#73 waste selection

graphics/elements/controls/multi_button.lua

@@ -0,0 +1,112 @@
+-- Button Graphics Element
+
+local element = require("graphics.element")
+local util    = require("scada-common.util")
+
+---@class button_option
+---@field text string
+---@field fg_bg cpair
+---@field active_fg_bg cpair
+---@field _lpad integer automatically calculated left pad
+---@field _start_x integer starting touch x range (inclusive)
+---@field _end_x integer ending touch x range (inclusive)
+
+---@class multi_button_args
+---@field options table button options
+---@field callback function function to call on touch
+---@field default? boolean default state, defaults to options[1]
+---@field min_width? integer text length + 2 if omitted
+---@field parent graphics_element
+---@field id? string element id
+---@field x? integer 1 if omitted
+---@field y? integer 1 if omitted
+---@field height? integer parent height if omitted
+---@field fg_bg? cpair foreground/background colors
+
+-- new multi button (latch selection, exclusively one button at a time)
+---@param args multi_button_args
+---@return graphics_element element, element_id id
+local function multi_button(args)
+    assert(type(args.options) == "table", "graphics.elements.controls.multi_button: options is a required field")
+    assert(type(args.callback) == "function", "graphics.elements.controls.multi_button: callback is a required field")
+
+    -- single line
+    args.height = 3
+
+    -- button state (convert nil to 1 if missing)
+    local state = args.default or 1
+
+    -- determine widths
+    local max_width = 1
+    for i = 1, #args.options do
+        local opt = args.options[i] ---@type button_option
+        if string.len(opt.text) > max_width then
+            max_width = string.len(opt.text)
+        end
+    end
+
+    local button_width = math.max(max_width, args.min_width or 1)
+
+    args.width = (button_width * #args.options) + #args.options + 1
+
+    -- create new graphics element base object
+    local e = element.new(args)
+
+    -- calculate required button information
+    local next_x = 2
+    for i = 1, #args.options do
+        local opt = args.options[i] ---@type button_option
+        local w = string.len(opt.text)
+
+        opt._lpad = math.floor((e.frame.w - w) / 2)
+        opt._start_x = next_x
+        opt._end_x = next_x + button_width - 1
+
+        next_x = next_x + (button_width + 1)
+    end
+
+    -- show the button state
+    local function draw()
+        for i = 1, #args.options do
+            local opt = args.options[i] ---@type button_option
+
+            e.window.setCursorPos(opt._start_x, 2)
+
+            if state == i then
+                -- show as pressed
+                e.window.setTextColor(opt.active_fg_bg.fgd)
+                e.window.setBackgroundColor(opt.active_fg_bg.bkg)
+            else
+                -- show as unpressed
+                e.window.setTextColor(opt.fg_bg.fgd)
+                e.window.setBackgroundColor(opt.fg_bg.bkg)
+            end
+
+            e.window.write(util.pad(opt.text, button_width))
+        end
+    end
+
+    -- initial draw
+    draw()
+
+    -- handle touch
+    ---@param event monitor_touch monitor touch event
+    function e.handle_touch(event)
+        -- determine what was pressed
+        if event.y == 2 then
+            for i = 1, #args.options do
+                local opt = args.options[i] ---@type button_option
+
+                if event.x >= opt._start_x and event.x <= opt._end_x then
+                    state = i
+                    draw()
+                    args.callback(state)
+                end
+            end
+        end
+    end
+
+    return e.get()
+end
+
+return multi_button