love-luigi/luigi/widget/sash.lua

local Widget = require((...):gsub('%.[^.]*$', ''))

local Sash = Widget:extend()

function Sash:constructor(layout, data)
    Widget.constructor(self, layout, data)

    self:onPressDrag(function(event)
        local axis = self.parent.flow
        if axis == 'x' then
            dimension = 'width'
        else
            axis = 'y'
            dimension = 'height'
        end
        local prevSibling = self:getPrevious()
        local nextSibling = self:getNext()
        local prevSize = prevSibling and prevSibling[dimension]
        local nextSize = nextSibling and nextSibling[dimension]
        if prevSize then
            prevSibling:setDimension(dimension,
                    event[axis] - prevSibling:calculatePosition(axis))
        end
        if nextSize then
            nextSibling:setDimension(dimension,
                    nextSibling:calculatePosition(axis) +
                    nextSibling[dimension] - event[axis])
        end

        layout:update(true)
    end)

end

return Sash