ios九宫格算法

- (void)viewDidLoad {
    [super viewDidLoad];
    //1.总列数(一行最多3列)
    int totalColumns=3;
    CGFloat appW=50;
    CGFloat appH=50;
    //2.间隙=(控制器的view的宽度-3*应用宽度)/4
    CGFloat margin=(self.view.frame.size.width-totalColumns*appW)/(totalColumns+1);
    //3.根据应用个数创建对应的框
    for (int index=0; index<self.apps.count; index++) {
        //NSDictionary *dict=self.apps[index];//字典
        //appModel *model=self.apps[index];//模型
        //创建一个view
        UIView *appView=[[UIView alloc] init];
        //设置背景色
        appView.backgroundColor=[UIColor redColor];
        //计算出行号和列号
        int row=index/totalColumns;
        int col=index%totalColumns;
        //每个格的坐标
        CGFloat appX=margin+col * (appW+margin);
        CGFloat appY=30+row*(appH + margin);
        appView.frame=CGRectMake(appX, appY, appW, appH);
        
        [self.view addSubview:appView];
    }
}