Update ci-workflow.yml

Fixes #

.github/workflows/ci-workflow.yml

@@ -7,13 +7,13 @@ jobs:
         name: Build and run
         runs-on: ubuntu-latest
         steps:
-          - uses: actions/checkout@v1
+          - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11
-          - uses: actions/setup-java@v1
+          - uses: actions/setup-java@99b8673ff64fbf99d8d325f52d9a5bdedb8483e9
             with:
-                java-version: '17'
+                java-version: '21.0.5+11.0.LTS'
+                distribution: 'temurin'
           - name: Run.sh
             env:
                 DEFOLD_USER: bjorn.ritzl@gmail.com
                 DEFOLD_AUTH: foobar
-                DEFOLD_BOOSTRAP_COLLECTION: /test/test.collectionc
             run: ./.test/run.sh

.gitignore

@@ -9,3 +9,6 @@ build
 builtins
 .internal
 luacov.report.out
+/.editor_settings
+manifest.private.der
+manifest.public.der

.test/run.sh

@@ -5,7 +5,6 @@ else
 	PLATFORM="$1"
 fi
 
-
 echo "${PLATFORM}"
 
 # {"version": "1.2.89", "sha1": "5ca3dd134cc960c35ecefe12f6dc81a48f212d40"}
@@ -16,26 +15,28 @@ echo "Using Defold dmengine_headless version ${SHA1}"
 # Create dmengine_headless and bob.jar URLs
 DMENGINE_URL="http://d.defold.com/archive/${SHA1}/engine/${PLATFORM}/dmengine_headless"
 BOB_URL="http://d.defold.com/archive/${SHA1}/bob/bob.jar"
+DMENGINE_FILE=dmengine_headless_${SHA1}
+BOB_FILE=bob_${SHA1}.jar
 
 # Download dmengine_headless
-echo "Downloading ${DMENGINE_URL}"
+if ! [ -f ${DMENGINE_FILE} ]; then
-curl -L -o dmengine_headless ${DMENGINE_URL}
+	echo "Downloading ${DMENGINE_URL} to ${DMENGINE_FILE}"
-chmod +x dmengine_headless
+	curl -L -o ${DMENGINE_FILE} ${DMENGINE_URL}
+	chmod +x ${DMENGINE_FILE}
+fi
 
 # Download bob.jar
-echo "Downloading ${BOB_URL}"
+if ! [ -f ${BOB_FILE} ]; then
-curl -L -o bob.jar ${BOB_URL}
+	echo "Downloading ${BOB_URL} to ${BOB_FILE}"
+	curl -L -o ${BOB_FILE} ${BOB_URL}
+fi
 
 # Fetch libraries
-echo "Running bob.jar - resolving dependencies"
+echo "Running ${BOB_FILE} - resolving dependencies"
-java -jar bob.jar --auth "foobar" --email "john@doe.com" resolve
+java -jar ${BOB_FILE} --auth "foobar" --email "john@doe.com" resolve
 
-echo "Running bob.jar - building"
+echo "Running ${BOB_FILE} - building"
-java -jar bob.jar --debug build --keep-unused
+java -jar ${BOB_FILE} --debug build --settings=test.settings
 
-echo "Starting dmengine_headless"
+echo "Starting ${DMENGINE_FILE}"
-if [ -n "${DEFOLD_BOOSTRAP_COLLECTION}" ]; then
+./${DMENGINE_FILE}
-	./dmengine_headless --config=bootstrap.main_collection=${DEFOLD_BOOSTRAP_COLLECTION}
-else
-	./dmengine_headless
-fi

README_API.md

@@ -40,13 +40,18 @@ Clear the stack of screens completely. Any visible screen will be hidden by navi
 * `callback` (function) - Optional function to call when the stack has been cleared.
 
 
-## monarch.back([data], [callback])
+## monarch.back([options], [data], [callback])
 Go back to a previous Monarch screen. This operation will be added to the queue if Monarch is busy.
 
 **PARAMETERS**
+* `options` (table) - Options when showing the new screen (see below).
 * `data` (table) - Optional data to associate with the screen you are going back to.  Retrieve using `monarch.data()`.
 * `callback` (function) - Optional function to call when the previous screen is visible.
 
