how to selectively get multiple moving objects rotate?

Question

I am new to corona and I am trying to make multiple objects get moving, and selectively make them rotate one at a time. I should be able to select any one object by tapping on it, and then by clicking a button, it should rotate by X degree (for each click). I have the following code working for one object. But stuck on getting the setup for multiple moving objects. I apologize if it is basic.

local Button = display.newRect(200,200, 10, 40)
local obj = display.newRect(50,50, 10, 40)
local SPEED = 1
local function move(event)

    obj.x = obj.x + math.cos(math.rad(obj.rotation)) * SPEED
    obj.y = obj.y + math.sin(math.rad(obj.rotation)) * SPEED

end

local function rotate(event)
    obj.rotation = obj.rotation + 45
end

Runtime:addEventListener("enterFrame", move)
Button:addEventListener("tap", rotate)

Answer 1

Just update your code to have a "selected" object, like this:

local selectedObject = nil
local Button = display.newRect(200,200, 10, 40)
local obj = display.newRect(50,50, 10, 40)
local SPEED = 1

local function select(event)
    selectedObject = event.target
end

local function move(event)

    obj.x = obj.x + math.cos(math.rad(obj.rotation)) * SPEED
    obj.y = obj.y + math.sin(math.rad(obj.rotation)) * SPEED

end

local function rotate(event)
    if selectedObject then
        selectedObject.rotation = selectedObject.rotation + 45
    end
end

obj:addEventListener("tap", select)
Runtime:addEventListener("enterFrame", move)
Button:addEventListener("tap", rotate)