Building web applications

Building Applications for the Web

structure Web Applications

WebAssembly is a binary format that allows sand-boxed executable code in web pages. This format is nearly as fast as native machine code, and is now supported by all major web browsers.

WebAssembly It's a binary format , Allow sandboxed executable code in web pages . This format is almost as fast as native machine code , Now all the major web Browsers support this format .

Qt for WebAssembly enables building Qt applications so that they can be integrated into web pages. It doesn't require any client-side installations and reduces the use of server-side resources.

Qt for WebAssembly Support building Qt Applications , In order to integrate them into the web page . It does not require any client installation , And reduce the use of server-side resources .

The experimental WebAssembly plugin enables you to build your applications in WebAssembly format and deploy and run them in the local web browser. You can change the web browser in the project's run settings.

​ Experimental WebAssembly Plug ins enable you to WebAssembly Format build application , And locally web Deploy and run them in the browser . It can be changed in the running settings of the project web browser .

To build applications for the web and run them in a web browser, you need to install Qt for WebAssembly and the tool chain for compiling to WebAssembly.

for web Build the application and put it in web Run them in the browser , Need to install Qt for WebAssembly And are used to compile to WebAssembly The tool chain .

Requirements

Necessary condition

You need the following software to build Qt applications for the web and run them in a browser:

You need the following software for web structure Qt Applications and run them in a browser ：

• Qt for WebAssembly 5.15, or later
• Qt for WebAssembly 5.15 Or later
• On Windows: MinGW 7.3.0, or later
• ​ stay Windows On ：MinGW 7.3.0 Or later
• emscripten tool chain for compiling to WebAssembly
• Used to compile to WebAssembly Of emscripten Tool chain

Setting Up the Development Environment

Build the development environment

You need to install and configure Qt for WebAssembly and the tool chain for compiling to WebAssembly. The Qt Installer automatically adds a build and run kit to Qt Creator.

You need to install and configure Qt for WebAssembly And for compiling to WebAssembly The tool chain .Qt The installer will automatically send to Qt Creator Add build and run kits .

Setting Up Qt for WebAssembly

Set up Qt for WebAssembly

To set up Qt for WebAssembly:

To set up Qt for WebAssembly, Do the following ：

1.Use the Qt maintenance tool to install Qt for WebAssembly and, on Windows, MinGW (found in Developer and Designer Tools).

1、 Use Qt Installation of maintenance tools Qt for WebAssembly, stay Windows Installation on MinGW（ stay Developer and Designer Find... In the tool ）.

2.Check out a known-good Emscripten version supported by the Qt for WebAssembly version that you installed, and install and activate emscripten, as instructed in Install Emscripten.

​2、 Check your installation Qt for WebAssembly Version supports known good Emscripten edition , Then follow the installation Emscripten Install and activate Emscripten.

Enabling the WebAssembly Plugin

Enable WebAssembly plug-in unit

To enable the plugin:

To enable the plug-in , Do the following ：

1.In Qt Creator, select Help > About Plugins > Device Support > WebAssembly.

1、 stay Qt Creator in , Choose help > About plug-ins > Device support >WebAssembly.

2.Select Restart Now to restart Qt Creator and load the plugin.

2、 Select restart now to restart Qt Creator And load the plug-in .

Specifying WebAssembly Settings

Appoint WebAssembly Set up

To configure Qt Creator for building Qt apps for the web:

You want to configure Qt Creator In order to web structure Qt Applications , Do the following ：

1.Select Tools > Options > Devices > WebAssembly.

1、 Select tool > Options > equipment >WebAssembly.

2.In the Emscripten SDK path field, enter the root directory where emsdk is installed.

2、 stay Emscripten SDK In the path field , Input installation emsdk Root directory .

3.Qt Creator configures the Emscripten SDK environment for you if the emsdk is supported by the Qt for WebAssembly version that you will use for developing the application.

3、 If you're going to use for developing applications Qt for WebAssembly Versioning support emsdk, be Qt Creator Will configure... For you Emscripten SDK Environmental Science .

4.Select Tools > Options > Kits.

4、 Select tool > Options > tool kit .

5.In the Compiler group, Emscripten Compiler should have been automatically detected for both C++ and C. If not, check that emscripten is set up correctly.

5、 In the compiler group , Should have automatically detected C++ and C Of Emscripten compiler . If not detected , Please check whether the... Is set correctly Emscripten.

Adding WebAssembly Kits

add to WebAssembly tool kit

The Qt for Web Assembly installation automatically adds build and run kits to Qt Creator. To add kits:

Qt for Web Assembly The installation will automatically send to Qt Creator Add build and run kits . To add a suite ：

1.Select Tools > Options > Kits > Add.

1、 Select tool > Options > tool kit > add to .

2.In the Name field, specify a name for the kit.

2、 In the name field , Specify the name of the suite .

3.In the Device type field, select WebAssembly Runtime. The value of the Device field is automatically set to Web Browser.

3、 In the device type field , choice WebAssembly Runtime. The value of the device field is automatically set to Web browser .

4.In the Compiler field, select Emscripten Compiler for both C and C++.

4、 In the compiler field , by C and C++ choice Emscripten compiler .

5.Select Apply to add the kit.

5、 choice Apply（ application ） Add Kit .

Running Applications in a Web Browser

stay Web Run the application in the browser

To run a project:

To run the project , Do the following ：

1.Open a project for an application you want to run in a web browser.

1、 Open to web The project of the application running in the browser .

2.Select Projects > Build & Run, and then select the WebAssembly kit as the build and run kit for the project.

2、 choice “ project ”>“ Build and run ”, And then choose WebAssembly The toolkit serves as the build and run toolkit for the project .

3.Select Run to specify run settings.

3、 Select run to specify run settings .

4.In the Web browser field, select the browser to run the application in.

4、 stay Web Browser field , Select the browser in which you want to run the application .

You can now build Qt applications in WebAssembly format and run them in a web browser as described in Building for Multiple Platforms and Running on Multiple Platforms.

​ Now? , You can use WebAssembly Format construction Qt Applications , And in web Run them in the browser , Such as “ Build multiple platforms and run on multiple platforms ” Described in .