The underlying technical principles of the Bootstrap framework in the Java class library are detailed

Bootstrap is a popular front -end framework. It is based on HTML, CSS and JavaScript, providing developers with a set of tools and components that are easy to use and functional.Its underlying technical principles mainly include the following aspects. 1. Response network system: Bootstrap uses the adaptive grid system, which can automatically adjust the layout according to the screen size of the device.It divides the page into 12 equivalent columns. By applying the corresponding CSS class on HTML elements, developers can easily achieve multiple columns and show different presentation effects on different devices. html <div class="container"> <div class="row"> <div class = "color-sm-6"> Left content </div> <div class = "color-sm-6"> Right content </div> </div> </div> 2. Modeling components: Bootstrap provides a series of stylish components, such as buttons, navigation bars, forms, forms, etc.These components can quickly build a user interface with consistent appearance and have effective interaction effects.Developers can use these components by applying corresponding CSS classes on the element. html <button class = "btn btn-primary"> Click me </button> <nav class="navbar navbar-expand-lg navbar-light bg-light"> <!-Navigation bar content-> </nav> 3. JavaScript plug -in: Bootstrap built up some commonly used JavaScript plugins, such as rotation diagrams, modal boxes, drop -down menu, etc.These plug -ins can enhance the interaction of the user interface and provide rich functions and effects.Developers can initialize and use these plugins by introducing the corresponding JavaScript files in the page and using these plug -ins. html <script src="bootstrap.js"></script> <script> // Initialized wheel broadcast plug -in $('.carousel').carousel(); // Open the modal box $('#myModal').modal('show'); </script> 4. Response design: Bootstrap supports the response design, which can automatically adjust the layout and style of the page according to different devices.It achieves a responsive effect by using media query and CSS prefix class.Developers can choose different layouts and styles as needed to adapt to different screen size. html <div class="col-lg-4 col-md-6 col-sm-12">内容</div> All in all, Bootstrap is based on HTML, CSS, and JavaScript. It uses the technical principles such as the response -type network system, style component, JavaScript plugin and response design to provide developers with a simple and convenient way to build a modern, response to responseWebsite and applications.It not only provides rich tools and components, but also has a good cross -browser compatibility and easy -to -customize characteristics, enabling developers to quickly build a beautiful and powerful user interface.