add layer event #53

modules/layer/Layer.js

@@ -22,7 +22,6 @@ class Layer {
     this._layerEvent = new LayerEvent()
     this._layerEvent.on(LayerEventType.ADD, this._onAdd, this)
     this._layerEvent.on(LayerEventType.REMOVE, this._onRemove, this)
-    this._state = undefined
   }
 
   get layerId() {
@@ -128,12 +127,9 @@ class Layer {
    * @private
    */
   _addOverlay(overlay) {
-    if (
-      overlay?.overlayEvent &&
-      !this._cache.hasOwnProperty(overlay.overlayId)
-    ) {
+    if (!this._cache.hasOwnProperty(overlay.overlayId)) {
       this._cache[overlay.overlayId] = overlay
-      this._delegate && overlay.overlayEvent.fire(OverlayEventType.ADD, this)
+      this._delegate && overlay.fire(OverlayEventType.ADD, this)
       if (this._state === State.CLEARED) {
         this._state = State.ADDED
       }
@@ -146,11 +142,8 @@ class Layer {
    * @private
    */
   _removeOverlay(overlay) {
-    if (
-      overlay?.overlayEvent &&
-      this._cache.hasOwnProperty(overlay.overlayId)
-    ) {
-      this._delegate && overlay.overlayEvent.fire(OverlayEventType.REMOVE, this)
+    if (this._cache.hasOwnProperty(overlay.overlayId)) {
+      this._delegate && overlay.fire(OverlayEventType.REMOVE, this)
       delete this._cache[overlay.overlayId]
     }
   }
@@ -288,6 +281,41 @@ class Layer {
    */
   setStyle(style) {}
 
+  /**
+   * Subscribe event
+   * @param type
+   * @param callback
+   * @param context
+   * @returns {Layer}
+   */
+  on(type, callback, context) {
+    this._layerEvent.on(type, callback, context || this)
+    return this
+  }
+
+  /**
+   * Unsubscribe event
+   * @param type
+   * @param callback
+   * @param context
+   * @returns {Layer}
+   */
+  off(type, callback, context) {
+    this._layerEvent.off(type, callback, context || this)
+    return this
+  }
+
+  /**
+   * Trigger subscription event
+   * @param type
+   * @param params
+   * @returns {Layer}
+   */
+  fire(type, params) {
+    this._layerEvent.fire(type, params)
+    return this
+  }
+
   /**
    * Registers Type
    * @param type

modules/overlay/Overlay.js

@@ -22,8 +22,8 @@ class Overlay {
     this._allowDrillPicking = false
     this._contextMenu = []
     this._overlayEvent = new OverlayEvent()
-    this.on(OverlayEventType.ADD, this._onAdd, this)
-    this.on(OverlayEventType.REMOVE, this._onRemove, this)
+    this._overlayEvent.on(OverlayEventType.ADD, this._onAdd, this)
+    this._overlayEvent.on(OverlayEventType.REMOVE, this._onRemove, this)
   }
 
   get overlayId() {

modules/viewer/Viewer.js

@@ -213,12 +213,10 @@ class Viewer {
    * @private
    */
   _addLayer(layer) {
-    if (layer?.layerEvent) {
-      !this._layerCache[layer.type] && (this._layerCache[layer.type] = {})
-      if (!Object(this._layerCache[layer.type]).hasOwnProperty(layer.id)) {
-        layer.layerEvent.fire(LayerEventType.ADD, this)
-        this._layerCache[layer.type][layer.id] = layer
-      }
+    !this._layerCache[layer.type] && (this._layerCache[layer.type] = {})
+    if (!Object(this._layerCache[layer.type]).hasOwnProperty(layer.id)) {
+      layer.fire(LayerEventType.ADD, this)
+      this._layerCache[layer.type][layer.id] = layer
     }
   }
 
@@ -227,11 +225,8 @@ class Viewer {
    * @private
    */
   _removeLayer(layer) {
-    if (
-      layer?.layerEvent &&
-      Object(this._layerCache[layer.type]).hasOwnProperty(layer.id)
-    ) {
-      layer.layerEvent.fire(LayerEventType.REMOVE, this)
+    if (Object(this._layerCache[layer.type]).hasOwnProperty(layer.id)) {
+      layer.fire(LayerEventType.REMOVE, this)
       delete this._layerCache[layer.type][layer.id]
     }
   }
@@ -444,10 +439,7 @@ class Viewer {
    * @returns {boolean}
    */
   hasLayer(layer) {
-    return (
-      layer?.layerEvent &&
-      Object(this._layerCache[layer.type]).hasOwnProperty(layer.id)
-    )
+    return Object(this._layerCache[layer.type]).hasOwnProperty(layer.id)
   }
 
   /**