Javascript 正在加载fabric.image的fabric js子类并应用图像过滤器
加载保存到子类图像对象的图像过滤器时出现问题。下面是我的子类的代码:Javascript 正在加载fabric.image的fabric js子类并应用图像过滤器,javascript,canvas,fabricjs,Javascript,Canvas,Fabricjs,加载保存到子类图像对象的图像过滤器时出现问题。下面是我的子类的代码: fabric.TopImage = fabric.util.createClass(fabric.Image, { type: 'top-image', initialize: function (element, options) { this.callSuper('initialize', element, options); this.set('name', 'top'
fabric.TopImage = fabric.util.createClass(fabric.Image, {
type: 'top-image',
initialize: function (element, options) {
this.callSuper('initialize', element, options);
this.set('name', 'top');
this.set('lockUniScaling', true);
},
toObject: function () {
return fabric.util.object.extend(this.callSuper('toObject'), { name: this.name });
}
});
fabric.TopImage.fromObject = function (object, callback) {
fabric.util.loadImage(object.src, function (img) {
callback && callback(new fabric.TopImage(img, object));
});
};
fabric.TopImage.async = true;
无需应用任何过滤器即可正常工作
我使用以下方法将筛选器添加到此子类的实例:
objectToFilter.filters[0] = new fabric.Image.filters.RemoveWhite({threshold: 20, distance: 20});
objectToFilter.applyFilters(canvas.renderAll.bind(canvas));
保存对象将通过类型、阈值和距离的过滤器对象
但是,加载此对象会在的all.js文件中导致错误:
Uncaught TypeError: Object #<Object> has no method 'applyTo'
uncaughttypeerror:对象#没有方法“applyTo”
由于您从未在此处调用Image.fromObject函数,因此过滤器从未初始化,无法应用。为了使筛选器按预期工作,请改用此函数:
fabric.TopImage.fromObject = function (object, callback) {
fabric.util.loadImage(object.src, function (img) {
var oImg = new fabric.TopImage(img);
oImg._initConfig(object);
oImg._initFilters(object);
callback(oImg);
});
};