Canvas:onShow() | LuaRT free and open source Windows programming framework for Lua

Canvas:onShow() event

This event is fired when the Canvas is shown (with a call to Canvas:show() or setting the Canvas.visible property to true).

Return value

The event returns no value.

Example


local ui = require "ui"
require "canvas"

-- create a simple Window
local win = ui.Window("Canvas:onShow() sample", 640, 480)

-- create a canvas and center it
local canvas = ui.Canvas(win, 0, 0, 600, 400)
canvas.align = "all"
canvas.visible = false

-- set the onShow() event handler to draw on the canvas
function canvas:onShow()
    self:begin()
    -- clears the canvas backbuffer with white color
    self:clear(0xFFFFFFFF)
    -- prints text
    self:print("Canvas is now visible !", 10, 10)
    -- shows the backbuffer
    self:flip()
end

-- Launch a Task to show the Canvas in 2sec
async(function()
    sleep(2000)
    canvas:show()
end)

ui.run(win):wait()