**HomeScreen GUI Application / HomeScreen Service Guide** ====
Revision: 0.1
TOYOTA MOTOR CORPORATION
Advanced Driver Information Technology
21th/Nov/2018
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## Table of content - [Target reader of this document](#Target\ reader\ of\ this\ document) - [Overview](#Overview) - [Getting Start](#Getting\ Start) - [Supported environment](#Supported\ environment) - [Build](#Build) - [Configuring](#Configuring) - [How to call HomeScreen APIs from your Application?](#How\ to\ call\ HomeScreen\ APIs\ from\ your\ Application?) - [Supported usecase](#Supported\ usecase) - [Software Architecture](#Software\ Architecture) - [API reference](#API\ reference) - [Sequence](#Sequence) - [Initialize](###Initialize\ Sequence) - [Tap Shortcut(deprecated)](###Tap\ Shortcut\ Sequence) - [ShowWindow](###ShowWindow\ Sequence) - [On Screen Message / Reply Sequence(deprecated)](###On\ Screen\ Message\ /\ Reply\ Sequence) - [ShowOnscreen](###ShowOnscreen\ Sequence) - [ShowNotification](###ShowNotification\ Sequence) - [ShowInformation](###ShowInformation\ Sequence) - [Sample code](#Sample\ code) - [Limitation](#Limitation) - [Next Plan](#Next\ Plan) - [Appendix](#Appendix) * * *
## Target reader of this document Application developer whose software uses HomeScreen. * * *
## Overview HomeScreen is built with a GUI application created with Qt(referred as HomeScreenGUI), and a service running on afb-daemon (referred as HomeScreenBinder). HomeScreen can start/switch applications run in AGL, also displays information such as onscreen messages. You can find these projects in AGL gerrit. homescreen(HomeScreenGUI): https://gerrit.automotivelinux.org/gerrit/#/admin/projects/apps/homescreen launcher(LauncherGUI) https://gerrit.automotivelinux.org/gerrit/#/admin/projects/apps/launcher agl-service-homescreen(HomeScreenBinder's binding library): https://gerrit.automotivelinux.org/gerrit/#/admin/projects/apps/agl-service-homescreen libhomescreen(library for application to communication with HomeScreenBinder): https://gerrit.automotivelinux.org/gerrit/#/admin/projects/src/libhomescreen libqthomescreen(library for qt application to communication with HomeScreenBinder based on libhomescreen) https://gerrit.automotivelinux.org/gerrit/#/admin/projects/src/libqthomescreen Also HomeScreenGUI is using libwindowmanager.
## Getting Start
### Supported environment | Item | Description | |:------------|:----------------------------------| | AGL version | Electric Eel | | Hardware | Renesas R-Car Starter Kit Pro(M3) |
### Build **Download recipe** ``` $ mkdir WORK $ cd WORK $ repo init -u https://gerrit.automotivelinux.org/gerrit/AGL/AGL-repo $ repo sync ``` Then you can find the following recipes. * `meta-agl-demo/recipes-demo-hmi/homescreen` * `meta-agl-devel/meta-hmi-framework/recipes-demo-hmi/launcher` * `meta-agl-demo/recipes-demo-hmi/agl-service-homescreen` * `meta-agl-demo/recipes-demo-hmi/libhomescreen` * `meta-agl-devel/meta-hmi-framework/recipes-demo-hmi/qlibhomescreen` **Bitbake** ``` $ source meta-agl/scripts/aglsetup.sh -m m3ulcb agl-demo agl-devel agl-appfw-smack agl-hmi-framework $ bitbake agl-demo-platform ``` * * *
### Configuring To use HomeScreen API, an application shall paste the following configuration definition into "config.xml" of application. ``` ``` * * *
### How to call HomeScreen APIs from your Application? HomeScreen provides a library which is called "libhomescreen". This library treats "json format" as API calling. For example, if an application wants to call "showWIndow()" API, the you should implement as below. At first the application should create the instance of libhomescreen. ``` LibHomeScreen* libhs; libhs = new LibHomeScreen(); libhs->init(port, token); ``` The port and token is provided by Application Framework Execute the "showWindow()" function. ``` libhs->showWindow("application_id", "display_area"); ``` Regarding the detail of showWindow() API, please refer [this](#HomeScreen\ API) section. The first parameter is the appid of application which want to display,liked "dashboard". And the second parameter corresponds to display_area which defined by windowmanager,usually "normal", so in this case "showWindow" the two parameters are proper string. See also our [Sample code](#Sample\ code).
