iOS UICollectionView等分有1px缝隙

https://www.jianshu.com/p/01cadd95604d

参考网上的文章

- (CGFloat)fixSlitWith:(CGRect)rect colCount:(CGFloat)colCount space:(CGFloat)space { CGFloat totalSpace = (colCount - 1) * space;//总共留出的距离 CGFloat itemWidth = (rect.size.width - totalSpace) / colCount;// 按照真实屏幕算出的cell宽度 （iPhone6 375*667）93.75 CGFloat fixValue = 1 / [UIScreen mainScreen].scale; //(1px=0.5pt,6Plus为3px=1pt) CGFloat realItemWidth = floor(itemWidth) + fixValue;//取整加fixValue floor:如果参数是小数，则求最大的整数但不大于本身. if (realItemWidth < itemWidth) {// 有可能原cell宽度小数点后一位大于0.5 realItemWidth += fixValue; } CGFloat realWidth = colCount * realItemWidth + totalSpace;//算出屏幕等分后满足1px=([UIScreen mainScreen].scale)pt实际的宽度,可能会超出屏幕,需要调整一下frame CGFloat pointX = (realWidth - rect.size.width) / 2; //偏移距离 rect.origin.x = -pointX;//向左偏移 rect.size.width = realWidth; _rect = rect; return realItemWidth; //每个cell的真实宽度}

得到cell/线的宽度