+The options table can contain the following fields:
+
+* `sequential` (boolean) - If the `sequential` flag is set Monarch will start loading the screen only after the previous screen finished transitioning out.
+
 
 ## monarch.preload(screen_id, [options], [callback])
 Preload a Monarch screen. This will load but not enable the screen. This is useful for content heavy screens that you wish to be able to show without having to wait for it load. This operation will be added to the queue if Monarch is busy.
@@ -177,7 +182,7 @@ Remove a previously added listener.
 
 
 ## monarch.post(screen_id, message_id, [message])
-Post a message to a visible screen. If the screen is created through a collection proxy it must have specified a receiver url. If the screen is created through a collection factory the function will post the message to all game objects within the collection.
+Post a message to a visible screen. The screen must have set a message listener using `monarch.on_post()`.
 
 **PARAMETERS**
 * `screen_id` (string|hash) - Id of the screen to post message to
@@ -207,12 +212,21 @@ IMPORTANT! You must call `monarch.on_message(message_id, message, sender)` from
 * `fn` (function) - The function to call screen focus changes
 
 
-## monarch.on_post(screen_id, fn)
+## monarch.on_post(screen_id, fn_or_url)
-Set a function to be called when `msg.post()` is called on a specific screen. IMPORTANT! You must call `monarch.on_message(message_id, message, sender)` from the same script as this function was called.
+Set either a function to be called when `msg.post()` is called on a specific screen or a URL where the message is sent.
+
+IMPORTANT! If you provide a function you must also make sure to call `monarch.on_message(message_id, message, sender)` from the same script as this function was called.
 
 **PARAMETERS**
 * `screen_id` (string|hash) - Id of the screen
-* `fn` (function) - The function to call when the screen receives a message using `msg.post`
+* `fn_or_url` (function) - The function to call or URL to send message to
+
+
+## monarch.has_missing_resources(screen_id)
+Check if a screen has any missing resources. If the screen is loaded by a collection proxy with Load Dynamically this will use `collectionproxy.missing_resources()`. For other cases this function will always return false.
+
+**RETURN**
+* `result` (boolean) - true if the screen has missing resources
 
