How could I implement my own ` compose` library calling nati

Question

How could I implement my own ` compose` library calling native components in C C++

ventura · Answer

I was digging into Jetpack Compose trying to understand how the native classes are implemented But the components inherit from AWT classes so I wonder if or how it is possible

olonho · Answer

One could use JNI

jim · Answer

Or KotlinNative C Interop <https kotlinlang org docs reference native c interop html> right

ventura · Answer

< jim> it is less about C C++ interop and more about implement the Compose classes with native C C++ components

ventura · Answer

For example if I wish to implement a wrapper to native Qt5

jim · Answer

So you are looking for something like <https cs android com androidx platform frameworks support + androidx main compose ui ui src androidMain kotlin androidx compose ui viewinterop AndroidView kt|AndroidView> except for Qt5

ventura · Answer

touché

ventura · Answer

< jim> the hierarchy is ```androidx compose desktop AppFrame androidx compose desktop AppWindow androidx compose desktop Window``` and `AppFrame` has ```abstract class AppFrame abstract val window ComposeWindow internal var menuBar MenuBar = null ```

ventura · Answer

`ComposeWindow` and `MenuBar` are also androidx classes that internally use `java awt` and `javax swing`

jim · Answer

Yeah there always needs to be some sort of entry point into Compose code We implemented Swing but we would be very open to community contributions that add support for other host ui toolkits

jim · Answer

You may also want to look at <https android review googlesource com c platform frameworks support + 1547075|SwingPanel> which is very much still a work in progress

ventura · Answer

< jim> Well seems to be possible a ugly hack but possible I will try to do a tutorial wink

jim · Answer

In addition to a tutorial feel free to propose any changes that might make it a less ugly hack or which add Qt5 support to compose desktop As I mentioned it wouldn t be a focus for us but we re happy to take contributions Readme is here <https cs android com androidx platform frameworks support + androidx main compose README md> and we re always here in the slack channel to answer any questions

ventura · Answer

< jim> I shall start by studying this tutorial As soon as I finish a demo you will be the first to know Thank you for your help wink

Kirill Grouchnikov · Answer

Long time ago Sun switched the implementation of system look and feel on Windows to use native painting and animation APIs It wasn t a real Windows button instead of a Swing `JButton` but was supposed to be the same calls to paint and animate it It fell straight into the uncanny valley it was 95 there but the last 5 was and still is really noticeable