contain → const BoxFit
As large as possible while still containing the source entirely within the target box.
const BoxFit(1)As small as possible while still covering the entire target box.
const BoxFit(2)Fill the target box by distorting the source's aspect ratio.
const BoxFit(0)Make sure the full height of the source is shown, regardless of whether this means the source overflows the target box horizontally.
const BoxFit(4)Make sure the full width of the source is shown, regardless of whether this means the source overflows the target box vertically.
const BoxFit(3)Align the source within the target box (by default, centering) and discard any portions of the source that lie outside the box.
The source image is not resized.
const BoxFit(5)Align the source within the target box (by default, centering) and, if necessary, scale the source down to ensure that the source fits within the box.
This is the same as contain if that would shrink the image, otherwise it is the same as none.
const BoxFit(6)
![[转]Xvid参数详解](http://pic.xiahunao.cn/[转]Xvid参数详解)
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