devel/dflayout: rework fort toolbar demos

Have the toolbar demos set their own frames via computeFrame.

These overridden computeFrames also allow the button extent indicator
strings to draw over the edges of the Panel's border. The left, right,
and secondary toolbars don't have their own "borders" like the center
toolbar, so the first and last buttons in those toolbars previously had
their button indicators cut off by the Panel border.

Certainly not a good look for general use, but for a devel inspection
tool, it should be okay (and leaves the Panel borders showing the true
extent of each toolbar).

Only compute the button strings once for the static left, center, and
right toolbars.

Author: ChrisJohnsen

devel/dflayout.lua

@@ -132,35 +132,140 @@ local function fort_toolbars_visible()
     return visible() and fort_toolbars_demo.active
 end
 
-FortToolbarDemoPanel = defclass(FortToolbarDemoPanel, widgets.Panel)
-FortToolbarDemoPanel.ATTRS{
+local secondary_visible = false
+
+local function primary_toolbar_dy()
+    if secondary_visible then
+        -- When a secondary toolbar is active, move the primary demos up to let
+        -- the secondary demo be right above the actual secondary:
+        -- {l demo}   {c demo}   {r demo}
+        --               {s demo}
+        --               [s tool]
+        -- [l tool]   [c tool]   [r tool]  (bottom of UI)
+        return -(layout.TOOLBAR_HEIGHT + 2 * layout.SECONDARY_TOOLBAR_HEIGHT)
+    else
+        -- Otherwise, draw primary toolbar demos right above the primary
+        -- toolbars:
+        -- {l demo}   {c demo}   {r demo}
+        -- [l tool]   [c tool]   [r tool]  (bottom of UI)
+        return -layout.TOOLBAR_HEIGHT
+    end
+end
+
+-- Generates a `view:computeFrame()` function that tracks the placement of the
+-- given `toolbar`.
+--
+-- Note: The returned function does not return a separate body rect; subviews
+-- will be able to overwrite the normal UI-drawn frame!
+---@param toolbar DFLayout.Toolbar
+---@param dy_fn fun(): integer
+---@return function
+local function get_computeFrame_fn(toolbar, dy_fn)
+    return function(self, parent_rect)
+        local ir = gui.get_interface_rect()
+        local frame = toolbar.frame(ir)
+        return gui.mkdims_wh(
+            ir.x1 + frame.l,
+            ir.y1 + frame.t + dy_fn(),
+            frame.w,
+            frame.h)
+    end
+end
+
+---@param buttons DFLayout.Toolbar.NamedButtons
+local function buttons_string(buttons)
+    local sorted = {}
+    for _, button in pairs(buttons) do
+        utils.insert_sorted(sorted, button, 'offset')
+    end
+    -- For a one-column button, use | to indicate the button's position.
+    -- For wider buttons, use shapes like /\ or /--\ to illustrate the
+    -- button's position and width.
+    local str = ''
+    for i, o in ipairs(sorted) do
+        if o.offset > #str then
+            str = str .. (' '):rep(o.offset - #str)
+        end
+        if o.width == 1 then
+            str = str .. '|'
+        elseif o.width > 1 then
+            str = str .. '/' .. ('-'):rep(o.width - 2) .. '\\'
+        end
+    end
+    return str
+end
+
+---@class ToolbarDemo.attrs: widgets.Panel.attrs
+---@class ToolbarDemo.attrs.partial: widgets.Panel.attrs.partial
+---@class ToolbarDemo.initTable: ToolbarDemo.attrs.partial, { toolbar?: DFLayout.Toolbar, toolbar_dy?: fun(): integer }
+---@class ToolbarDemo: widgets.Panel
+---@field super widgets.Panel
+---@field ATTRS ToolbarDemo.attrs|fun(attributes: ToolbarDemo.attrs.partial)
+---@overload fun(init_table: ToolbarDemo.initTable): self
+ToolbarDemo = defclass(ToolbarDemo, widgets.Panel)
+ToolbarDemo.ATTRS{
     frame_style = function(...)
         local style = gui.FRAME_THIN(...)
         style.signature_pen = false
         return style
     end,
-    visible_override = true,
     visible = fort_toolbars_visible,
     frame_background = { ch = 32, bg = COLOR_BLACK },
 }
 
