[Solved] Error: Attempt to call method 'Bang' (a nil value)

[Nooby4Ever]

Hallo

This appears in the rainmeter about - log console

Code: Select all

Error Script: Battery.lua:30: attempt to call method 'Bang' (a nil value)

It's my first time i try lua script and i'm stuck with this error, my code:

Code: Select all

PROPERTIES = {}
	-- Prefixes, not a part of the syntax:
	-- s(string)
	-- i(integer/number)
	-- ms(measure)
	-- mt(meter)
	-- t(table)
	
function Initialize()

	msPowerPercent = SKIN:GetMeasure("mPowerPercent")
	msPowerSource = SKIN:GetMeasure("mPowerSource")
	
	meter1 = SKIN:GetMeter("meterBGIcon7")
	meter2 = SKIN:GetMeter("meterBattGraph")
	
end

function Update()
	iPowerPercent = msPowerPercent:GetValue()
	sPowerSource = msPowerSource:GetStringValue()
	
	if sPowerSource == "Battery" then
		if iPowerPercent <= 10 then 
			meter1:Bang("!SetVariable ImageName BatteryOut.png")
		else 
			meter1:Bang("!SetVariable ImageName Battery.png")
		end
	else
		meter1:Bang("!SetVariable ImageName BatteryPlug.png")
	end
	
	meter1:Bang("!Refresh")	
		
	if iPowerPercent <=10 then 	   meter2:Bang("!SetVariable BarColor 0,92,0,255")
    elseif iPowerPercent <=30 then meter2:Bang("!SetVariable BarColor 92,0,0,255")
    elseif iPowerPercent <=50 then meter2:Bang("!SetVariable BarColor 0,0,92,255")
    elseif iPowerPercent <=70 then meter2:Bang("!SetVariable BarColor 11,92,0,255")
    elseif iPowerPercent <=90 then meter2:Bang("!SetVariable BarColor 0,92,11,255")
    else                 		   meter2:Bang("!SetVariable BarColor 125,92,48,255")
    end
	
	meter2:Bang("!Refresh")		
	
	return iPowerPercent	
end

The error is called on line 30, that would be meter1:Bang("!SetVariable ImageName BatteryPlug.png") (which is the line the script should come to with the current measures in my skin).

What did i do wrong?
(Running rainmeter 2.20 r1116 64bit)

[smurfier]

The Bang command does not work that way.

The correct usage is: SKIN:Bang('!SetVariable ImageName BatteryPlug.png')

If you're trying to change the ImageName of meterBGIcon7, then it's:
SKIN:Bang('!SetOption meterBGIcon7 ImageName BatteryPlug.png')

[Nooby4Ever]

The Bang command does not work that way.

The correct usage is: SKIN:Bang('!SetVariable ImageName BatteryPlug.png')

If you're trying to change the ImageName of meterBGIcon7, then it's:
SKIN:Bang('!SetOption meterBGIcon7 ImageName BatteryPlug.png')

Indeed that was my intention, thanks.
So just to make sure i get it right, SKIN is a static variable initilized by "rainmeter" itself that hold the current skin name/path/whatever.

I see were i gone wrong , i got this from the website:

Code: Select all

anyMeter = SKIN:GetMeter("ExampleMeter")
anyMeter:SetX(25)

But (now i saw it again) it indeed doesn't work for Bangs
Should have found this out myself, and i had used " instad of '

[jsmorley]

Indeed that was my intention, thanks.
So just to make sure i get it right, SKIN is a static variable initilized by "rainmeter" itself that hold the current skin name/path/whatever.

I see were i gone wrong , i got this from the website:

Code: Select all

anyMeter = SKIN:GetMeter("ExampleMeter")
anyMeter:SetX(25)

But (now i saw it again) it indeed doesn't work for Bangs
Should have found this out myself, and i had used " instad of '

Without delving too deep into the innards of how Lua works under the covers, It probably isn't good to think of SKIN as a "variable" in this case (or anyMeter in the example either for that matter) as they really are not. They are more like "objects" and the things after the ":" (like SKIN:Bang() or anyMeter:SetX()) are more like "methods". The SKIN object does indeed represent the skin that called the lua script, but be careful not to try to use it like a variable, you will just get some "handle" to the object.

[Nooby4Ever]

Ok thanks for the explaination (my word choice was indeed not very good, not that i knew it's an "object", i ment more a sort of sytax word as print but without doing something just pointing to the skin)

[jsmorley]

Ok thanks for the explaination (my word choice was indeed not very good, not that i knew it's an "object", i ment more a sort of sytax word as print but without doing something just pointing to the skin)

Fair enough, and my syntax is not meant to be technically literally correct either. I just wanted to point out that at least for me, thinking of those things as objects and methods for those objects helps me keep what is going on a bit clearer in my own head. It is sorta consistent with how the real geeks (I exclude myself) describe "object oriented" in the context of Lua.

http://www.lua.org/pil/16.html