• 1.效果图：

1.png

• 2.计算思路：

2.png

• 3.代码：

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor orangeColor];
  
    [self setupButton];
}
- (void)setupButton{
    int totalloc = 4;//一行的列数
    CGFloat appViewW = 80; //按钮的宽度
    CGFloat appViewH = 80; //按钮的高度
   //间隙= （整个屏幕的宽度-总列数*每个的宽度）/（总列数+1）即间隙
    CGFloat margin = (self.view.frame.size.width-appViewW*totalloc)/(totalloc+1);
    
    int count = 4; //总按钮的数量 
    for(int i = 0 ; i<count;i++){
        int row = i/totalloc;//行号
        int loc = i%totalloc;//列号   
        CGFloat appViewX = margin + (margin + appViewW) * loc; //x值由列号决定  
        CGFloat appViewY = margin + (margin + appViewW) * row;  //x值由行号决定

     UIButton *btn =[UIButton buttonWithType:UIButtonTypeCustom];
        btn.frame = CGRectMake(appViewX, appViewY, appViewW, appViewH);
        btn.backgroundColor = [UIColor redColor];
        [self.view addSubview:btn];
    }  
}