Fabricjs-copy和paste 

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="../fabric.js"></script>
  <style>
    .controls {
      padding: 20px 0px;
    }

    .canvas-container {
      width: 600px;
      height: 600px;
      border: 1px dotted #ccc;
    }
  </style>
</head>

<body>
  <div class="controls">
    <h5>
      主要通过canvas.getActiveObject().clone实现copy
      <br />
      paste的时候把已clone的对象分别add进canvas
    </h5>
    <button onclick="Copy()">Copy selected objecs</button>
    <button onclick="Paste()">Paste selected objects</button>
  </div>
  <div class="canvas-container">
    <canvas id="c" width="600" height="600"></canvas>
  </div>

  <script>
    let _clipboard = null

    function Paste() {
      if (!_clipboard) {
        alert('请先copy')
        return false
      }
      _clipboard.clone(function(clonedObj) {
        canvas.discardActiveObject(); //禁用已选择的活动对象   取消已选择的对象的选择状态
        clonedObj.set({
          left: clonedObj.left + 10, //设置以下偏移避免重叠
          top: clonedObj.top + 10,
          evented: true
        });
        console.log(clonedObj.type) //rect group    activeSelection多选，shift按下选择的
        if (clonedObj.type === 'activeSelection') {
          clonedObj.canvas = canvas
          clonedObj.forEachObject(function(obj) {
            canvas.add(obj)
          })
          clonedObj.setCoords()
        } else {
          canvas.add(clonedObj)
        }
        _clipboard.top += 10 // 防止重复paste导致图形重叠
        _clipboard.left += 10
        canvas.setActiveObject(clonedObj) //最新paste的元素为选择状态
        canvas.requestRenderAll() //更新 防止setCoords之后obj无法选中
      })
    }

    function Copy() {
      if (!canvas.getActiveObject()) {
        alert('请先选择元素')
        return false
      }
      canvas.getActiveObject() //已选择的对象 可以是对象组，选择多个元素
        .clone(function(cloned) {
          _clipboard = cloned //赋值为全局变量方便paste获取
        })
    }

    //以下是基础操作  以上是重点↑
    var canvas = this.__canvas = new fabric.Canvas('c')
    var rect = new fabric.Rect({
      left: 100,
      top: 50,
      fill: '#D81B60',
      width: 100,
      height: 100,
      strokeWidth: 2,
      stroke: "#880E4F",
      rx: 10,
      ry: 10,
      angle: 45,
      hasControls: true
    });

    canvas.add(rect);

    // create a rectangle object
    var rect2 = new fabric.Rect({
      left: 200,
      top: 50,
      fill: '#F06292',
      width: 100,
      height: 100,
      strokeWidth: 2,
      stroke: "#880E4F",
      rx: 10,
      ry: 10,
      angle: 45,
      hasControls: true
    });

    canvas.add(rect2);
    var circle1 = new fabric.Circle({
      radius: 65,
      fill: '#039BE5',
      left: 0
    });

    var circle2 = new fabric.Circle({
      radius: 65,
      fill: '#4FC3F7',
      left: 110,
      opacity: 0.7
    });
    var group = new fabric.Group([circle1, circle2, ], {
      left: 40,
      top: 450
    });

    canvas.add(group);
  </script>
</body>

</html>

上面注释已经很详细了 偷一下懒

posted @ 2022-03-31 15:58  聂小恶  阅读(182)  评论(0)  编辑  收藏  举报