logos-dev-boost/templates/ui-app

UI App Templates

This documents what logos-dev-boost init <name> scaffolds for UI apps (implemented in mcp-server/tools/scaffold.ts).

Pure QML (--type ui-qml)

Generated files

• Main.qml — QML entry point, uses logos.callModule() to call backend modules
• metadata.json — "type": "ui_qml", "view": "Main.qml", no "main" field
• flake.nix — mkLogosQmlModule (no preConfigure, no compilation)
• .gitignore — result, build/, .DS_Store

No C++ files

Pure QML apps have no CMakeLists.txt, no C++ source files, and no compilation step. The QML is loaded directly by the host application.

Calling backend modules

var result = logos.callModule("module_name", "method", ["arg1", "arg2"])

The logos bridge is injected by the host (Basecamp or standalone runner).

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QML + C++ Backend (--type ui-qml-backend)

Generated files

• src/<name>.rep — Qt Remote Objects interface definition (PROP + SLOT declarations)
• src/<name>_interface.h — extends PluginInterface, declares Qt plugin interface IID
• src/<name>_plugin.h / src/<name>_plugin.cpp — plugin class inheriting <Pascal>SimpleSource + <Pascal>Interface + <Pascal>ViewPluginBase; uses initLogos() + setBackend(this)
• src/qml/Main.qml — QML frontend using logos.module("name") for typed replica, logos.watch() for async calls
• metadata.json — "type": "ui_qml", "main": "<name>_plugin", "view": "qml/Main.qml"
• CMakeLists.txt — logos_module() with REP_FILE for Qt Remote Objects code generation
• flake.nix — mkLogosQmlModule
• .gitignore — result, build/, .DS_Store

Architecture

The C++ backend runs in a separate isolated process (logos_host), communicating with the QML frontend via Qt Remote Objects IPC. Properties defined in the .rep file auto-sync to QML replicas. Slots are callable from QML via logos.watch().

QML API

• logos.module("name") — returns a typed Qt Remote Objects replica
• logos.isViewModuleReady("name") — checks backend connection status (imperative check, not reactive)
• viewModuleReadyChanged(moduleName, isReady) — signal to listen for via Connections; use this instead of binding isViewModuleReady() in a property
• logos.watch(pendingReply, onSuccess, onError) — handles async slot calls

Note: isViewModuleReady() is a Q_INVOKABLE method. Binding it in a readonly property will not re-evaluate when the state changes. Use a Connections handler on viewModuleReadyChanged plus Component.onCompleted for the initial check.