 
 ## monarch.debug()

README_TRANSITIONS.md

@@ -114,7 +114,7 @@ end
 
 function on_message(self, message_id, message, sender)
 	if message_id == hash("my_resize_message") then
-		self.transition.window_resized(message.width, message.height)
+		transition.window_resized(message.width, message.height)
 	end
 end
 ```

example/advanced/confirm.gui_script

@@ -29,7 +29,7 @@ function on_input(self, action_id, action)
 			end
 		elseif gui.pick_node(self.no, action.x, action.y) then
 			print("no")
-			monarch.back(function()
+			monarch.back(nil, nil, function()
 				print("back from popup done")
 			end)
 		end

example/advanced/popup.gui_script

@@ -27,7 +27,7 @@ function on_input(self, action_id, action)
 			end)
 		elseif gui.pick_node(self.cancel, action.x, action.y) then
 			print("cancel")
-			monarch.back(function()
+			monarch.back(nil, nil, function()
 				print("back from popup done")
 			end)
 		elseif gui.pick_node(self.about, action.x, action.y) then

example/advanced/pregame.gui_script

@@ -19,7 +19,7 @@ function on_input(self, action_id, action)
 			end)
 		elseif gui.pick_node(self.back, action.x, action.y) then
 			print("back")
-			monarch.back(function()
+			monarch.back(nil, nil, function()
 				print("back from pregame done")
 			end)
 		end

example/slidingwindow/slidingwindow.script

@@ -4,10 +4,25 @@ function init(self)
 	monarch.debug()
 	msg.post("@render:/", "clear_color", { color = vmath.vector4(0.4, 0.6, 0.8,1.0) })
 	msg.post("#", "init_monarch") -- wait until init() has been called for all screen.script instances
+	monarch.add_listener()
+end
+
+function final(self)
+	monarch.remove_listener()
 end
 
 function on_message(self, message_id, message, sender)
 	if message_id == hash("init_monarch") then
 		monarch.show(hash("window1"))
+	elseif message_id == monarch.SCREEN_TRANSITION_IN_STARTED then
+		print("Monarch screen transition in started", message.screen)
+	elseif message_id == monarch.SCREEN_TRANSITION_IN_FINISHED then
+		print("Monarch screen transition in finished", message.screen)
+	elseif message_id == monarch.SCREEN_TRANSITION_OUT_STARTED then
+		print("Monarch screen transition out started", message.screen)
+	elseif message_id == monarch.SCREEN_TRANSITION_OUT_FINISHED then
+		print("Monarch screen transition out finished", message.screen)
+	elseif message_id == monarch.SCREEN_TRANSITION_FAILED then
+		print("Monarch screen transition failed")
 	end
 end

monarch/editor-script/make_monarch.editor_script

@@ -79,16 +79,9 @@ end
 
 gui_template = function(gui_script)
     return [[script: "]].. gui_script .. [["
-background_color {
+    material: "/builtins/materials/gui.material"
-    x: 0.0
+    adjust_reference: ADJUST_REFERENCE_PARENT
-    y: 0.0
+    ]] 
-    z: 0.0
-    w: 0.0
-}
-material: "/builtins/materials/gui.material"
-adjust_reference: ADJUST_REFERENCE_PARENT
-max_nodes: 512
-]] 
 end
 
 gui_script_content = [[local monarch = require "monarch.monarch"
@@ -116,8 +109,8 @@ end
 
 collection_template = function(gui_script, name)
     return [[name: "]].. name .. [["
-scale_along_z: 0
+    scale_along_z: 0
-embedded_instances {
+    embedded_instances {
         id: "go"
         data: "components {\n"
         "  id: \"monarch\"\n"
@@ -151,8 +144,8 @@ embedded_instances {
             y: 1.0
             z: 1.0
         }
-}
+    }
-]]
+    ]]
 
 end
 

monarch/monarch.lua

@@ -21,7 +21,7 @@ local MSG_ENABLE = hash("enable")
 local MSG_DISABLE = hash("disable")
 
 
-local DEPRECATED = hash("/__DEPRECATED__")
+local DEPRECATED = hash("__DEPRECATED__")
 
 -- transition messages
 M.TRANSITION = {}
@@ -228,6 +228,17 @@ function M.is_visible(id)
 end
 
 
+--- Check if a screen is loaded
+-- @param id (string|hash)
+-- @return true if the screen is loaded
+function M.is_loaded(id)
+	assert(id, "You must provide a screen id")
+	id = tohash(id)
+	assert(screens[id], ("There is no screen registered with id %s"):format(tostring(id)))
