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QML is NOT a browser stack though. QML is just a way for you to script QObjects. QtQuick - on the other hand - is a very performant GPU accelerated scenegraph t

QML is NOT a browser stack though. QML is just a way for you to script QObjects. QtQuick - on the other hand - is a very performant GPU accelerated scenegraph that can be scripted using QML. > The point is to keep my code in C++ and not hop around to x different files to make sense of my application. Another point of view that differs from this is - QML lets you easily separate UI logic from business logic, to better make sense of your application. Especially when it comes to "responsive applications". For eg. All the UI related parts of your application stay in QML files in folders like desktop/ android/ common/ etc... All the "backend logic" stays in C++, ready to be used by all these UI elements. It is not about being forced to write JS. Nothing stopping you from writing very declarative looking C++ either (fun article: https://woboq.com/blog/property-bindings-in-cpp.html https://woboq.com/blog/property-bindings-in-cpp.html ). It is just about using a better tool for the job. State machines. Reactive properties. Declarative UI description. All of these make you need a lot less code than writing everything in imperative c++.

righthand 3y ago
It’s not a browser stack but includes an HTML painter and V8 engine in your project? This sounds pretty close to a browser stack to me. If this isn’t true then this is one of the confusing aspects. In including pieces of a browser stack or whatever is going on doesn’t really help it make it look not like one. It seems like the ideas are obfuscated just to call it something else.
- jenadine 3y ago
  I think it doesn't include a V8 engine anymore. Qt has its own JS implementation as far as I know. And it doesn't have a full html painter (If you don't use QtWebEngine)
  - saidinesh5 3y ago
    Initially QmlEngine used to use v8 for the javascript interpreter around Qt 5.0. They quickly migrated away from that to their own interpreter for various reasons: https://forum.qt.io/topic/32701/qt-v8/4 https://forum.qt.io/topic/32701/qt-v8/4
- saidinesh5 3y ago
  HTML painter? you mean how QLabel supports rich text via. HTML tags? Not sure what you are getting at with the "ideas are obfuscated to call it something else". You'd have a widget tree/graph even with QWidgets/QObjects. Would you call any QWidget program that uses QJsEngine "a browser stack"?. QML is just a declarative programming language, that lets you script QObject properties/react to signals/property changes. NumberInput { id: width } NumberInput { id: height } Label { text: "Area value is: " + width.value * height.value // automatically gets updated } All expressions in the above snippet of code are basically Javascript expressions. To accomplish the same in pure C++, you'd need to implement some kind of observer pattern/manually connect signals and slots across objects to allow for updates of dependent values (Label's text). QtQuick is a scenegraph that uses QML to render a GPU accelerated UI. Which is what is needed on embedded/mobile UIs to get smooth high performant animated GUIs. That'd be too ineffecient and cumbersome to accomplish with QWidget/C++.
  - righthand 3y ago
    In QWidget if you use it then it’s compiled into the application. If you use QML it’s always there as far as I understand. Please review this post which seems to indicate that JS and HTML components are added to a project when QML is used.[0] It may not be a full engine but as I’ve previously stated I’m not interested in writing things in multiple languages. I want as few extra languages as possible. To tell me it’s not a browser stack then go on about how to use QML you can declare pages in HTML and JS that are then compiled into the binary that passes data between C++ and JS is entirely ignorant of my initial goals. If I wanted to use browser technology and JS I would build my app for a browser. > To accomplish the same in pure C++, you'd need to implement some kind of observer pattern/manually connect signals and slots across objects to allow for updates of dependent values (Label's text). I do not find that extra work because it’s represented in the class itself and the observer pattern maintains my preferences. Perhaps these technologies are useful for those who want to quickly write a mobile app with slick animations. Indeed it is a easy way for Qt to gain audience for those types of apps especially for people who aren’t able to learn C++. For my intentions I am looking for less overhead overall to keep files as pure C++ as possible to ensure that a class I’m writing represents the full scope of it’s functionality and domain. [0] https://news.ycombinator.com/item?id=38395603 https://news.ycombinator.com/item?id=38395603

righthand 3y ago

It’s not a browser stack but includes an HTML painter and V8 engine in your project? This sounds pretty close to a browser stack to me. If this isn’t true then this is one of the confusing aspects. In including pieces of a browser stack or whatever is going on doesn’t really help it make it look not like one. It seems like the ideas are obfuscated just to call it something else.

jenadine 3y ago
I think it doesn't include a V8 engine anymore. Qt has its own JS implementation as far as I know. And it doesn't have a full html painter (If you don't use QtWebEngine)
- saidinesh5 3y ago
  Initially QmlEngine used to use v8 for the javascript interpreter around Qt 5.0. They quickly migrated away from that to their own interpreter for various reasons: https://forum.qt.io/topic/32701/qt-v8/4 https://forum.qt.io/topic/32701/qt-v8/4
saidinesh5 3y ago
HTML painter? you mean how QLabel supports rich text via. HTML tags? Not sure what you are getting at with the "ideas are obfuscated to call it something else". You'd have a widget tree/graph even with QWidgets/QObjects. Would you call any QWidget program that uses QJsEngine "a browser stack"?. QML is just a declarative programming language, that lets you script QObject properties/react to signals/property changes. NumberInput { id: width } NumberInput { id: height } Label { text: "Area value is: " + width.value * height.value // automatically gets updated } All expressions in the above snippet of code are basically Javascript expressions. To accomplish the same in pure C++, you'd need to implement some kind of observer pattern/manually connect signals and slots across objects to allow for updates of dependent values (Label's text). QtQuick is a scenegraph that uses QML to render a GPU accelerated UI. Which is what is needed on embedded/mobile UIs to get smooth high performant animated GUIs. That'd be too ineffecient and cumbersome to accomplish with QWidget/C++.
- righthand 3y ago
  In QWidget if you use it then it’s compiled into the application. If you use QML it’s always there as far as I understand. Please review this post which seems to indicate that JS and HTML components are added to a project when QML is used.[0] It may not be a full engine but as I’ve previously stated I’m not interested in writing things in multiple languages. I want as few extra languages as possible. To tell me it’s not a browser stack then go on about how to use QML you can declare pages in HTML and JS that are then compiled into the binary that passes data between C++ and JS is entirely ignorant of my initial goals. If I wanted to use browser technology and JS I would build my app for a browser. > To accomplish the same in pure C++, you'd need to implement some kind of observer pattern/manually connect signals and slots across objects to allow for updates of dependent values (Label's text). I do not find that extra work because it’s represented in the class itself and the observer pattern maintains my preferences. Perhaps these technologies are useful for those who want to quickly write a mobile app with slick animations. Indeed it is a easy way for Qt to gain audience for those types of apps especially for people who aren’t able to learn C++. For my intentions I am looking for less overhead overall to keep files as pure C++ as possible to ensure that a class I’m writing represents the full scope of it’s functionality and domain. [0] https://news.ycombinator.com/item?id=38395603 https://news.ycombinator.com/item?id=38395603