Basalt/docs/events/mouseEvents.md

Here we will talk about mouse events and how you can manipulate them. There are 2 possible mouse events you can add to almost every visual object.

onClick

onClick(self, button, x, y)
The computercraft event which triggers this method is mouse_click and monitor_touch. Any visual object can register onClick events.

Here is a example on how to add a onClick event to your button:

local basalt = dofile("basalt.lua")

local mainFrame = basalt.createFrame("myMainFrame"):show()
local button = mainFrame:addButton("myButton"):setPosition(3,3):setSize(12,3):setText("Click"):show()

function buttonOnClick()
  basalt.debug("Button got clicked!")
end
button:onClick(buttonOnClick())

onClickUp

onClickUp(self, button, x, y)
The computercraft event which triggers this method is mouse_up. Any visual object can register onClickUp events.

Here is a example on how to add a onClickUp event to your button:

local basalt = dofile("basalt.lua")

local mainFrame = basalt.createFrame("myMainFrame"):show()
local button = mainFrame:addButton("myButton"):setPosition(3,3):setSize(12,3):setText("Click"):show()

function buttonOnClick()
  basalt.debug("Button got clicked!")
end
button:onClick(buttonOnClick)

function buttonOnRelease()
  basalt.debug("Button got released!")
end
button:onClickUp(buttonOnRelease)

onScroll

onScroll(self, direction, x, y)
The computercraft event which triggers this method is mouse_scroll. Any visual object can register a onScroll events.

Here is a example on how to add a onScroll event to your button:

local basalt = dofile("basalt.lua")

local mainFrame = basalt.createFrame("myMainFrame"):show()
local button = mainFrame:addButton("myButton"):setPosition(3,3):setSize(12,3):setText("Click"):show()

function buttonOnScroll()
  basalt.debug("Someone scrolls on me!")
end
button:onScroll(buttonOnScroll)

Beginner Tips

1

Not everyone knows that a function (or in other words a method) does not need to have a name. Instead of a function name you are also able to add the function itself as a argument.

Both do the exact same thing:

local function clickButton()
  basalt.debug("I got clicked!")
end
button:onClick(clickButton)

button:onClick(function()
  basalt.debug("I got clicked!")
end)

2

there is also a function with which you can check if the user is holding a key down, it is called basalt.isKeyDown(). It's especially useful for click events. Let us say you want a button to execute something, but if you are holding ctrl down, something in the execution should get changed. This is how you would achieve that:

button:onClick(function()
  if(basalt.isKeyDown(keys.leftCtrl)then
    basalt.debug("Ctrl is down!")
  else
    basalt.debug("Ctrl is up!")
  end
end)

Make sure to always use the available keys table: https://computercraft.info/wiki/Keys_(API)