added checkbox graphics element

graphics/element.lua

@@ -20,6 +20,7 @@ local element = {}
 
 ---@alias graphics_args graphics_args_generic
 ---|waiting_args
+---|checkbox_args
 ---|hazard_button_args
 ---|multi_button_args
 ---|push_button_args

graphics/elements/controls/checkbox.lua

@@ -0,0 +1,84 @@
+-- Checkbox Graphics Element
+
+local core    = require("graphics.core")
+local element = require("graphics.element")
+
+---@class checkbox_args
+---@field label string checkbox text
+---@field box_fg_bg cpair colors for checkbox
+---@field callback function function to call on press
+---@field parent graphics_element
+---@field id? string element id
+---@field x? integer 1 if omitted
+---@field y? integer 1 if omitted
+---@field fg_bg? cpair foreground/background colors
+---@field hidden? boolean true to hide on initial draw
+
+-- new checkbox control
+---@param args checkbox_args
+---@return graphics_element element, element_id id
+local function checkbox(args)
+    assert(type(args.label) == "string", "graphics.elements.controls.checkbox: label is a required field")
+    assert(type(args.box_fg_bg) == "table", "graphics.elements.controls.checkbox: box_fg_bg is a required field")
+    assert(type(args.callback) == "function", "graphics.elements.controls.checkbox: callback is a required field")
+
+    args.height = 1
+    args.width = 3 + string.len(args.label)
+
+    -- create new graphics element base object
+    local e = element.new(args)
+
+    e.value = false
+
+    -- show the button state
+    local function draw()
+        e.window.setCursorPos(1, 1)
+
+        if e.value then
+            -- show as selected
+            e.window.setTextColor(args.box_fg_bg.bkg)
+            e.window.setBackgroundColor(args.box_fg_bg.fgd)
+            e.window.write("\x88")
+            e.window.setTextColor(args.box_fg_bg.fgd)
+            e.window.setBackgroundColor(e.fg_bg.bkg)
+            e.window.write("\x95")
+        else
+            -- show as unselected
+            e.window.setBackgroundColor(args.box_fg_bg.bkg)
+            e.window.write("\x80")
+            e.window.setTextColor(args.box_fg_bg.bkg)
+            e.window.setBackgroundColor(e.fg_bg.bkg)
+            e.window.write("\x95")
+        end
+    end
+
+    -- handle mouse interaction
+    ---@param event mouse_interaction mouse event
+    function e.handle_mouse(event)
+        if e.enabled and core.events.was_clicked(event.type) then
+            e.value = not e.value
+            draw()
+            args.callback(e.value)
+        end
+    end
+
+    -- set the value
+    ---@param val integer new value
+    function e.set_value(val)
+        e.value = val
+        draw()
+    end
+
+    -- write label text
+    e.window.setCursorPos(3, 1)
+    e.window.setTextColor(e.fg_bg.fgd)
+    e.window.setBackgroundColor(e.fg_bg.bkg)
+    e.window.write(args.label)
+
+    -- initial draw
+    draw()
+
+    return e.complete()
+end
+
+return checkbox