双向滑动，滑块可以重叠, 左边滑块不能移动到右边滑块的右边。Two slider can overlap, and the left slider can not be moved to right of the right slider
示例
增加了最小间隙
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anonymity-du/DoubleSliderView-Objective-C
双向滑动，滑块可以重叠, 左边滑块不能移动到右边滑块的右边。Two slider can overlap, and the left slider can not be moved to right of the right slider
Objective-C