+	return screens[id].loaded
+end
+
+
 --- Check if a screen is a popup
 -- @param id Screen id
 -- @return true if the screen is a popup
@@ -281,13 +292,13 @@ function M.register_proxy(id, proxy, settings)
 	screen.focus_url = settings and settings.focus_url
 	screen.receiver_url = settings and settings.receiver_url
 	screen.auto_preload = settings and settings.auto_preload
-	if screen.transition_url.path == DEPRECATED then
+	if screen.transition_url.fragment == DEPRECATED then
 		screen.transition_url = nil
 	end
-	if screen.focus_url.path == DEPRECATED then
+	if screen.focus_url.fragment == DEPRECATED then
 		screen.focus_url = nil
 	end
-	if screen.receiver_url.path == DEPRECATED then
+	if screen.receiver_url.fragment == DEPRECATED then
 		screen.receiver_url = nil
 	end
 	if screen.auto_preload then
@@ -419,8 +430,10 @@ local function unload(screen, force)
 	elseif screen.factory then
 		log("unload() factory", screen.id)
 		for id, instance in pairs(screen.factory_ids) do
+			if go.exists(instance) then
 				go.delete(instance)
 			end
+		end
 		screen.factory_ids = nil
 		if screen.auto_preload and not force then
 			screen.loaded = false
@@ -451,8 +464,7 @@ local function preload(screen)
 	screen.preloading = true
 	if screen.proxy then
 		log("preload() proxy")
-		local missing_resources = collectionproxy.missing_resources(screen.proxy)
+		if M.has_missing_resources(screen.id) then
-		if #missing_resources > 0 then
 			local error_message = ("preload() collection proxy %s is missing resources"):format(tostring(screen.id))
 			log(error_message)
 			screen.preloading = false
@@ -509,9 +521,13 @@ local function load(screen)
 		msg.post(screen.proxy, MSG_ENABLE)
 	elseif screen.factory then
 		screen.factory_ids = collectionfactory.create(screen.factory)
+		if screen.transition_id then
 			screen.transition_url = screen.factory_ids[screen.transition_id]
+		end
+		if screen.focus_id then
 			screen.focus_url = screen.factory_ids[screen.focus_id]
 		end
+	end
 	screen.loaded = true
 	screen.preloaded = false
 	return true
@@ -715,8 +731,8 @@ local function back_out(screen, next_screen, wait_for_transition, cb)
 	log("back_out()", screen.id)
 	assert(wait_for_transition ~= nil)
 	run_coroutine(screen, cb, function()
-		notify_transition_listeners(M.SCREEN_TRANSITION_OUT_STARTED, { screen = screen.id, next_screen = next_screen and next_screen.id })
 		active_transition_count = active_transition_count + 1
+		notify_transition_listeners(M.SCREEN_TRANSITION_OUT_STARTED, { screen = screen.id, next_screen = next_screen and next_screen.id })
 		change_context(screen)
 		release_input(screen, next_screen)
 		focus_lost(screen, next_screen)
@@ -863,13 +879,10 @@ function M.show(id, options, data, cb)
 				show_in(screen, top, options and options.reload, add_to_stack, WAIT_FOR_TRANSITION, callbacks.track())
 			else
 				-- show screen
-				local cb = callbacks.track()
+				show_in(screen, top, options and options.reload, add_to_stack, WAIT_FOR_TRANSITION, callbacks.track())
-				show_in(screen, top, options and options.reload, add_to_stack, DO_NOT_WAIT_FOR_TRANSITION, function()
 				if add_to_stack and top and not top.popup then
 					show_out(top, screen, WAIT_FOR_TRANSITION, callbacks.track())
 				end
-					cb()
-				end)
 			end
 
 			callbacks.when_done(function()
@@ -912,7 +925,7 @@ function M.hide(id, cb)
 			log("hide() you can only hide the screen at the top of the stack", id)
 			return false
 		end
-		return M.back(id, cb)
+		return M.back(nil, nil, cb)
 	else
 		log("hide() queuing action", id)
 		queue_action(function(action_done, action_error)
@@ -965,21 +978,27 @@ end
 
 
 -- Go back to the previous screen in the stack.
+-- @param options (table) - Table with options when backing out from the screen (can be nil).
+--		Valid values:
+-- 		* sequential - Set to true to wait for the current screen to hide itself out before starting the