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## Supported usecase 1. HomeScreenGUI sending showWindow event to applications - Applications using libhomescreen to subscribe the showWindow event, HomeScreenGUI will send showWindow event to applications. 2. Display OnScreen messages(deprecated) - Applications sending OnScreen messages to homescreen-service, and OnScreenAPP will get these message and display. 3. Get OnSreen Reply event(deprecated) - When OnScreen messages is displaying, OnScreenAPP will send a reply event to applications. 4. Display OnScreen by showWindow - When application who want to show OnScreen,it can call "showWindow",then OnScreenApp will display request OnScreen. 5. Hide OnScreen by hideWindow - When application who want to hide OnScreen which is displaying,it can call "hideWindow",then OnScreenApp will hide OnScreen. 6. Send OnScreen Reply by replyShowWindow - When user touch the button of OnScreen, OnScreenApp can call "relplyShowWindow" to send reply information back to application. 7. Show Notification on HomeScreenGUI - When application who want to display a notification,it can call "showNotification",then HomeScreenGUI will display the notification contents on the screen top area. 8. Show Information on HomeScreenGUI - When application who want to display a information,it can call "showInformation",then HomeScreenGUI will display the information contents on the screen bottom area. * * *
## Software Architecture The architecture of HomeScreen is shown below. HomeScreen is the service designed to be used by multiple applications. Therefore HomeScreen framework consists on two binder layers. Please refer the following figure. The upper binder is for application side security context for applications. The lower binder is for servide side security context. Usually application side binder has some business logic for each application, so the number of binders depend on the number of applications which use HomeScreen. On the other hand, regarding lower binder there is only one module in the system. This binder receives all messages from multiple applications (in detail, it comes from upper layer binder). The communication protocols between libhomescreen and upper binder, upper binder and lower binder, lower binder (homescreen-binding) are WebSocket. ![software-stack.png](parts/software-stack.png) * * *
## API reference "libhomescreen" and "agl-service-homescreen" provides several kinds of APIs.
### HomeScreen Specific API - [LibHomeScreen ()](api-ref/html/de/dd0/class_lib_home_screen.html#a724bd949c4154fad041f96a15ef0f5dc) - [init (const int port, const std::string &token)](api-ref/html/de/dd0/class_lib_home_screen.html#a6a57b573cc767725762ba9beab032220) - [tapShortcut(const char *application_id)](api-ref/html/de/dd0/class_lib_home_screen.html#a6ca8ff4a2aa019a735afaff713e0ef44) - [onScreenMessage(const char *display_message)](api-ref/html/de/dd0/class_lib_home_screen.html#ac336482036a72b51a822725f1929523c) - [onScreenReply(const char *reply_message)](api-ref/html/de/dd0/class_lib_home_screen.html#a6c065f41f2c5d1f58d2763bfb4da9c37) - [registerCallback (void(*event_cb)(const std::string &event, struct json_object *event_contents), void(*reply_cb)(struct json_object *reply_contents), void(*hangup_cb)(void)=nullptr)](api-ref/html/de/dd0/class_lib_home_screen.html#a2789e8a5372202cc36f48e71dbb9b7cf) - [set\_event\_handler(enum EventType et, handler_func f)](api-ref/html/de/dd0/class_lib_home_screen.html#ab1b0e08bf35415de9064afed899e9f85) - [call (const string& verb, struct json_object* arg)](api-ref/html/de/dd0/class_lib_home_screen.html#a527b49dcfe581be6275d0eb2236ba37f) - [call (const char* verb, struct json_object* arg)](api-ref/html/de/dd0/class_lib_home_screen.html#ab5e8e8ab7d53e0f114e9e907fcbb7643) - [subscribe (const string& event_name)](api-ref/html/de/dd0/class_lib_home_screen.html#aa4c189807b75d070f567967f0d690738) - [unsubscribe (const string& event_name)](api-ref/html/de/dd0/class_lib_home_screen.html#aac03a45cbd453ba69ddb00c1016930a6) - [showWindow (const char* application_id, json_object* json)](api-ref/html/de/dd0/class_lib_home_screen.html#a69fc770cb3f94d30a10c2c8c81eb892f) - [hideWindow (const char* application_id)](api-ref/html/de/dd0/class_lib_home_screen.html#a4dbaea6c7b310e8ce7207155ff11b32a) - [replyShowWindow (const char* application_id, json_object* json)](api-ref/html/de/dd0/class_lib_home_screen.html#a6310b129fc85ef0623e2e2063950cc4b) - [showNotification (json_object* json)](api-ref/html/de/dd0/class_lib_home_screen.html#a93ad567ed597a80a344ba82457c2bd7f) - [showInformation (json_object* json)](api-ref/html/de/dd0/class_lib_home_screen.html#ada999aeb0444c964428bdf1ee236727f) * * *
## Sequence
### Initialize Sequence ![initialize-set-event-handler](parts/initialize-set-event-handler.svg)
### Tap Shortcut Sequence ![tap_shortcut.svg](parts/tap_shortcut.svg)