-local left_toolbar_demo = FortToolbarDemoPanel{
+---@param args ToolbarDemo.initTable
+function ToolbarDemo:init(args)
+    self.label = widgets.Label{ frame = { l = 0 } }
+    if args.toolbar and args.toolbar_dy then
+        self:update_to_toolbar(args.toolbar, args.toolbar_dy)
+    end
+    self:addviews{ self.label }
+end
+
+---@param toolbar DFLayout.Toolbar
+---@param dy fun(): integer
+---@return unknown
+function ToolbarDemo:update_to_toolbar(toolbar, dy)
+    -- set button representation string
+    local text = buttons_string(toolbar.buttons)
+    local l_inset = 0
+    if text:sub(1, 1) == ' ' then
+        -- don't overwrite the left border edge with a plain space
+        l_inset = 1
+        text = text:sub(2)
+    end
+    self.label.frame.l = l_inset
+    self.label:setText(text)
+
+    -- track actual toolbar, but with a y offset
+    self.computeFrame = get_computeFrame_fn(toolbar, dy)
+
+    return self
+end
+
+local left_toolbar_demo = ToolbarDemo{
     frame_title = 'left toolbar',
-    subviews = { widgets.Label{ view_id = 'buttons', frame = { l = 0, r = 0 } } },
+    toolbar = layout.fort.toolbars.left,
+    toolbar_dy = primary_toolbar_dy,
 }
-local center_toolbar_demo = FortToolbarDemoPanel{
+
+local center_toolbar_demo = ToolbarDemo{
     frame_title = 'center toolbar',
-    subviews = { widgets.Label{ view_id = 'buttons', frame = { l = 0, r = 0 } } },
+    toolbar = layout.fort.toolbars.center,
+    toolbar_dy = primary_toolbar_dy,
 }
-local right_toolbar_demo = FortToolbarDemoPanel{
+
+local right_toolbar_demo = ToolbarDemo{
     frame_title = 'right toolbar',
-    subviews = { widgets.Label{ view_id = 'buttons', frame = { l = 0, r = 0 } } },
+    toolbar = layout.fort.toolbars.right,
+    toolbar_dy = primary_toolbar_dy,
 }
-local secondary_visible = false
-local secondary_toolbar_demo = FortToolbarDemoPanel{
+
+local secondary_toolbar_demo = ToolbarDemo{
     frame_title = 'secondary toolbar',
-    subviews = { widgets.Label{ view_id = 'buttons', frame = { l = 0, r = 0 } } },
-    visible = function() return fort_toolbars_visible() and secondary_visible end,
+    visible = function()
+        return fort_toolbars_visible() and secondary_visible
+    end,
 }
 
 fort_toolbars_demo.views = {
@@ -172,59 +277,26 @@ fort_toolbars_demo.views = {
 
 ---@param secondary? DFLayout.Fort.SecondaryToolbar.Names
 local function update_fort_toolbars(secondary)
-    -- by default, draw primary toolbar demonstrations right above the primary toolbars:
-    -- {l demo}   {c demo}   {r demo}
-    -- [l tool]   [c tool]   [r tool]  (bottom of UI)
-    local toolbar_demo_dy = -layout.TOOLBAR_HEIGHT
-    local ir = gui.get_interface_rect()
-    ---@param v widgets.Panel
-    ---@param frame widgets.Widget.frame
-    ---@param buttons DFLayout.Toolbar.NamedButtons
-    local function update(v, frame, buttons)
-        v.frame = {
-            w = frame.w,
-            h = frame.h,
-            l = frame.l + ir.x1,
-            t = frame.t + ir.y1 + toolbar_demo_dy,
-        }
-        local sorted = {}
-        for _, button in pairs(buttons) do
-            utils.insert_sorted(sorted, button, 'offset')
-        end
-        local buttons = ''
-        for i, o in ipairs(sorted) do
-            if o.offset > #buttons then
-                buttons = buttons .. (' '):rep(o.offset - #buttons)
-            end
-            if o.width == 1 then
-                buttons = buttons .. '|'
-            elseif o.width > 1 then
-                buttons = buttons .. '/' .. ('-'):rep(o.width - 2) .. '\\'
-            end
+    local function updateLayout(view)
+        if view.frame_parent_rect then
+            view:updateLayout()
         end
-        v.subviews.buttons:setText(
-            buttons:sub(2) -- the demo panel border is at offset 0, so trim first character to start at offset 1
-        )
-        v:updateLayout()
     end
     if secondary then
-        -- a secondary toolbar is active, move the primary demonstration up to
-        -- let the secondary be demonstrated right above the actual secondary:
-        -- {l demo}   {c demo}   {r demo}
-        --               {s demo}
-        --               [s tool]
-        -- [l tool]   [c tool]   [r tool]  (bottom of UI)
-        update(secondary_toolbar_demo, layout.fort.secondary_toolbars[secondary].frame(ir),
-            layout.fort.secondary_toolbars[secondary].buttons)
+        -- show secondary demo just above actual secondary
+        local function dy()
+            return -layout.SECONDARY_TOOLBAR_HEIGHT
+        end
+        secondary_toolbar_demo:update_to_toolbar(layout.fort.secondary_toolbars[secondary], dy)
+        updateLayout(secondary_toolbar_demo)
         secondary_visible = true
-        toolbar_demo_dy = toolbar_demo_dy - 2 * layout.SECONDARY_TOOLBAR_HEIGHT
     else
         secondary_visible = false
     end
 
-    update(left_toolbar_demo, layout.fort.toolbars.left.frame(ir), layout.fort.toolbars.left.buttons)
-    update(right_toolbar_demo, layout.fort.toolbars.right.frame(ir), layout.fort.toolbars.right.buttons)
-    update(center_toolbar_demo, layout.fort.toolbars.center.frame(ir), layout.fort.toolbars.center.buttons)
+    updateLayout(left_toolbar_demo)
+    updateLayout(right_toolbar_demo)
+    updateLayout(center_toolbar_demo)
 end
 
 local tool_from_designation = {
@@ -303,13 +375,14 @@ fort_toolbars_demo.update = function()
 end
 
 local secondary
+local center_render = center_toolbar_demo.render
 function center_toolbar_demo:render(...)
     local new_secondary = active_secondary()
     if new_secondary ~= secondary then
         secondary = new_secondary
         update_fort_toolbars(secondary)
     end
-    return FortToolbarDemoPanel.render(self, ...)
+    return center_render(self, ...)
 end
 
 --- start demo control window ---