How to measure the size of the button's label in Corona SDK

Question

I need to make a button with a dynamic width, based on its label.

So, I though in measuring the size of the label of the button but, the problem is that I cannot find nowhere how to do that without creating a display.newText of the label.

How can I do that? Is there any other way to dynamically set the button width based on its label?

Answer 1

Ok, I managed how to do that. Here's the solution:

Button creation

local function createButton(price)
    local button= widget.newButton{
        height = 40,
        label = price.." €",
        labelAlign = "center",
        font = "Arial",
        fontSize = 22,
        labelColor = { default = {0,0,0}, over = {255,255,255} },
        onEvent = function(event)
            if event.phase=="ended" then
                print("done")
            end
        end
    }
    return button
end

Button position and dynamic width

local buy=createButton("10")
buy.width=buy._label.width
buy._label.width=buy.width
buy.x=700-buy.width/2
buy.y=50

local buy_2=createButton("100")
buy_2.width=buy_2._label.width
buy_2._label.width=buy_2.width
buy_2.x=700-buy_2.width/2
buy_2.y=150