[adapters] 增加小游戏适配部分源码

adapters/platforms/taobao-minigame/wrapper/builtin/Canvas.js

@@ -0,0 +1,77 @@
+import { innerWidth, innerHeight } from './WindowProperties'
+
+function Canvas () {}
+
+let CanvasProxy = new Proxy(Canvas, {
+  construct () {
+
+    const canvas = my.createCanvas()
+
+    canvas.type = 'canvas'
+  
+    // canvas.__proto__.__proto__.__proto__ = new HTMLCanvasElement()
+  
+    const _getContext = canvas.getContext
+  
+    canvas.getBoundingClientRect = () => {
+      const ret = {
+        top: 0,
+        left: 0,
+        width: window.innerWidth,
+        height: window.innerHeight
+      }
+      return ret
+    }
+  
+    canvas.style = {
+      top: '0px',
+      left: '0px',
+      width: innerWidth + 'px',
+      height: innerHeight + 'px',
+    }
+  
+    canvas.addEventListener = function (type, listener, options = {}) {
+      // console.log('canvas.addEventListener', type);
+      if (my.isIDE) {
+        $global.document.addEventListener(type, listener, options);
+      }
+    }
+  
+    canvas.removeEventListener = function (type, listener) {
+      // console.log('canvas.removeEventListener', type);
+      if (my.isIDE) {
+        $global.document.removeEventListener(type, listener);
+      }
+    }
+  
+    canvas.dispatchEvent = function (event = {}) {
+      // console.log('canvas.dispatchEvent' , event.type, event);
+      if (my.isIDE) {
+        $global.document.dispatchEvent(event);
+      }
+    }
+  
+    Object.defineProperty(canvas, 'clientWidth', {
+      enumerable: true,
+      get: function get() {
+        return innerWidth
+      }
+    })
+  
+    Object.defineProperty(canvas, 'clientHeight', {
+      enumerable: true,
+      get: function get() {
+        return innerHeight
+      }
+    })
+  
+    return canvas
+  },
+});
+
+// Expose the global canvas
+$global.screencanvas = $global.screencanvas || new CanvasProxy();
+// NOTE: this is a hack operation
+// let canvas = new window.Canvas()
+// console.error(canvas instanceof window.Canvas)  => false
+export default CanvasProxy;