### ShowWindow Sequence ![showWindow.svg](parts/showWindow.svg)
### On Screen Message / Reply Sequence ![on_screen_message.svg](parts/on_screen_message.svg)
### ShowOnScreen Sequence ![showOnScreen.svg](parts/showOnScreen.svg)
### ShowNotification Sequence ![showNotification.svg](parts/showNotification.svg)
### ShowInformation Sequence ![showInformation.svg](parts/showInformation.svg)
# Sample code You can find sample implementation of HomeScreen as below. * `libhomescreen/sample/simple-egl` * `libhomescreen/sample/template` # Limitation Now OnScreenApp is developing,approximately it will finished at GG. # Next Plan None. # Appendix ``` @startuml title Application initialization phase entity App entity HomeScreenBinder entity HomeScreenGUI App->HomeScreenBinder: init(port, token) App->HomeScreenBinder: set_event_handler() note over HomeScreenBinder setup event handler the App wishes to receive ・LibHomeScreen::Event_ShowWindow ・LibHomeScreen::Event_HideWindow ・LibHomeScreen::Event_ReplyShowWindow end note @enduml ``` ``` @startuml title Application Callback Event TapShortcut phase entity App entity HomeScreenBinder entity HomeScreenGUI App->HomeScreenBinder: set_event_handler() note over App LibHomeScreen::Event_TapShortcut end note HomeScreenGUI->HomeScreenBinder: tapShortcut(application_id) HomeScreenBinder->App: event_handler(application_id) @enduml ``` ``` @startuml title Application callback event showWindow phase actor user entity "homescreen-service" as hss entity launcher entity App entity windowmanager as wm user-->launcher: tap app's icon launcher->hss: showWindow() note over hss,App {"application_id":"tapped application id", "parameter":{"area":"display area", ...}} end note hss->App: push showWindow event App->wm: activateWindow("application_name","display area") wm-->App: push syncDraw event App->App: display @enduml ``` ``` @startuml title Application Callback Event On Screen Message / Reply phase entity App entity HomeScreenBinder entity HomeScreenGUI HomeScreenGUI->HomeScreenBinder: set_event_handler() note over HomeScreenGUI LibHomeScreen::Event_OnScreenMessage end note App->HomeScreenBinder: set_event_handler() note over App LibHomeScreen::Event_OnScreenReply end note App->HomeScreenBinder: onScreenMessage(display_message) HomeScreenBinder->HomeScreenGUI: event_handler(display_message) HomeScreenGUI->HomeScreenBinder: onScreenReply(reply_message) HomeScreenBinder->App: event_handler(reply_message) @enduml ``` ``` @startuml title show/hide onscreen phase actor user entity "homescreen-service" as hss entity App entity onscreenapp entity windowmanager as wm == show onscreen == user->App: the operation request onscreen App->hss: showWindow() note over App,hss {"application_id":"onscreenapp", "parameter":{"area":"display area", "file":"qml file path", "data":{"the datas to onscreen qml"}}} end note hss->onscreenapp: push showWindow event note over hss,onscreenapp {"application_id":"onscreenapp", "parameter":{"area":"display area", "file":"qml file path", "data":{"the datas to onscreen qml"}, "replyto":"caller application id" }} end note onscreenapp->onscreenapp: get and save parameters onscreenapp->wm: activateWindow("onscreeapp", "display area") alt can show wm-->onscreenapp: push syncDraw event onscreenapp->wm: endDraw("onscreeapp") onscreenapp->onscreenapp: load and display qml file else can't show note over onscreenapp,wm do nothing end note end == hide onscreen == user->onscreenapp: tap onscreen's button onscreenapp->hss: replyShowWindow() note over onscreenapp,hss {"application_id":"the application id who called onscreenapp", "parameter": {"buttonName": "VOLUME_UP", "buttonPressMode": "shortPress", "buttonPressState": "release"}} end note hss->App: push replyShowWindow event App->App: call reply function App->hss: hideWindow("onscreenapp") hss->onscreenapp: push hideWindow event note over hss,onscreenapp {"application_id":"request hideWindow application id"} end note onscreenapp->wm: deactivateWindow("onscreenapp"); onscreenapp->onscreenapp: hide window @enduml ``` ``` @startuml title show notification on HomeScreen top area entity "homescreen-service" as hss entity homescreen entity App App->hss: showNotification() note over App,hss {"icon":"display icon", "text":"display text"} end note hss-> homescreen: push showNotification event note over hss,homescreen {"application_id":"request application id", "parameter":{"icon":"display icon", "text":"display text"}} end note homescreen->homescreen: display notification message 3s @enduml ``` ``` @startuml title show information on HomeScreen bottom area entity "homescreen-service" as hss entity homescreen entity App App->hss: showInformation() note over hss {"info":"display information"} end note hss-> homescreen: push showInformation event homescreen->homescreen: display information message 3s @enduml ```