webview

A tiny cross-platform webview library for C/C++/Go to build modern cross-platform GUIs.

The goal of the project is to create a common HTML5 UI abstraction layer for the most widely used platforms.

It supports two-way JavaScript bindings (to call JavaScript from C/C++/Go and to call C/C++/Go from JavaScript).

It uses Cocoa/WebKit on macOS, gtk-webkit2 on Linux and Edge on Windows 10.

API Documentation

API Documentation is available online for this repository and all available bindings at https://webview.dev.

Contributions to the documentation are managed at https://github.com/webview/docs.

Bindings

This repository contains bindings for C, C++, and Go. Bindings for other languages are maintained separately.

• Rust
• Python
• Nim
• Haskell
• C#
• Janet
• Crystal
• Java
• Ruby
• Pascal

Instructions for Go and C/C++ are included below.

Webview for Go developers

Getting started

Install this library with go get:

$ go get github.com/webview/webview

Import the package and start using it:

package main

import "github.com/webview/webview"

func main() {
	debug := true
	w := webview.New(debug)
	defer w.Destroy()
	w.SetTitle("Minimal webview example")
	w.SetSize(800, 600, webview.HintNone)
	w.Navigate("https://en.m.wikipedia.org/wiki/Main_Page")
	w.Run()
}

Build the app:

# Linux
$ go build -o webview-example && ./webview-example

# MacOS uses app bundles for GUI apps
$ mkdir -p example.app/Contents/MacOS
$ go build -o example.app/Contents/MacOS/example
$ open example.app # Or click on the app in Finder

# Windows requires special linker flags for GUI apps.
# It's also recommended to use TDM-GCC-64 compiler for CGo.
# http://tdm-gcc.tdragon.net/download
$ go build -ldflags="-H windowsgui" -o webview-example.exe

For more details see godoc.

Webview for C/C++ developers

Download webview.h and include it in your C/C++ code. Other dependencies are descibed in the Notes section and at https://webview.dev/.

C++

// main.cc
#include "webview.h"
#ifdef WIN32
int WINAPI WinMain(HINSTANCE hInt, HINSTANCE hPrevInst, LPSTR lpCmdLine,
                   int nCmdShow) {
#else
int main() {
#endif
  webview::webview w(true, nullptr);
  w.set_title("Minimal example");
  w.set_size(480, 320, WEBVIEW_HINT_NONE);
  w.navigate("https://en.m.wikipedia.org/wiki/Main_Page");
  w.run();
  return 0;
}

Build it:

# Linux
$ c++ main.cc `pkg-config --cflags --libs gtk+-3.0 webkit2gtk-4.0` -o webview-example
# MacOS
$ c++ main.cc -std=c++11 -framework WebKit -o webview-example
# Windows (x64)
$ script/build.bat

C

// main.c
#define WEBVIEW_HEADER
#include "webview.h"
#include <stddef.h>

#ifdef WIN32
int WINAPI WinMain(HINSTANCE hInt, HINSTANCE hPrevInst, LPSTR lpCmdLine,
                   int nCmdShow) {
#else
int main() {
#endif
	webview_t w = webview_create(0, NULL);
	webview_set_title(w, "Webview Example");
	webview_set_size(w, 480, 320, WEBVIEW_HINT_NONE);
	webview_navigate(w, "https://en.m.wikipedia.org/wiki/Main_Page");
	webview_run(w);
	webview_destroy(w);
	return 0;
}

Define C++ flags for the platform:

# Linux
$ CPPFLAGS="`pkg-config --cflags --libs gtk+-3.0 webkit2gtk-4.0` -lstdc++"
# MacOS
$ CPPFLAGS="-std=c++11 -framework WebKit"
# Windows (x64) uses the build script

Build it:

$ g++ -c $CPPFLAGS webview.cc -o webview.o  # build webview
$ gcc -c main.c -o main.o  # build C program
$ script/build.bat

For a complete C example see: https://github.com/webview/webview_c

On Windows it is possible to use webview library directly when compiling with cl.exe, but WebView2Loader.dll is still required. To use MinGW you may dynamically link the prebuilt webview.dll (this approach is used in Cgo bindings).

Full C/C++ API is described at the top of webview.h and at https://webview.dev.

Windows Build Script Details

Our build.bat script is currently the only supported way to build a webview executable on Windows. It automatically installs and builds all needed dependancies before compiling your C++ application. It is easy to modify the build script for anyone's specific use case. For instance: you can easily change the Webview2 nuget package version or the compiler's target architecture. We will distribute stable dlls with every release for convenience. If you do not include them in your project, the build script will build them for you anyway - this applies to GO users as well.

Distributing webview apps

On Linux you get a standalone executable. It depends on GTK3 and GtkWebkit2. Include those dependencies if you distribute in a package like DEB or RPM. An application icon can be specified by providing a .desktop file.

On MacOS you are likely to ship an app bundle. Make the following directory structure and just zip it:

example.app
└── Contents
    ├── Info.plist
    ├── MacOS
    |   └── example
    └── Resources
        └── example.icns

Here, Info.plist is a property list file and *.icns is a special icon format. You can convert PNG to icns online or with a tool like icnsutils.

On Windows, you can use a custom icon by providing a resource file, compiling it and linking with it. Typically, windres is used to compile resources.

Also, on Windows, webview.dll and WebView2Loader.dll must be placed into the same directory with the app executable.

To cross-compile a webview app - use xgo.

Notes

• A webview is not a full web browser. Although they may work, we do not support alert, confirm and prompt dialogs. Additionally, console.* methods are not supported.
• Ubuntu users need to install the webkit2gtk-4.0 as development dependency via sudo apt install webkit2gtk-4.0. If the package can't be found webkit2gtk-4.0-dev may be used instead.
• FreeBSD is also supported via webkit2 which may be installed by running pkg install webkit2-gtk3.
• Execution on OpenBSD requires wxallowed mount(8) option.
• On Windows, users must install:
  • Windows 10 SDK via Visual Studio Installer
  • C++ support via Visual Studio Installer
  • Webview2 (you may already have this) download from Microsoft
• Calling Eval() or Dispatch() before Run() does not work, because the webview instance has only configured, but not started yet.

License

Code is distributed under MIT license, feel free to use it in your proprietary projects as well.