UIView循环排列

项目中可能会遇到的一种排版方式，见图

0C9007B3-B911-4D04-8366-83560D738B8E.png

废话少说，直接上代码

UIView *bgView = [[UIView alloc] initWithFrame:CGRectMake(20, 100, 300, 300)];
bgView.backgroundColor = [UIColor colorWithRed:0 green:0 blue:0 alpha:0.05];
[self.view addSubview:bgView];

for (int i = 1; i<=9; i++) {
    CGFloat width = 60;
    CGFloat height = 60;
    CGFloat spaceW = 10.0;
    
    UIView *view = [UIView new];
    view.frame = CGRectMake(0, 0, width, height);
    view.backgroundColor = [self randomColor];
    [bgView addSubview:view];
    
    // X = (当前下标-1)%每行显示数量*宽度 + (当前下标-1)%每行显示数量*间隙 + 间隙
    CGFloat x = (i-1)%4*width + (i-1)%4*spaceW + spaceW;
    
    // Y = (当前下标-1)/每行显示数量*高度 + (当前下标-1)/每行显示数量*间隙 + 间隙
    CGFloat y = (i-1)/4*height + (i-1)/4*spaceW + spaceW;
    view.frame = CGRectMake(x, y, width, height);
}


- (UIColor *)randomColor
{
    CGFloat hue = ( arc4random() % 256 / 256.0 ); //0.0 to 1.0
    CGFloat saturation = ( arc4random() % 128 / 256.0 ) + 0.5; // 0.5 to 1.0,away from white
    CGFloat brightness = ( arc4random() % 128 / 256.0 ) + 0.5; //0.5 to 1.0,away from black
    return [UIColor colorWithHue:hue saturation:saturation brightness:brightness alpha:1];
}