Webview for LuaRT released !

Samir

Hi community,

I am particularly proud to present to you the fruit of hard work over the past few months, which will take LuaRT to a new level.

This work now makes it possible to provide a widget capable of rendering HTML/Javascript/CSS content inside a native window, fully integrated into the ui module.

The complexity comes from the fact that this widget is based on the Microsoft Edge Webview2 component, which was not originally intended to work with the mingw-w64 compiler, and with a programming interface rather adapted to .Net frameworks, UWP and WinRT apps. As an added bonus, no other dependencies are required (i.e. no Webview2Loader.dll dependency!).

The work paid off! This new widget, available as a LuaRT binary module, shares the same vision as the LuaRT framework: simplicity, speed and lightness.

With Webview for LuaRT, you will be able to develop modern applications with the latest innovations in terms of Web content (PDF, videos, WebGL...). This means you can build desktop applications using LuaRT for native (backend) and Webview for layout (frontend) using HTML and CSS.

In addition, Webview can be used to display web pages directly within LuaRT applications.

This is similar to Electron, but uses LuaRT instead of NodeJS, and is a lot lighter!

Moreover, the Webview module can also be integrated into the executable when compiling with rtc and loaded from memory without issue.

It's time to show what LuaRT is capable of!

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Regards,

Samir

cos00kun

This is amazing good news. Thank you [Login to see the link] 🙏

steve64

A very promising approach!
However, it would be even more appealing in case of more interaction capability between the Web world and the Lua world. For instance, it would be great to attach Lua callbacks to HTML objects to avoid JavaScript...

Samir

Hi Steve,
Thank you for this feedback.
Javascript is a must on the web and many frameworks dépends on it. A better integration between Lua and javascript is however possible

steve64

How can I embed Webview.dll in my standalone LuaRT application?

require "webview" works fine from the IDE but when I compile to final .exe
the module is not found

cos00kun

Maybe it's not the right method, but I solve this problem by copying it next to the exe file.

Samir

If you want to embed the Webview.dll binary module inside the executable, you should put the main Lua script in the same directory with the DLL and specify the folder on the command line of the rtc compiler :

Let's say we have a main.lua file,
Put in the same directory the Webview.dll binary module
Open a command prompt and go to this folder with the cd command
Then type : rtc.exe -w main.lua .

The . is the current folder that will be embedded inside the executable
To require for the Webview.dll binary module from your script, just use the same require "webview" statement in your main.lua script

Samir

I'm thinking of a new command line option for rtc, to embed a DLL binary module without the need to copy it in a folder

steve64

this is what I tried, but unfortunately does not work on my side...
I have a project folder with a main lua file and the Webview.dll binary module
I compiled with rtc but when I run the exe I get a dialog window with "runtime error: module webview not found"
corresponding to the line where I put require "webview"
I guess that for some reason the Webview.dll file is not embedded by rtc in the final exe file.
I just downloaded Webview.dll (64-bit) and put it in the modules folder, keeping the rest of LuaRT Studio 1.3.2 x64 as it was.
Maybe should I upgrade other files?

Samir

If you still have this error be sure to :

require for webview and not Webview in your script
put the Lua54.dll in the folder alongside the generated executable

steve64

I'm respecting both indications, really strange...

Less urgent but still interesting: how to give focus to the Webview widget? The show() method trick does not seem to work here for this purpose.

Samir

steve64 still interesting: how to give focus to the Webview widget?

I will check this

steve64

I also tried to compile to exe your YouTube example that is simpler than my application.
I have the following files in my folder:

YouTube.wlua
WebView.dll

Then from this folder I generate the YouTube.exe with the command:

rtc -s -w . YouTube.wlua

Launching YouTube.exe I got a "Runtime error" dialog message:

"The procedure entry point lua_registerevent could not be located in the
dynamic link library <my folder path>\webview.dll"

Adding the lua54.dll to the folder and using instead the builld command:

rtc -w . YouTube.wlua

I got the message dialog: The procedure entry point GetCurrentDir could not be located in the
dynamic link library <my folder path>\YouTube.exe"

Samir

Thank your for the feedback on this, I will investigate it

Samir

For me it's working (I tested both on Windows 10/11).
I think it might be related to an old version of rtc ?

You might have an old LuaRT installation ?

steve64

I have this RTC:

rtc
LuaRT 1.3.2 - Lua script to executable compiler.
Copyright (c) 2023, Samir Tine.

It seems depending on the lua54.dll
Using the DLL from LuaRTStudio\bin (525 KB) I can now compile with rtc -w
The exe works including Web View but if I move the same exe to another folder (always with same lua54.dll) the exe does not start anymore.

Still, I can not run rtc -s -w and see the exe starting (should -s already supported for webview?)

Samir

steve64 The exe works including Web View but if I move the same exe to another folder (always with same lua54.dll) the exe does not start anymore.

Very strange... what platform are you using (x64 ? x86 ?) and which Windows version ?

steve64 can not run rtc -s -w and see the exe starting (should -s already supported for webview?)

Static linking should not be used with binary modules as they expect the Lua54.dll

steve64

UPDATE: I can now compile and run my apps with Webview but:
1) I need to use rtc -w and not rtc -w -s so I need to keep a copy of the proper lua54.dll in same path of my exes (this is in line with your last message)
2) I need to keep also webview.dll in same path of exes and lua54.dll (this is not expected)

Samir

steve64
Well I have found that it works correctly with LuaRT x86

Loading x64 DLL from memory is way more complex, hence the crash when compiling executables with Webview module in x64 mode... It's a known bug of the MemoryLoader library LuaRT is using internaly

Maybe I should use another method than in memory loading of DLL... 🤔