+--				   back in transition even when transitioning to a different scene ID.
+
 -- @param data (*) - Optional data to set for the previous screen
 -- @param cb (function) - Optional callback to invoke when the previous screen is visible again
-function M.back(data, cb)
+function M.back(options, data, cb)
 	log("back() queuing action")
 
 	queue_action(function(action_done)
 		local callbacks = callback_tracker()
-		local back_cb = callbacks.track()
 		local screen = table.remove(stack)
 		if screen then
 			log("back()", screen.id)
 			local top = stack[#stack]
 			-- if we go back to the same screen we need to first hide it
 			-- and wait until it is hidden before we show it again
-			if top and screen.id == top.id then
+			local same_screen = top and top.id == screen.id
+			if same_screen or (options and options.sequential) then
+				local back_cb = callbacks.track()
 				back_out(screen, top, WAIT_FOR_TRANSITION, function()
 					if data then
 						top.data = data
@@ -997,16 +1016,16 @@ function M.back(data, cb)
 					-- we do this to ensure that we do not reset the times step of the screen
 					-- we go back to until it is no longer obscured by the popup
 					if screen.popup and not top.popup then
+						local back_cb = callbacks.track()
 						back_out(screen, top, WAIT_FOR_TRANSITION, function()
 							back_in(top, screen, WAIT_FOR_TRANSITION, back_cb)
 						end)
 					else
-						back_in(top, screen, DO_NOT_WAIT_FOR_TRANSITION, function()
+						back_in(top, screen, WAIT_FOR_TRANSITION, callbacks.track())
-							back_out(screen, top, WAIT_FOR_TRANSITION, back_cb)
+						back_out(screen, top, WAIT_FOR_TRANSITION, callbacks.track())
-						end)
 					end
 				else
-					back_out(screen, top, WAIT_FOR_TRANSITION, back_cb)
+					back_out(screen, top, WAIT_FOR_TRANSITION, callbacks.track())
 				end
 			end
 		end
@@ -1113,6 +1132,20 @@ function M.preload(id, options, cb)
 	return true -- return true for legacy reasons (before queue existed)
 end
 
+--- Check if a screen has missing resources, always returns false for factory
+-- @param id (string|hash) - Id of the screen to preload
+function M.has_missing_resources(id)
+	assert(id, "You must provide a screen id")
+	id = tohash(id)
+	assert(screens[id], ("There is no screen registered with id %s"):format(tostring(id)))
+
+	local screen = screens[id]
+	if screen.proxy then
+		local missing_resources = collectionproxy.missing_resources(screen.proxy)
+		return #missing_resources > 0
+	end
+	return false
+end
 
 --- Unload a preloaded monarch screen
 -- @param id (string|hash) - Id of the screen to unload
@@ -1164,8 +1197,8 @@ end
 -- @return error (string|nil) Error message if unable to send message
 function M.post(id, message_id, message)
 	assert(id, "You must provide a screen id")
-	if not M.is_visible(id) then
+	if not M.is_loaded(id) then
-		return false, "Unable to post message to screen if it isn't visible"
+		return false, "Unable to post message to screen if it isn't loaded"
 	end
 
 	assert(message_id, "You must provide a message_id")
@@ -1173,17 +1206,11 @@ function M.post(id, message_id, message)
 	assert(screens[id], ("There is no screen registered with id %s"):format(tostring(id)))
 
 	local screen = screens[id]
-	if screen.proxy then
 	if screen.receiver_url then
 		log("post() sending message to", screen.receiver_url)
 		msg.post(screen.receiver_url, message_id, message)
 	else
-			return false, "Unable to post message since screen has no receiver url specified"
+		return false, "Unable to post message since screen has no receiver url specified. Set one using monarch.on_post()."
-		end
-	else
-		for id,instance in pairs(screen.factory_ids) do
-			msg.post(instance, message_id, message)
-		end
 	end
 	return true
 end
@@ -1323,24 +1350,36 @@ function M.on_focus_changed(id, fn)
 end
 
 ---
--- Set a function to call when a screen is sent a message using monarch.post()
