iOS:制作九宫格

 制作简单的九宫格：

源码如下：

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    //创建九宫格
    NSInteger col = 3;  //每行几列
    NSInteger total = 9;//总个数
    
    //格子的宽度、高度
    UIImage *image = [UIImage imageNamed:@"0.png"];
    CGFloat cellWidth = image.size.width;
    CGFloat cellHeight = image.size.height;
    
    CGFloat screenWidth = self.view.frame.size.width;
    
    CGFloat gapX = (screenWidth-cellWidth*col)/(col+1);//x方向的间隔
    CGFloat gapY = gapX;//y方向的间隔
    
    
    //计算行数
    NSInteger row = 0;
    
    for(int i=0; i<total; i++)
    {
        UIButton *button = [[UIButton alloc]init];
        [button setBackgroundImage:[UIImage imageNamed:[NSString stringWithFormat:@"%d.png",i]] forState:UIControlStateNormal];
        
        //计算是否需要换行
        if(i%col == 0)
        {
            row++;
        }
        CGFloat x = gapX+(cellWidth+gapX)*(i%col);
        CGFloat y = gapY+(cellHeight+gapY)*row;
        button.frame = CGRectMake(x, y, cellWidth, cellHeight);
        
        [self.view addSubview:button];
    }
}

@end