Xcode9 app icon需要哪些尺寸

OS app icon有各种不同的尺寸，包括不同机型，不同类型！可以参考下下面：
Device/Screen    File Name (PNG)    Icon Size (pixels)    
iPhone and iPod    
Application Icon for iPhone (retina display)    Icon@2x.png    114 x 114    
Application Icon icon for iPhone    Icon.png    57 x 57    
Settings/Spotlight icon for iPhone (retina display)    Icon-Small@2x.png    58 x 58    
Settings/Spotlight icon for iPhone    Icon-Small.png    29 x 29    
Launch image Portrait (retina display)    Default@2x.png    640 x 960    
Launch image Portrait    Default.png    320 x 480    
iPad    
Application Icon for the new iPad (retina display)    Icon-72@2x.png    144 x 144    
Application Icon for the iPad    Icon-72.png    72 x 72    
Settings/Spotlight icon for iPad    Icon-Small-50@2x.png    100 x 100    
Settings/Spotlight icon for iPad    Icon-Small-50.png    50 x 50    
Launch image Portrait (retina display)    Default-Portrait@2x.png    1536 x 2048    
Launch image Portrait    Default-Portrait.png    768 x 1004    
Launch image Landscape (retina display)    Default-Landscape@2x.png    2048 x 1536    
Launch image Landscape    Default-Landscape.png    1024 x 748    
iTunes App Store    
App icon for the App Store (retina display)    iTunesArtwork@2x.png    1024 x 1024    (不能为透明的，无透明色)
App icon for the App Store    iTunesArtwork.png    512 x 512