+-- Set either a function to be called when msg.post() is called on a specific
--- The function will receive (message_id, message, sender)
+-- screen or a URL where the message is sent.
--- IMPORTANT! You must call monarch.on_message() from the same script as
+-- IMPORTANT! If you provide a function you must also make sure to call
--- this function was called
+-- monarch.on_message(message_id, message, sender) from the same script as
+-- this function was called.
 -- @param id Screen id to associate the message listener function with
--- @param fn Message listener function
+-- @param fn_or_url The function to call or URL to send message to
-function M.on_post(id, fn)
+function M.on_post(id, fn_or_url)
 	assert(id, "You must provide a screen id")
-	assert(fn, "You must provide a post receiver function")
 	id = tohash(id)
 	assert(screens[id], ("There is no screen registered with id %s"):format(tostring(id)))
 	local screen = screens[id]
+
+	local t = type(fn_or_url)
+	if t == "function" then
+		screen.receiver_fn = fn_or_url
 		screen.receiver_url = msg.url()
-	screen.receiver_fn = fn
+	elseif t == "userdata" or t == "string" then
+		screen.receiver_fn = nil
+		screen.receiver_url = fn_or_url
+	else
+		screen.receiver_fn = nil
+		screen.receiver_url = msg.url()
+	end
 end
 
+local empty_hash = hash("")
+
 local function url_to_key(url)
-	return (url.socket or hash("")) .. (url.path or hash("")) .. (url.fragment or hash(""))
+	return (url.socket or empty_hash) .. (url.path or empty_hash) .. (url.fragment or empty_hash)
 end
 
 

monarch/screen_proxy.script

@@ -7,9 +7,9 @@ go.property("popup_on_popup", false)
 go.property("timestep_below_popup", 1)
 go.property("screen_keeps_input_focus_when_below_popup", false)
 go.property("others_keep_input_focus_when_below_screen", false)
-go.property("transition_url", msg.url("__DEPRECATED__"))
+go.property("transition_url", msg.url("#__DEPRECATED__"))
-go.property("focus_url", msg.url("__DEPRECATED__"))
+go.property("focus_url", msg.url("#__DEPRECATED__"))
-go.property("receiver_url", msg.url("__DEPRECATED__"))
+go.property("receiver_url", msg.url("#__DEPRECATED__"))
 go.property("preload", false)
 
 

test.settings

@@ -0,0 +1,2 @@
+[bootstrap]
+main_collection = /test/test.collectionc

test/data/screen1.gui_script

@@ -1,5 +1,11 @@
+local monarch
+
 function init(self)
-	print("init - screen1")
+	monarch = require "monarch.monarch"
+	print("init - screen1", msg.url())
+	monarch.on_post("screen1", function(message_id, message, sender)
+		_G.screen1_on_post = message or true
+	end)
 end
 
 function final(self)
@@ -7,7 +13,8 @@ function final(self)
 end
 
 function on_message(self, message_id, message, sender)
+	monarch.on_message(message_id, message, sender)
 	if message_id == hash("foobar") then
-		_G.screen1_foobar = message or true
+		_G.screen1_on_message = message or true
 	end
 end

test/data/screen2.gui_script

@@ -1,5 +1,11 @@
+local monarch
+
 function init(self)
-	print("init - screen2")
+	monarch = require "monarch.monarch"
+	print("init - screen2", msg.url())
+	monarch.on_post("screen2", function(message_id, message, sender)
+		_G.screen2_on_post = message or true
+	end)
 end
 
 function final(self)
@@ -7,7 +13,8 @@ function final(self)
 end
 
 function on_message(self, message_id, message, sender)
+	monarch.on_message(message_id, message, sender)
 	if message_id == hash("foobar") then
-		_G.screen2_foobar = message or true
+		_G.screen2_on_message = message or true
 	end
 end

test/msg.lua

@@ -64,5 +64,17 @@ function M.last(url)
 	return messages[#messages]
 end
 
+function M.filter(url, fn)
+	local t = {}
+	local messages = M.messages(url)
+	for i=1,#messages do
+		local message = messages[i]
+		if fn(message) then
+			t[#t + 1] = message
+		end
+	end
+	return t
+end
+
 
 return M

test/test_monarch.lua

@@ -12,7 +12,6 @@ local FOCUS1 = hash("focus1")
