How can I get the colour (fill) of a DisplayObject in response to an event like a touch in Corona SDK?

coronasdk

Solution

Create your rectangle:

local rectangle = display.newRect(0, 0, 100, 100)

Put your color in RGBA (you can leave out the A) format in a table, and store it as a "custom property" for the rectangle:

rectangle.fillColor = {110, 30, 25}

Through the magic of the unpack function, which returns the values of a table, pass the table to setFillColor:

rectangle:setFillColor( unpack(rectangle.fillColor) )

Now you can always get the color like so:

print( unpack(rectangle.fillColor) ) --> 110    30    25

or

print( rectangle.fillColor ) -- simply returns the table

or to put each color in a variable:

local red, green, blue, alpha = unpack(rectangle.fillColor)

You'll see how this can come in handy for other things as well.

EDIT

Just thought of another cool way of doing it, by highjacking the setFillColor function:

local function decorateRectangle(rect)
    rect.cachedSetFillColor = rect.setFillColor -- store setFillColor function

    function rect:setFillColor(...) -- replace it with our own function
        self:cachedSetFillColor(...)
        self.storedColor = {...} -- store color
    end

    function rect:getFillColor()
        return unpack(self.storedColor)
    end
end

local rectangle = display.newRect(0, 0, 100, 100)

decorateRectangle(rectangle) -- "decorates" rectangle with more awesomeness

Now you can use setFillColor to set color as normal, AND getFillColor to return it :)

rectangle:setFillColor(100, 30, 255, 255)

print(rectangle:getFillColor())

Problem

Original source