a day ago
- This demo explains building a custom drag-and-drop system with JavaScript and CSS, using jQuery for ease while implementing core functionality manually.
- The system moves elements by setting their CSS 'position' to 'absolute' and updating 'left' and 'top' properties relative to the container.
- Drag mode is initiated on mousedown, items follow the mouse during move, and on mouseup, the drop is processed with collision detection on droptargets.
- To avoid the element's corner sticking to the mouse, the system remembers the mouse offset on the element at click and adjusts positioning accordingly.
- Mouse coordinates are converted from document space to the container's coordinate system for proper absolute positioning within the container.
- Elements with class 'stayinparent' are restricted to their parent container, while others can move freely across the document.
- Drop containers are marked with class 'droptarget'; on drop, collisions are checked and a 'drop' event is dispatched with the draggable element.
- Usage involves setting 'draggable' and 'droptarget' classes, calling 'beejdnd.init()', and binding a drop event handler with a draggable reference.
- Suggestions for improvements include bounding drag areas, axis restriction, clone creation, scroll-on-edge, multitouch support, and jQuery plugin conversion.
- The code is licensed under the MIT open source license.