 local BACKGROUND = hash("background")
 local POPUP1 = hash("popup1")
 local POPUP2 = hash("popup2")
-local FOOBAR = hash("foobar")
 local TRANSITION1 = hash("transition1")
 
 local function check_stack(expected_screens)
@@ -156,6 +155,17 @@ return function()
 			assert(wait_until_visible(POPUP1))
 		end)
 
+		it("should be able to tell if a screen is loaded or not", function()
+			assert(not monarch.is_loaded(SCREEN1))
+			monarch.show(SCREEN1)
+			assert(wait_until_visible(SCREEN1))
+			assert(monarch.is_loaded(SCREEN1))
+			
+			monarch.hide(SCREEN1)
+			assert(wait_until_hidden(SCREEN1))
+			assert(not monarch.is_loaded(SCREEN1))
+		end)
+		
 		it("should be able to show a screen without adding it to the stack", function()
 			monarch.show(BACKGROUND, { no_stack = true })
 			assert(wait_until_visible(BACKGROUND), "Background was never shown")
@@ -220,7 +230,7 @@ return function()
 			assert(monarch.data(SCREEN2) == data2, "Expected data on screen2 doesn't match actual data")
 
 			local data_back = { going = "back" }
-			monarch.back(data_back)
+			monarch.back(nil, data_back)
 			assert(wait_until_visible(SCREEN1))
 
 			assert(monarch.data(SCREEN1) == data_back, "Expected data on screen1 doesn't match actual data")
@@ -408,43 +418,37 @@ return function()
 
 			monarch.show(SCREEN1)
 			assert(wait_until_not_busy())
-			assert(mock_msg.messages(URL1)[1].message_id == monarch.SCREEN_TRANSITION_IN_STARTED)
-			assert(mock_msg.messages(URL1)[1].message.screen == SCREEN1)
-			assert(mock_msg.messages(URL2)[1].message_id == monarch.SCREEN_TRANSITION_IN_STARTED)
-			assert(mock_msg.messages(URL2)[1].message.screen == SCREEN1)
-			assert(mock_msg.messages(URL1)[2].message_id == monarch.SCREEN_TRANSITION_IN_FINISHED)
-			assert(mock_msg.messages(URL1)[2].message.screen == SCREEN1)
-			assert(mock_msg.messages(URL2)[2].message_id == monarch.SCREEN_TRANSITION_IN_FINISHED)
-			assert(mock_msg.messages(URL2)[2].message.screen == SCREEN1)
 
 			monarch.remove_listener(URL2)
 			monarch.show(SCREEN2)
 			assert(wait_until_not_busy())
 
-			assert(#mock_msg.messages(URL1) == 6)
-			assert(#mock_msg.messages(URL2) == 2)
-			assert(mock_msg.messages(URL1)[3].message_id == monarch.SCREEN_TRANSITION_IN_STARTED)
-			assert(mock_msg.messages(URL1)[3].message.screen == SCREEN2)
-			assert(mock_msg.messages(URL1)[4].message_id == monarch.SCREEN_TRANSITION_IN_FINISHED)
-			assert(mock_msg.messages(URL1)[4].message.screen == SCREEN2)
-			assert(mock_msg.messages(URL1)[5].message_id == monarch.SCREEN_TRANSITION_OUT_STARTED)
-			assert(mock_msg.messages(URL1)[5].message.screen == SCREEN1)
-			assert(mock_msg.messages(URL1)[6].message_id == monarch.SCREEN_TRANSITION_OUT_FINISHED)
-			assert(mock_msg.messages(URL1)[6].message.screen == SCREEN1)
-
 			monarch.back()
 			assert(wait_until_not_busy())
 
-			assert(#mock_msg.messages(URL1) == 10)
+			local messages = mock_msg.filter(URL1, function(m)
-			assert(#mock_msg.messages(URL2) == 2)
+				return m.message.screen == SCREEN1
-			assert(mock_msg.messages(URL1)[7].message_id == monarch.SCREEN_TRANSITION_IN_STARTED)
+			end)
-			assert(mock_msg.messages(URL1)[7].message.screen == SCREEN1)
+			assert(messages[1].message_id == monarch.SCREEN_TRANSITION_IN_STARTED)
-			assert(mock_msg.messages(URL1)[8].message_id == monarch.SCREEN_TRANSITION_IN_FINISHED)
+			assert(messages[2].message_id == monarch.SCREEN_TRANSITION_IN_FINISHED)
-			assert(mock_msg.messages(URL1)[8].message.screen == SCREEN1)
+			assert(messages[3].message_id == monarch.SCREEN_TRANSITION_OUT_STARTED)
-			assert(mock_msg.messages(URL1)[9].message_id == monarch.SCREEN_TRANSITION_OUT_STARTED)
+			assert(messages[4].message_id == monarch.SCREEN_TRANSITION_OUT_FINISHED)
-			assert(mock_msg.messages(URL1)[9].message.screen == SCREEN2)
+			assert(messages[5].message_id == monarch.SCREEN_TRANSITION_IN_STARTED)
-			assert(mock_msg.messages(URL1)[10].message_id == monarch.SCREEN_TRANSITION_OUT_FINISHED)
