1.Masonry的屬性
@property (nonatomic,strong,readonly)MASConstraint *left; //左側
@property(nonatomic,strong,readonly) MASConstraint *top;//上側
@property(nonatomic,strong,readonly)MASConstraint*right;//右側
@property(nonatomic,strong,readonly)MASConstraint*bottom;?//下側
@property(nonatomic,strong,readonly)MASConstraint*leading;?//首部
@property(nonatomic,strong,readonly) MASConstraint *trailing;?//尾部
@property(nonatomic, strong, readonly) MASConstraint *width;???//寬
@property (nonatomic, strong, readonly) MASConstraint *height; ?//高
@property(nonatomic, strong, readonly)MASConstraint *centerX;?//橫向居中
@property(nonatomic, strong,readonly)MASConstraint *centerY;? //縱向居中
@property (nonatomic, strong, readonly) MASConstraint *baseline; //文本基線
2.Masonry給我們提供了3個方法
//新增約束
- (NSArray *)mas_makeConstraints:(void(^)(MASConstraintMaker *make))block;
//更新約束
- (NSArray *)mas_updateConstraints:(void(^)(MASConstraintMaker *make))block;
//清楚之前的所有約束,只會保留最新的約束
- (NSArray *)mas_remakeConstraints:(void(^)(MASConstraintMaker *make))block;
3.常見約束的各種類型
1.尺寸：width休偶、height韭邓、size
2.邊界：left姐叁、leading衅胀、right曹仗、trailing纸巷、top粥喜、bottom
3.中心點：center乘凸、centerX、centerY
4.邊界：edges
5.偏移量：offset党远、insets削解、sizeOffset、centerOffset
6.priority()約束優(yōu)先級（0~1000）沟娱，multipler乘因數, dividedBy除因數
4.Masonry約束易忽略的技術點
使用Masonry不需要設置控件的translatesAutoresizingMaskIntoConstraints屬性為NO;
防止block中的循環(huán)引用氛驮，使用弱引用（這是錯誤觀點），在這里block是局部的引用济似，block內部引用self不會造成循環(huán)引用的
__weak typeof (self) weakSelf = self;（沒必要的寫法）
5.Masonry約束控件出現沖突的問題
當約束沖突發(fā)生的時候矫废，我們可以設置view的key來定位是哪個view
redView.mas_key = @"redView";
greenView.mas_key = @"greenView";
blueView.mas_key = @"blueView";
若是覺得這樣一個個設置比較繁瑣盏缤，怎么辦呢，Masonry則提供了批量設置的宏MASAttachKeys
MASAttachKeys(redView,greenView,blueView); //一句代碼即可全部設置
6.equalTo和mas_equalTo的區(qū)別
mas_equalTo只是對其參數進行了一個BOX(裝箱) 操作蓖扑，目前支持的類型：數值類型（NSNumber）唉铜、 點（CGPoint）、大新筛堋（CGSize）潭流、邊距（UIEdgeInsets），而equalTo：這個方法不會對參數進行包裝柜去。
7.Masonry布局
make.top.equalTo(view).with.offset(10);// 距離上10
make.left.equalTo(view).with.offset(10);//距離左10
make.bottom.equalTo(view).with.offset(-10);//距離下10
make.right.equalTo(view).with.offset(-10);//距離右10
等同于make.edges.mas_offset(UIEdgeInsetsMake(10,10,10,10));
等高 \等寬
make.height.mas_equalTo(@[redView, blueView]);
make.width.mas_equalTo(@[redView, blueView]);
最大值
make.width.height.lessThanOrEqualTo(@250);
最大放大到整個view make.width.height.lessThanOrEqualTo(self.view);
最小值make.width.height.greaterThanOrEqualTo(@90);
優(yōu)先級最低
make.width.height.mas_equalTo(100 * self.scacle).priorityLow();
設置高/寬為3:1,要求是同一個控件的屬性比例
make.height.mas_equalTo(bottomInnerView.mas_width).multipliedBy(3);
*? axisType???????? 軸線方向
*? fixedSpacing???? 間隔大小
*? fixedItemLength? 每個控件的固定長度/寬度
*? leadSpacing????? 頭部間隔
*? tailSpacing????? 尾部間隔
//首先添加5個視圖
NSMutableArray *array = [NSMutableArray new];
for (int i = 0; i < 5; i ++) {
UIView *view = [UIView new];
view.backgroundColor = [UIColor greenColor];
[self addSubview:view];
[array addObject:view]; //保存添加的控件
}
水平方向控件間隔固定等間隔
[array mas_distributeViewsAlongAxis:MASAxisTypeHorizontal withFixedSpacing:15 leadSpacing:10 tailSpacing:10];
[array makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(50);
make.height.equalTo(70);
}];
水平方向寬度固定等間隔
[array mas_distributeViewsAlongAxis:MASAxisTypeHorizontal withFixedItemLength:70 leadSpacing:10 tailSpacing:10];
[array makeConstraints:^(MASConstraintMaker *make) { //數組額你不必須都是view
make.top.equalTo(50);
make.height.equalTo(70);
}];
設置preferredMaxLayoutWidth:多行label約束的完美解決
[self.label makeConstraints:^(MASConstraintMaker *make) {
make.left.top.equalTo(10);
make.right.equalTo(-10);
}];
更新約束 mas_updateConstraints
// 告訴self.view約束需要更新
[self.view setNeedsUpdateConstraints];
// 調用此方法告訴self.view檢測是否需要更新約束灰嫉，若需要則更新，下面添加動畫效果才起作用
[self.view updateConstraintsIfNeeded];
[UIView animateWithDuration:0.3 animations:^{
[self.view layoutIfNeeded];
}];
- (void)updateViewConstraints {
[self.growingButton mas_updateConstraints:^(MASConstraintMaker *make) { }];
[super updateViewConstraints];
}
