(Help) Gui / guiSetVisible

[Simon54]

Hi, I have about 50 or more gui-images to make visible / invisible but im getting all errors - @'guiSetVisible' expected element at argument 1, got string "button_1_img"
I need to use a loop to concat and change button numbers 1-50. How to actually make this work?

-- button elements
button_1_img = guiCreateStaticImage ( 500, 500, 32, 32, "img/buttons/button_select.png", false, main_window )
button_2_img = guiCreateStaticImage ( 550, 500, 32, 32, "img/buttons/button_select.png", false, main_window )
button_3_img = guiCreateStaticImage ( 600, 500, 32, 32, "img/buttons/button_select.png", false, main_window )
button_4_img = guiCreateStaticImage ( 650, 500, 32, 32, "img/buttons/button_select.png", false, main_window )
button_5_img = guiCreateStaticImage ( 700, 500, 32, 32, "img/buttons/button_select.png", false, main_window )
-- + 45

for index=1,50 do

	guiSetVisible ( "button_"..index.."_img", true )
end

 

[IIYAMA]

1 hour ago, Simon54 said:

How to actually make this work?

Normally you use a table.

But if you aren't able to work with those yet. Here is a very dirty way of doing it:

for index=1,50 do
	guiSetVisible ( _G["button_"..index.."_img"], true )
end

The _G accesses global variables. (variables without the keyword local in front of them)

It is not recommended to use this method more than once. It is purely to demonstrate how to do it your way. But not the way Lua intended it to be used

 

For working with tables, please take a look at:

 

[Tekken]

7 hours ago, IIYAMA said:

But not the way Lua intended it to be used

Hi, may I ask why is this a bad implementation ?

 

Greetings.

[IIYAMA]

3 hours ago, Tekken said:

Hi, may I ask why is this a bad implementation ?

 

I can think of a few, no actual numbers to back this up to be honest.

• The memory access speed. While _G is also a table, the access method is done with a string instead of an integer.
  • There are a lot of items in the _G table, adding a lot of extra items:
    • Will slow down the loopup with the _G table.
    • And might slowdown the lookup time for globals in general. (no proof/numbers here to be honest)
       
  • And on top of that I am not sure if _G (runtime) lookup speed can actually be optimised by the CPU. It is not a regular table after all.
     
• Making collision/override possible, which is very easy to do in this case. Creating bugs in your code without knowing it.

 

[Simon54]

Thanks IIYAMA, the dirty way does what I need it to do and it really saved a ton of lines in the code. I am however using it more than once in the same script, I think as long as it doesn't cause any major performance or security implications it should be okay until I figure out how to go about doing it the table way. Thanks again.

[Tekken]

1 hour ago, Simon54 said:

Thanks IIYAMA, the dirty way does what I need it to do and it really saved a ton of lines in the code. I am however using it more than once in the same script, I think as long as it doesn't cause any major performance or security implications it should be okay until I figure out how to go about doing it the table way. Thanks again.

The "table way" is actually pretty straight forward, here is a simple example:

 

local guiStuff = {}; --create the table.

guiStuff[ #guiStuff + 1 ] = guiCreateStaticImage("IMAGE1", x, y); --#guiStuff > gets the total number of items in the table and we add one so basically we do [0 + 1] then [1 + 1], [2 + 1] and so on..
guiStuff[ #guiStuff + 1 ] = guiCreateStaticImage("IMAGE2", x, y);
guiStuff[ #guiStuff + 1 ] = guiCreateStaticImage("IMAGE3", x, y);
guiStuff[ #guiStuff + 1 ] = guiCreateStaticImage("IMAGE4", x, y);
--so on as many times you want....


for index = 1, #guiStuff do
  guiSetVisible(guiStuff[index], true);
end

--you can also acces any of the above like this
guiSetVisible(guiStuff[3], false);
--if you are sure of the index

--imagine the table like this:
local guiStuff = {
	[1] = guiCreateStaticImage("IMAGE1", x, y),
	[2] = guiCreateStaticImage("IMAGE2", x, y),
	[3] = guiCreateStaticImage("IMAGE3", x, y),
	[4] = guiCreateStaticImage("IMAGE4", x, y),
};

 

 

[Simon54]

1 hour ago, Tekken said:

The "table way" is actually pretty straight forward, here is a simple example:

 

local guiStuff = {}; --create the table.

guiStuff[ #guiStuff + 1 ] = guiCreateStaticImage("IMAGE1", x, y); --#guiStuff > gets the total number of items in the table and we add one so basically we do [0 + 1] then [1 + 1], [2 + 1] and so on..
guiStuff[ #guiStuff + 1 ] = guiCreateStaticImage("IMAGE2", x, y);
guiStuff[ #guiStuff + 1 ] = guiCreateStaticImage("IMAGE3", x, y);
guiStuff[ #guiStuff + 1 ] = guiCreateStaticImage("IMAGE4", x, y);
--so on as many times you want....


for index = 1, #guiStuff do
  guiSetVisible(guiStuff[index], true);
end

--you can also acces any of the above like this
guiSetVisible(guiStuff[3], false);
--if you are sure of the index

--imagine the table like this:
local guiStuff = {
	[1] = guiCreateStaticImage("IMAGE1", x, y),
	[2] = guiCreateStaticImage("IMAGE2", x, y),
	[3] = guiCreateStaticImage("IMAGE3", x, y),
	[4] = guiCreateStaticImage("IMAGE4", x, y),
};

 

 

Okay perfect, this is also a great example, easy to understand. Thanks Tekken I really appreciate the help!