Files
love-luigi/luigi/widget/slider.lua

93 lines
2.6 KiB
Lua

--[[--
A slider.
Dragging this widget changes its `value` property to a
number between 0 and 1, inclusive.
@widget slider
--]]--
return function (self)
local function clamp (value)
return value < 0 and 0 or value > 1 and 1 or value
end
self.value = clamp(self.value or 0)
self.step = self.step or 0.01
local spacer = self:addChild()
local thumb = self:addChild {
type = 'slider.thumb',
}
local function unpress (event)
if event.button ~= 'left' then return end
thumb.pressed.left = nil -- don't make the thumb appear pushed in
return false -- don't press thumb on focused keyboard activation
end
thumb:onPressStart(unpress)
thumb:onPressEnter(unpress)
thumb:onKeyPress(function (event)
local key = event.key
if key == 'left' or key == 'down' then
self.value = clamp(self.value - self.step)
elseif key == 'right' or key == 'up' then
self.value = clamp(self.value + self.step)
end
end)
local function press (event)
if event.button ~= 'left' then return end
local x1, y1, w, h = self:getRectangle(true, true)
local x2, y2 = x1 + w, y1 + h
if self.flow == 'x' then
local halfThumb = thumb:getWidth() / 2
x1, x2 = x1 + halfThumb, x2 - halfThumb
self.value = clamp((event.x - x1) / (x2 - x1))
else
local halfThumb = thumb:getHeight() / 2
y1, y2 = y1 + halfThumb, y2 - halfThumb
self.value = 1 - clamp((event.y - y1) / (y2 - y1))
end
thumb:focus()
end
self:onPressStart(press)
self:onPressDrag(press)
self:onEnter(function (event)
thumb.hovered = true
end)
self:onLeave(function (event)
thumb.hovered = false
end)
self:onChange(function (event)
self:reshape()
end)
self:onReshape(function (event)
local x1, y1, w, h = self:getRectangle(true, true)
local x2, y2 = x1 + w, y1 + h
if self.flow == 'x' then
thumb.width = 0
thumb.height = false
local halfThumb = thumb:getWidth() / 2
x1, x2 = x1 + halfThumb, x2 - halfThumb
spacer.width = self.value * (x2 - x1)
spacer.height = false
else
thumb.width = false
thumb.height = 0
local halfThumb = thumb:getHeight() / 2
y1, y2 = y1 + halfThumb, y2 - halfThumb
spacer.width = false
spacer.height = (1 - self.value) * (y2 - y1)
end
end)
end