LayoutCollapseTest.lua

function CreateTestFrame(parent, text, color)
    local frame = CreateFrame("Frame", nil, parent)
    frame.Bg = frame:CreateTexture()
    frame.Bg:SetAllPoints(frame)
    frame.Bg:SetColorTexture(color:GetRGBA())
    frame.Text = frame:CreateFontString(nil, nil, "GameFontNormalHuge")
    frame.Text:SetAllPoints(frame)
    frame.Text:SetText(text)
    frame:SetCollapsesLayout(true)
    return frame
end

GridFrame = CreateTestFrame(nil, nil, CreateColor(1, 1, 1, 0.25))
GridFrame:SetPoint("CENTER")
GridFrame:SetSize(340, 340)

Cell1 = CreateTestFrame(GridFrame, "1", CreateColor(1, 0, 0, 0.5))
Cell1:SetPoint("TOPLEFT", 10, -10)
Cell1:SetSize(100, 100)

Cell2 = CreateTestFrame(GridFrame, "2", CreateColor(0, 1, 0, 0.5))
Cell2:SetPoint("LEFT", Cell1, "RIGHT", 10, 0)
Cell2:SetSize(100, 100)

Cell3 = CreateTestFrame(GridFrame, "3", CreateColor(0, 0, 1, 0.5))
Cell3:SetPoint("LEFT", Cell2, "RIGHT", 10, 0)
Cell3:SetSize(100, 100)

Cell4 = CreateTestFrame(GridFrame, "4", CreateColor(1, 0, 0, 0.5))
Cell4:SetPoint("TOP", Cell1, "BOTTOM", 0, -10)
Cell4:SetSize(100, 100)

Cell5 = CreateTestFrame(GridFrame, "5", CreateColor(0, 1, 0, 0.5))
Cell5:SetPoint("LEFT", Cell4, "RIGHT", 10, 0)
Cell5:SetSize(100, 100)

Cell6 = CreateTestFrame(GridFrame, "6", CreateColor(0, 0, 1, 0.5))
Cell6:SetPoint("LEFT", Cell5, "RIGHT", 10, 0)
Cell6:SetSize(100, 100)

Cell7 = CreateTestFrame(GridFrame, "7", CreateColor(1, 0, 0, 0.5))
Cell7:SetPoint("TOP", Cell4, "BOTTOM", 0, -10)
Cell7:SetSize(100, 100)

Cell8 = CreateTestFrame(GridFrame, "8", CreateColor(0, 1, 0, 0.5))
Cell8:SetPoint("LEFT", Cell7, "RIGHT", 10, 0)
Cell8:SetSize(100, 100)

Cell9 = CreateTestFrame(GridFrame, "9", CreateColor(0, 0, 1, 0.5))
Cell9:SetPoint("LEFT", Cell8, "RIGHT", 10, 0)
Cell9:SetSize(100, 100)