Getting OnLoad to work

[tsadok]

I'm converting my old XML file to Lua (something I don't understand to something I do). Here's the relevant code:

BGGeneral.primaryFrame = CreateFrame("Frame", "BGGMainFrame", UIParent)
BGGeneral.primaryFrame:EnableMouse(true)
BGGeneral.primaryFrame:SetMovable(true)
BGGeneral.primaryFrame:RegisterForDrag("LeftButton")
BGGeneral.primaryFrame:SetScript("OnLoad", BGGeneral.OnLoad)
BGGeneral.primaryFrame:SetScript("OnDragStart", function() self:StartMoving() end)
BGGeneral.primaryFrame:SetScript("OnDragStop", function()
    print("OnDragStop running...")
    self:StopMovingOrSizing()
    self.framePosX = self:GetLeft()
    self.framePosY = self:GetTop()
end)

The "OnLoad" and "OnDragStop" handlers never seem to execute. Am I missing something obvious? I can call BGGeneral.OnLoad() as the last statement in my last file, but that's not pretty or elegant.

[IBLJerry]

Originally Posted by tsadok The "OnLoad" and "OnDragStop" handlers never seem to execute. Am I missing something obvious? I can call BGGeneral.OnLoad() as the last statement in my last file, but that's not pretty or elegant.

OnLoad executes at Frame Creation, so you really can't set a OnLoad handler in lua. But that does not matter at all as you can simply call your function by hand.

Your OnDragStop doesn't get called because your OnDragStart handler is incorrect, and your Frame never gets dragged.

local f = CreateFrame("Frame", "BGGMainFrame", UIParent)
f:EnableMouse(true)
f:SetMovable(true)
f:RegisterForDrag("LeftButton")
-- f:SetScript("OnLoad", BGGeneral.OnLoad)
BGGeneral.OnLoad(f) -- let's just call it ourself

f:SetScript("OnDragStart", function(self) self:StartMoving() end)
f:SetScript("OnDragStop", function(self)
    print("OnDragStop running...")
    self:StopMovingOrSizing()
    self.framePosX = self:GetLeft()
    self.framePosY = self:GetTop()
end)
BGGeneral.primaryFrame = f

[Akryn]

I'm pretty sure I've done OnLoad successfully in Lua before, although now that I look I can't find an example of it..

Either way, note that

BGGeneral.primaryFrame:SetScript("OnLoad", BGGeneral.OnLoad)

will not work properly for any script unless BGGeneral.OnLoad is already defined at this point (i.e. higher in the file than this call) because SetScript passes the function itself to the frame which then keeps its own copy of it until you give it something else with another SetScript call.

Also, IBLJerry is correct that you need:

"OnDragStart", function(self)
"OnDragStop", function(self)

[tsadok]

Ah, of course, it evalutates BGGeneral.OnLoad at that point which is nil. The strange thing is that the frame would actually move. Maybe RegisterForDrag had something to do with that.

And no colon means I have to specify 'self'.

Thank you!

[tsadok]

I've been trying out the new code, and found that the problem was that I was using a Title Region. This let the frame be dragged whether or not it was set as moveable or registered for clicks or whatever. I've changed the title region to a normal region and the frame drags around as it should and runs its OnDragStart and OnDragStop handlers.

Given that the only documentation on Frame:CreateTitleRegion() all leads back to Slouken's post, it's probably worth giving a miss if you can get your main frame dragging properly anyway.

[Mera]

registerfordrag is not mandatory and rarely used