HTML5 Canvas 拖拽图像

要使用 Konva 拖拽图像，我们可以在实例化形状时将 draggable 属性设置为 true，或者可以使用 draggable() 方法。draggable() 方法自动启用桌面和移动应用程序的拖拽功能。

Konva 拖拽图像演示view raw

<!DOCTYPE html>
<html>
  <head>
    <script src="https://unpkg.com/konva@9.3.18/konva.min.js"></script>
    <meta charset="utf-8" />
    <title>Konva Drag and Drop an Image Demo</title>
    <style>
      body {
        margin: 0;
        padding: 0;
        overflow: hidden;
        background-color: #f0f0f0;
      }
    </style>
  </head>
  <body>
    <div id="container"></div>
    <script>
      var width = window.innerWidth;
      var height = window.innerHeight;

      function drawImage(imageObj) {
        var stage = new Konva.Stage({
          container: 'container',
          width: width,
          height: height,
        });

        var layer = new Konva.Layer();
        // darth vader
        var darthVaderImg = new Konva.Image({
          image: imageObj,
          x: stage.width() / 2 - 200 / 2,
          y: stage.height() / 2 - 137 / 2,
          width: 200,
          height: 137,
          draggable: true,
        });

        // add cursor styling
        darthVaderImg.on('mouseover', function () {
          document.body.style.cursor = 'pointer';
        });
        darthVaderImg.on('mouseout', function () {
          document.body.style.cursor = 'default';
        });

        layer.add(darthVaderImg);
        stage.add(layer);
      }
      var imageObj = new Image();
      imageObj.onload = function () {
        drawImage(this);
      };
      imageObj.src = '/assets/darth-vader.jpg';
    </script>
  </body>
</html>