Question

我是angular 5和FabricJS的新手。我上课时得到了对象var audioSession = AVAudioSession.sharedInstance(); try { audioSession.setCategoryError(AVAudioSessionCategoryAmbient); audioSession.setActiveError(true); } catch(err) { console.log("setting audioSession category failed"); }和方法vrchol。我想将事件添加到changeColor，但这不起作用。

vrchol

this.vrchol.on("mouseover",this.changeColor);

Answer 1

在mouseover事件中，将cachedirty设置为true并呈现对象，以便其反映更改。

演示

var canvas = new fabric.Canvas('c');
var circle = new fabric.Circle({
  radius: 100
});
canvas.add(circle);
circle.on('mouseover', onMouseOver);
circle.on('mouseout', onMouseOut);

function onMouseOver() {
  if (this.fill != 'red') {
    this.set({
      'fill': 'red',
      'dirty': true
    });
    canvas.requestRenderAll();
  }
}

function onMouseOut() {
  if (this.fill == 'red') {
    this.set({
      'fill': 'black',
      'dirty': true
    });
    canvas.requestRenderAll();
  }
}

canvas{
  border:1px solid;
}

<script src="http://cdnjs.cloudflare.com/ajax/libs/fabric.js/2.6.0/fabric.js"></script>
<canvas id='c' width=400 height=400></canvas>

如何在Angular和FabricJS中向对象添加偶数？

1 个答案: