，约束有几种，分别是边距，宽，高，左上右下距离，基准线。添加过约束后可以有修正，修正有offset（位移）修正和multipliedBy（倍率）修正。
语法一般是 make.equalTo or make.greaterThanOrEqualTo or make.lessThanOrEqualTo + 倍数和位移修正。

4.注意点

使用 mas_makeConstraints方法的元素必须事先添加到父元素的中，例如[self.view addSubview:view];
masequalTo 和 equalTo 区别：
masequalTo 比 qualTo 多了类型转换操作，一般来说，大多数时候两个方法都是通用的，但是对于数值元素使用mas_equalTo。对于对象或是多个属性的处理，使用equalTo。特别是多个属性时，必须使用equalTo,例如 make.left.and.right.equalTo(self.view);

5.实例

// exp1: 中心点与self.view相同，宽度为400*400
-(void)exp1{
    UIView *view = [UIView new];
    [view setBackgroundColor:[UIColor redColor]];
    [self.view addSubview:view];
    [view mas_makeConstraints:^(MASConstraintMaker *make) {
         make.center.equalTo(self.view);
         make.size.mas_equalTo(CGSizeMake(400,400));
    }];
}
//exp2: 上下左右边距都为10
-(void)exp2{
    UIView *view = [UIView new];
    [view setBackgroundColor:[UIColor redColor]];
    [self.view addSubview:view];
    [view mas_makeConstraints:^(MASConstraintMaker *make) {
        make.edges.equalTo(self.view).with.insets(UIEdgeInsetsMake(10, 10, 10, 10));
        //  make.left.equalTo(self.view).with.offset(10);
        //  make.right.equalTo(self.view).with.offset(-10);
        //  make.top.equalTo(self.view).with.offset(10);
        //  make.bottom.equalTo(self.view).with.offset(-10);
    }];
}
//exp3 让两个高度为150的view垂直居中且等宽且等间隔排列 间隔为10
-(void)exp3{
    UIView *view1 = [UIView new];
    [view1 setBackgroundColor:[UIColor redColor]];
    [self.view addSubview:view1];
    UIView *view2 = [UIView new];
    [view2 setBackgroundColor:[UIColor redColor]];
    [self.view addSubview:view2];
    [view1 mas_makeConstraints:^(MASConstraintMaker *make) {
        make.centerY.mas_equalTo(self.view.mas_centerY);
        make.height.mas_equalTo(150);
        make.width.mas_equalTo(view2.mas_width);
        make.left.mas_equalTo(self.view.mas_left).with.offset(10);
        make.right.mas_equalTo(view2.mas_left).offset(-10);
    }];
    [view2 mas_makeConstraints:^(MASConstraintMaker *make) {
        make.centerY.mas_equalTo(self.view.mas_centerY);
        make.height.mas_equalTo(150);
        make.width.mas_equalTo(view1.mas_width);
        make.left.mas_equalTo(view1.mas_right).with.offset(10);
        make.right.equalTo(self.view.mas_right).offset(-10);
    }];
}

详细介绍(简单属性不再介绍,不会可查字典)

1.基本属性(Attribute)

@property (nonatomic, strong, readonly) MASConstraint left;
@property (nonatomic, strong, readonly) MASConstraint top;
@property (nonatomic, strong, readonly) MASConstraint right;
@property (nonatomic, strong, readonly) MASConstraint bottom;
@property (nonatomic, strong, readonly) MASConstraint leading; 左
@property (nonatomic, strong, readonly) MASConstraint trailing; 右
@property (nonatomic, strong, readonly) MASConstraint width;
@property (nonatomic, strong, readonly) MASConstraint height;
@property (nonatomic, strong, readonly) MASConstraint centerX;
@property (nonatomic, strong, readonly) MASConstraint centerY;
@property (nonatomic, strong, readonly) MASConstraint *baseline; 基线

#if (IPHONE_OS_VERSION_MIN_REQUIRED >= 80000) || (TV_OS_VERSION_MIN_REQUIRED >= 9000) || (__MAC_OS_X_VERSION_MIN_REQUIRED >= 101100)

@property (nonatomic, strong, readonly) MASConstraint firstBaseline;
@property (nonatomic, strong, readonly) MASConstraint lastBaseline;

#endif

#if TARGET_OS_IPHONE || TARGET_OS_TV

@property (nonatomic, strong, readonly) MASConstraint leftMargin;
@property (nonatomic, strong, readonly) MASConstraint rightMargin;
@property (nonatomic, strong, readonly) MASConstraint topMargin;
@property (nonatomic, strong, readonly) MASConstraint bottomMargin;
@property (nonatomic, strong, readonly) MASConstraint leadingMargin;
@property (nonatomic, strong, readonly) MASConstraint trailingMargin;
@property (nonatomic, strong, readonly) MASConstraint centerXWithinMargins;
@property (nonatomic, strong, readonly) MASConstraint centerYWithinMargins;

可参考下图学习
Alt text

2.Constant

(MASConstraint * (^)(MASEdgeInsets insets))insets; 与四边边距
(MASConstraint * (^)(CGSize offset))sizeOffset;
(MASConstraint * (^)(CGPoint offset))centerOffset;
(MASConstraint * (^)(CGFloat offset))offset; —- 位移
(MASConstraint (^)(NSValue value))valueOffset; —- 以上值的组合

3.Multiplier(倍率)

(MASConstraint * (^)(CGFloat multiplier))multipliedBy; 与dividedBy互为倒数,方便计算

(MASConstraint * (^)(CGFloat divider))dividedBy;

4.Priority(优先级)

(MASConstraint * (^)(MASLayoutPriority priority))priority;
(MASConstraint * (^)())priorityLow;
(MASConstraint * (^)())priorityMedium;

(MASConstraint * (^)())priorityHigh;

5.intrinsicContentSize

(CGSize)intrinsicContentSize; — 默认尺寸大小
(void)invalidateIntrinsicContentSize — 使默认尺寸大小失效后重新计算

6.ContentPriority

(UILayoutPriority)contentHuggingPriorityForAxis:(UILayoutConstraintAxis)axis NS_AVAILABLE_IOS(6_0);
(void)setContentHuggingPriority:(UILayoutPriority)priority forAxis:(UILayoutConstraintAxis)axis NS_AVAILABLE_IOS(6_0);
(UILayoutPriority)contentCompressionResistancePriorityForAxis:(UILayoutConstraintAxis)axis NS_AVAILABLE_IOS(6_0);
(void)setContentCompressionResistancePriority:(UILayoutPriority)priority forAxis:(UILayoutConstraintAxis)axis NS_AVAILABLE_IOS(6_0);

可参考下图理解
Alt text