add calc example && update readme

README.md

@@ -1,3 +1,7 @@
 # Syscalls
 
 Syscalls library for Lua
+
+## Examples
+
+you can find it in tests folder

tests/calc.lua

@@ -0,0 +1,145 @@
+local syscalls = require("syscalls")
+
+local systemColors = syscalls.GetSystemColors()
+local skinHeight = syscalls.GetSkinHeight()
+
+local display = "0"
+local ans = "0"
+
+local buttons = {
+	{"1", "2", "3", "+", "-"},
+	{"4", "5", "6", "*", "/"},
+	{"7", "8", "9", "%", ""},
+	{"0", ".", "Ans", "="}
+}
+
+local function DrawDisplay()
+	syscalls.DrawText(
+    	display,
+    	20,
+    	20 + skinHeight,
+    	systemColors.workText
+    )
+end
+
+local function redraw()
+    syscalls.StartRedraw()
+
+    syscalls.CreateWindow(
+    	100,
+    	100,
+    	200,
+    	256,
+    	"lua example Calc",
+    	systemColors.workArea,
+    	syscalls.windowStyle.WithSkinFixSizes
+    )
+
+    DrawDisplay()
+
+    --local t = syscalls.ThreadInfo()
+
+    local i = 2
+    local h = math.floor(150 / #buttons)
+
+    for rowN, row in pairs(buttons) do
+
+    	local w = math.floor(200 / #row)
+
+       	for col, v in pairs(row) do
+
+    		local x = math.floor((col-1) * w)
+    		local y = math.floor((rowN-1) * h + 50 + skinHeight)
+
+    		syscalls.DefineButton(
+    			x,
+    			y,
+    			w,
+    			h,
+    			i,
+    			systemColors.workButton
+    		)
+
+    		syscalls.DrawText(
+    			v,
+    			x,
+    			y,
+    			systemColors.workButtonText
+    		)
+
+    		i=i+1
+    	end
+    end
+
+
+    syscalls.EndRedraw()
+end
+
+local function CheckButton(ButtonID)
+	local i = 2
+	for k, v in pairs(buttons) do
+		for j, s in pairs(v) do
+			if ButtonID ~= i then
+				i = i + 1
+			else
+    			return s
+			end
+		end
+	end
+
+	return nil
+end
+
+local function checkInput(s)
+	if s == "=" then
+		display = assert(load( "return " .. display))()
+		ans = display
+	elseif s == "Ans" then
+       	display = display .. ans
+    elseif s then
+      	if display == "0" then
+       		display = s
+       	else
+       		display = display .. s
+       	end
+	end
+
+	syscalls.DrawRectangle(20, 20 + skinHeight, 200, 30, systemColors.workArea)
+	DrawDisplay()
+end
+
+-- main
+
+redraw()
+ 
+local exit = false
+while not exit do
+    local event = syscalls.WaitEvent()
+
+    if event == syscalls.Event.Redraw then
+        redraw()
+    elseif event == syscalls.Event.Button then
+        local ButtonID = syscalls.GetButton()
+
+        if ButtonID == syscalls.buttons.close then
+            exit = true
+        else
+        	local s = CheckButton(ButtonID)
+
+			checkInput(s)
+        end
+    elseif event == syscalls.Event.Key then
+    	local key, a = syscalls.GetKey()
+
+    	key = key:sub(1, 1)
+
+    	for _, row in pairs(buttons) do
+    		for _, v in pairs(row) do
+    			if v == key then
+    				checkInput(key)
+					break
+    			end
+    		end
+    	end
+    end
+end