Masonry

實(shí)例化 redView 和 blueView

//實(shí)例化一個(gè)view

    UIView *redView = [[UIView alloc]init];
    
    redView.backgroundColor = [UIColor redColor];
    
    [self.view addSubview:redView];
    
    UIView *blueView = [[UIView alloc]init];
    
    blueView.backgroundColor = [UIColor blueColor];
    
    [self.view addSubview:blueView];

//masonry自動幫我們把a(bǔ)utoresizing給禁用掉

設(shè)置 redView 和 blueView 的約束

//  設(shè)置redView的約束
    
    [redView mas_makeConstraints:^(MASConstraintMaker *make) {
    
        // make.top.left.offset(20);
        
        // 針對topLayoutGuide進(jìn)行設(shè)置
        
        // self.mas_bottomLayoutGuide 設(shè)置底部
        
        // self.mas_topLayoutGuideBottom 設(shè)置頂部
        
        make.top.equalTo(self.mas_topLayoutGuideBottom);
        
        make.left.offset(20);
        
        make.right.offset(20);
        
        make.height.equalTo(@40);
        
    }];
    
    //  設(shè)置blueView的約束
    
    /*
     
     dividedBy: 除以
     
     multipledBy：乘以
     
     */
    
    [blueView mas_makeConstraints:^(MASConstraintMaker *make) {
       
        make.top.equalTo(redView.mas_bottom).offset(20);
        
        make.right.offset(-20);
        
        make.height.equalTo(redView);
        
        //  寬度
        
        //  make.width.equalTo(redView).multipliedBy(0.5);
        
        make.width.equalTo(redView).dividedBy(2);
        
    }];

更新約束

 //  更新約束
    
    [redView mas_updateConstraints:^(MASConstraintMaker *make) {
        
        //  更新redView的約束高度變?yōu)?0
        
        make.height.equalTo(@80);
        
    }];

重新設(shè)置約束

//  重新設(shè)置，會把之前的約束給清空掉，然后使用新的約束
    [redView mas_remakeConstraints:^(MASConstraintMaker *make) {
       
        make.top.left.offset(20);
        
        make.right.offset(-20);
        
        make.height.equalTo(@80);
        
    }];

設(shè)置約束的優(yōu)先級

//  設(shè)置約束的優(yōu)先級
    [redView mas_makeConstraints:^(MASConstraintMaker *make) {
        
        make.top.left.offset(20);
        
        make.right.offset(-20);
        
        make.height.equalTo(@40).priority(10);
        
    }];
    
    /*
     
     priority: 可以設(shè)置任意的優(yōu)先級，接受的參數(shù)是0-1000的數(shù)字
     priorityLow: 設(shè)置低優(yōu)先級，優(yōu)先級為250
     priorityMedium: 設(shè)置中優(yōu)先級，優(yōu)先級為500
     priorityHigh: 設(shè)置高優(yōu)先級，優(yōu)先級為750
     
     需要注意的是，使用priorityLow、priorityMedium、priorityHigh的時(shí)候。不是.priorityHigh，而是.priorityHigh()
     
     */