+			assert(messages[6].message_id == monarch.SCREEN_TRANSITION_IN_FINISHED)
-			assert(mock_msg.messages(URL1)[10].message.screen == SCREEN2)
+
+			messages = mock_msg.filter(URL2, function(m)
+				return m.message.screen == SCREEN1
+			end)
+			assert(messages[1].message_id == monarch.SCREEN_TRANSITION_IN_STARTED)
+			assert(messages[2].message_id == monarch.SCREEN_TRANSITION_IN_FINISHED)
+			
+			messages = mock_msg.filter(URL1, function(m)
+				return m.message.screen == SCREEN2
+			end)
+			assert(messages[1].message_id == monarch.SCREEN_TRANSITION_IN_STARTED)
+			assert(messages[2].message_id == monarch.SCREEN_TRANSITION_IN_FINISHED)
+			assert(messages[3].message_id == monarch.SCREEN_TRANSITION_OUT_STARTED)
+			assert(messages[4].message_id == monarch.SCREEN_TRANSITION_OUT_FINISHED)
 		end)
 		
 		it("should be able to show a screen even while it is preloading", function()
@@ -491,49 +495,56 @@ return function()
 
 
 		it("should be able to post messages without message data to visible screens", function()
-			_G.screen1_foobar = nil
+			_G.screen1_on_message = nil
-			_G.screen2_foobar = nil
+			_G.screen1_on_post = nil
+			_G.screen2_on_message = nil
+			_G.screen2_on_post = nil
 
 			-- proxy screen
 			monarch.show(SCREEN1)
 			wait_until_visible(SCREEN1)
 			assert(monarch.post(SCREEN1, "foobar"), "Expected monarch.post() to return true")
 			cowait(0.1)
-			assert(_G.screen1_foobar, "Screen1 never received a message")
+			assert(_G.screen1_on_message, "Screen1 never received a message")
+			assert(_G.screen1_on_post, "Screen1 never received a callback")
 
 			-- factory screen
 			monarch.show(SCREEN2)
 			wait_until_visible(SCREEN2)
 			assert(monarch.post(SCREEN2, "foobar"), "Expected monarch.post() to return true")
 			cowait(0.1)
-			assert(_G.screen2_foobar, "Screen2 never received a message")
+			assert(_G.screen2_on_message, "Screen2 never received a message")
+			assert(_G.screen2_on_post, "Screen2 never received a callback")
 		end)
 
 
 		it("should be able to post messages with message data to visible screens", function()
-			_G.screen1_foobar = nil
+			_G.screen1_on_message = nil
-			_G.screen2_foobar = nil
+			_G.screen1_on_post = nil
+			_G.screen2_on_message = nil
+			_G.screen2_on_post = nil
 
 			-- proxy screen
 			monarch.show(SCREEN1)
 			wait_until_visible(SCREEN1)
 			assert(monarch.post(SCREEN1, "foobar", { foo = "bar" }), "Expected monarch.post() to return true")
 			cowait(0.1)
-			assert(_G.screen1_foobar, "Screen1 never received a message")
+			assert(_G.screen1_on_message, "Screen1 never received a message")
-			assert(_G.screen1_foobar.foo == "bar", "Screen1 never received message data")
+			assert(_G.screen1_on_message.foo == "bar", "Screen1 never received message data")
 
 			-- factory screen
 			monarch.show(SCREEN2)
 			wait_until_visible(SCREEN2)
 			assert(monarch.post(SCREEN2, "foobar", { foo = "bar" }), "Expected monarch.post() to return true")
 			cowait(0.1)
-			assert(_G.screen2_foobar, "Screen2 never received a message")
+			assert(_G.screen2_on_message, "Screen2 never received a message")
-			assert(_G.screen2_foobar.foo == "bar", "Screen2 never received message data")
+			assert(_G.screen2_on_message.foo == "bar", "Screen2 never received message data")
 		end)
 
 
 		it("should not be able to post messages to hidden screens", function()
-			_G.screen1_foobar = nil
+			_G.screen1_on_message = nil
+			_G.screen1_on_post = nil
 
 			monarch.show(SCREEN1)
 			monarch.show(SCREEN2)
@@ -542,7 +553,7 @@ return function()
 			local ok, err = monarch.post(SCREEN1, "foobar")
 			assert(not ok and err, "Expected monarch.post() to return false plus an error message")
 			cowait(0.1)
-			assert(not _G.screen1_foobar, "Screen1 should not have received a message")
+			assert(not _G.screen1_on_message, "Screen1 should not have received a message")
 		end)