allow for lua click handlers

resources/slides.lua

+
+function make_paint(size, color)
+    local paint = Sk.newPaint();
+    paint:setAntiAlias(true)
+    paint:setTextSize(size)
+    paint:setColor(color)
+    return paint
+end
+
+function find_paint(paints, style)
+    if not style then
+        style = "child"
+    end
+    local paint = paints[style]
+    return paint
+end
+
+function draw_node(canvas, node, x, y, paints)
+    if node.text then
+        local paint = find_paint(paints, node.style)
+        canvas:drawText(node.text, x, y, paint)
+    end
+    if node.draw then
+        node.draw(canvas)
+    end
+end
+
+function drawSlide(canvas, slide, template, paints)
+    draw_node(canvas, slide, template.title.x, template.title.y, paints)
+
+    if slide.children then
+        local x = template.child.x
+        local y = template.child.y
+        local dy = template.child.dy
+        for i = 1, #slide.children do
+            draw_node(canvas, slide.children[i], x, y, paints)
+            y = y + dy
+        end
+    end
+end
+
+--------------------------------------------------------------------------------------
+
+gTemplate = {
+    title = { x = 10, y = 64, textSize = 64 },
+    child = { x = 40, y = 120, dy = 50, textSize = 40 },
+}
+
+gPaints = {}
+gPaints.title = make_paint(gTemplate.title.textSize, { a=1, r=0, g=0, b=0 } )
+gPaints.child = make_paint(gTemplate.child.textSize, { a=.75, r=0, g=0, b=0 } )
+
+gRedPaint = Sk.newPaint()
+gRedPaint:setAntiAlias(true)
+gRedPaint:setColor{a=1, r=1, g=0, b=0 }
+
+gSlides = {
+    {   text = "Title1", style="title", color = { a=1, r=1, g=0, b=0 },
+        children = {
+            {   text = "bullet 1", style = "child" },
+            {   text = "bullet 2", style = "child" },
+            {   text = "bullet 3", style = "child" },
+            {   draw = function (canvas)
+                    canvas:drawOval({left=300, top=300, right=400, bottom=400}, gRedPaint)
+            end },
+        },
+    },
+    {   text = "Title2", style="title", color = { a=1, r=0, g=1, b=0 },
+        children = {
+            {   text = "bullet uno", style = "child" },
+            {   text = "bullet 2", style = "child" },
+            {   text = "bullet tres", style = "child" },
+        }
+    },
+    {   text = "Title3", style="title",
+        children = {
+            {   text = "bullet 1", style = "child", },
+            {   text = "bullet 2", style = "child", color = { r=0, g=0, b=1 } },
+            {   text = "bullet 3", style = "child" },
+        }
+    }
+}
+
+gSlideIndex = 1
+
+--------------------------------------------------------------------------------------
+
+function onDrawContent(canvas)
+    drawSlide(canvas, gSlides[gSlideIndex], gTemplate, gPaints)
+
+    return false -- we're not animating
+end
+
+function onClickHandler(x, y)
+    if x < 100 and y < 100 then
+        onNextSlide()
+        return true
+    end
+    return false
+end
+
+function onNextSlide()
+    gSlideIndex = gSlideIndex + 1
+    if gSlideIndex > #gSlides then
+        gSlideIndex = 1
+    end
+end
+