[*] Initial commit.

widget.lua

@@ -0,0 +1,117 @@
+local rectunion = require('lib.gear.rect').union
+
+local Widget = {
+    __call = function(cls, args)
+        return cls.new(args)
+    end
+}
+Widget.__index = Widget
+
+
+local function raise(widget)
+    local parent = widget.parent
+
+    -- A parent of a widget is necessarily a Layout
+    while parent ~= nil do
+        local stack = parent.stack
+
+        -- Move widget at the end of the stack, so it is rendered last.
+        for i,w in ipairs(stack) do
+            if w == widget then
+                table.remove(stack, i)
+                stack[#stack+1] = widget
+                break
+            end
+        end
+
+        -- Focus widget's container, if any
+        widget = parent
+        parent = widget.parent
+    end
+end
+
+function Widget:grabFocus()
+    local ui = self.ui
+    local focused = ui.focused
+
+    if focused == self then
+        return
+    end
+    if focused ~= nil then
+        -- Notify leave
+        focused.hovered = false
+        if focused.grabkeyboard then
+            if love.system.getOS() == 'Android' or love.system.getOS() == 'iOS' then
+                love.keyboard.setTextInput(false)
+            end
+            love.keyboard.setKeyRepeat(false)
+        end
+
+        focused:onLeave()
+    end
+
+    local wasHovered = self.hovered
+
+    self.hovered = true
+    if self.grabkeyboard then
+        love.keyboard.setTextInput(true, self.x,self.y,self.w,self.h)
+        love.keyboard.setKeyRepeat(true)
+    end
+    if not wasHovered then
+        -- First time hovered, notify enter
+        self:onEnter()
+    end
+
+    -- Raise widget
+    ui.focused = self
+    raise(self)
+end
+
+function Widget:isFocused()
+    return self.ui.focused == self
+end
+
+function Widget.recalculateBounds()
+    local widget = self.parent
+    while widget ~= nil do
+        local rx,ry,rw,rh = widget.x,widget.y,-1,-1
+
+        for _,w in ipairs(widget) do
+            rx,ry,rw,rh = rectunion(rx,ry,rw,rh, w.x,w.y,w.w,w.h)
+        end
+
+        widget.x = rx
+        widget.y = ry
+        widget.w = rw
+        widget.h = rh
+
+        widget = widget.parent
+    end
+end
+
+-- Helper for drawing
+function Widget:colorForState()
+    if self.active then
+        return self.color.active
+    elseif self:isFocused() then
+        return self.color.hovered
+    else
+        return self.color.normal
+    end
+end
+
+-- Common NOP event handlers
+function Widget:onHit() end
+function Widget:onEnter() end
+function Widget:onLeave() end
+function Widget:onChange() end
+
+-- NOP input event handlers
+function Widget:onActionInput(action) end
+function Widget:onPointerInput(x,y, clicked) end
+
+-- NOP UI event handlers
+function Widget:update(dt) end
+function Widget:draw() end
+
+return Widget