I also posted an article about introduction to Compositional Layout. You can read here: https://medium.com/@tungvuduc2805/compositional-layout-in-uicollectionview-432f942249b6
Images source: https://unsplash.com/
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// | +-------------------------------+ +-----------+ |
// | | | | | |
// | | | | | |
// | | | | 1 | |
// | | | | | |
// | | | +-----------+ |
// | | 0 | |
// | | | +-----------+ |
// | | | | | |
// | | | | | |
// | | | | 2 | |
// | | | | | |
// | +-------------------------------+ +-----------+. |
// | +--------------+----------------+--------------+ |
// | | | | | |
// | | 1 | 2 | 3 | |
// | | | | | |
// | | | | | |
// | +--------------+----------------+--------------+ |
// | +--------------+----------------+--------------+ |
// | | | | | |
// | | 4 | 5 | 6 | |
// | | | | | |
// | | | | | |
// | +--------------+----------------+--------------+ |
// | +--------------+ +----------------------------+ |
// | | | | | |
// | | 1 | | | |
// | | | | | |
// | | | | | |
// | +--------------+ | | |
// | | 0 | |
// | +--------------+ | | |
// | | | | | |
// | | 2 | | | |
// | | | | | |
// | | | | | |
// | +--------------+ +----------------------------+ |
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