iOS UI-九宫格

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    // 设置每行应用的个数
    int clumns = 3;
    // 获取控制器所管理的view的宽度
    CGFloat viewWidth = self.view.frame.size.width;
    
    // 每个应用的宽和高
    CGFloat appW = 75;
    CGFloat appH = 90;
    CGFloat marginTop = 30;//第一行距顶部的距离
    CGFloat marginX = (viewWidth - appW*clumns)/(clumns+1);
    CGFloat marginY = marginX;//设每行之间的间距与marginX相等
    
    for (int i=0; i<9; i++) {
        //1.创建每个应用（UIView）
        UIView *appView = [[UIView alloc] init];
        
        //2.设置appView的属性
        
        //2.1设置appView的背景色
        appView.backgroundColor = [UIColor orangeColor];
        //2.2设置appView的frame属性
        
        //计算每个单元格的列索引
        int colIdx = i%clumns;
        //计算每个单元格的行索引
        int rowIdy = i/clumns;
        
        CGFloat appX = marginX+(appW+marginX)*colIdx;
        CGFloat appY = marginTop+(appH+marginY)*rowIdy;
        
        appView.frame = CGRectMake(appX, appY, appW, appH);
        
        //3.将appView加到self.view
        [self.view addSubview:appView];
        
    }
}