Chandra - Perl bindings to webview-c

A Perl module for building cross-platform GUI applications using web technologies (HTML/CSS/JS) powered by webview-c.

Synopsis

use Chandra;

# Simple usage - one liner
Chandra->new(
    title  => 'Hello World',
    url    => 'https://perl.org',
)->run;

# Using HTML directly
Chandra->new(
    title => 'My App',
    url   => 'data:text/html,<h1>Hello from Perl!</h1><button onclick="external.invoke(\'clicked\')">Click me</button>',
    callback => sub {
        my ($msg) = @_;
        print "JavaScript sent: $msg\n";
    },
)->run;

# Advanced: manual event loop
my $app = Chandra->new(
    title => 'Counter',
    url   => 'data:text/html,<div id="n">0</div>',
    debug => 1,
);

$app->init;

my $count = 0;
while ($app->loop(0) == 0) {
    # Non-blocking loop - could do other Perl work here
    $app->eval_js(sprintf('document.getElementById("n").textContent = %d', ++$count));
    select(undef, undef, undef, 0.1);  # Sleep 100ms
}

$app->exit;

Building

Prerequisites

macOS:

• Xcode Command Line Tools (provides WebKit framework)

Linux:

sudo apt-get install libgtk-3-dev libwebkit2gtk-4.0-dev

Windows:

• MinGW with WebView2 SDK (see webview-c docs)

Build Steps

# Download webview-c headers
mkdir -p include
curl -sL https://raw.githubusercontent.com/javalikescript/webview-c/master/webview.h -o include/webview.h
curl -sL https://raw.githubusercontent.com/javalikescript/webview-c/master/webview-cocoa.c -o include/webview-cocoa.c
curl -sL https://raw.githubusercontent.com/javalikescript/webview-c/master/webview-gtk.c -o include/webview-gtk.c

# Build
perl Makefile.PL
make
make test

# Try it
perl -Mblib -e 'use Chandra; Chandra->new(title => "Test", url => "https://perl.org")->run'

API

Chandra->new(%opts)

Create a new Chandra instance.

| Option | Default | Description | |--------|---------|-------------| | title | 'Chandra' | Window title | | url | 'about:blank' | Initial URL or data: URI | | width | 800 | Window width | | height | 600 | Window height | | resizable | 1 | Allow window resizing | | debug | 0 | Enable dev tools (right-click inspect) | | callback | undef | Perl sub for JS -> Perl calls |

Methods

• $app->run() - Simple blocking run
• $app->init() - Initialize for manual loop control
• $app->loop($blocking) - Process events (returns non-zero to exit)
• $app->eval_js($code) - Execute JavaScript
• $app->set_title($title) - Change window title
• $app->terminate() - Signal loop to exit
• $app->exit() - Cleanup

JS -> Perl Communication

Call window.external.invoke("message") from JavaScript. The callback receives the string.

Chandra->new(
    url => 'data:text/html,<button onclick="external.invoke(JSON.stringify({action:\'save\'}))">Save</button>',
    callback => sub {
        my $data = decode_json($_[0]);
        # Handle $data->{action}
    },
)->run;

Roadmap

See PLAN.md for the comprehensive development plan.

License

MIT (same as webview-c)