refactor(Focus): Use handleEvent instead of arrow functions

src/focus.js

@@ -1,79 +1,78 @@
-import {customAttribute} from 'aurelia-templating';
-import {bindingMode} from 'aurelia-binding';
-import {inject} from 'aurelia-dependency-injection';
-import {TaskQueue} from 'aurelia-task-queue';
-import {DOM} from 'aurelia-pal';
-
-/**
-* CustomAttribute that binds provided DOM element's focus attribute with a property on the viewmodel.
-*/
-@customAttribute('focus', bindingMode.twoWay)
-@inject(DOM.Element, TaskQueue)
-export class Focus {
-  /**
-  * Creates an instance of Focus.
-  * @paramelement Target element on where attribute is placed on.
-  * @param taskQueue The TaskQueue instance.
-  */
-  constructor(element, taskQueue) {
-    this.element = element;
-    this.taskQueue = taskQueue;
-    this.isAttached = false;
-    this.needsApply = false;
-
-    this.focusListener = e => {
-      this.value = true;
-    };
-    this.blurListener = e => {
-      if (DOM.activeElement !== this.element) {
-        this.value = false;
-      }
-    };
-  }
-
-  /**
-  * Invoked everytime the bound value changes.
-  * @param newValue The new value.
-  */
-  valueChanged(newValue) {
-    if (this.isAttached) {
-      this._apply();
-    } else {
-      this.needsApply = true;
-    }
-  }
-
-  _apply() {
-    if (this.value) {
-      this.taskQueue.queueMicroTask(() => {
-        if (this.value) {
-          this.element.focus();
-        }
-      });
-    } else {
-      this.element.blur();
-    }
-  }
-
-  /**
-  * Invoked when the attribute is attached to the DOM.
-  */
-  attached() {
-    this.isAttached = true;
-    if (this.needsApply) {
-      this.needsApply = false;
-      this._apply();
-    }
-    this.element.addEventListener('focus', this.focusListener);
-    this.element.addEventListener('blur', this.blurListener);
-  }
-
-  /**
-  * Invoked when the attribute is detached from the DOM.
-  */
-  detached() {
-    this.isAttached = false;
-    this.element.removeEventListener('focus', this.focusListener);
-    this.element.removeEventListener('blur', this.blurListener);
-  }
-}
+import {customAttribute} from 'aurelia-templating';
+import {bindingMode} from 'aurelia-binding';
+import {inject} from 'aurelia-dependency-injection';
+import {TaskQueue} from 'aurelia-task-queue';
+import {DOM} from 'aurelia-pal';
+
+/**
+* CustomAttribute that binds provided DOM element's focus attribute with a property on the viewmodel.
+*/
+@customAttribute('focus', bindingMode.twoWay)
+@inject(DOM.Element, TaskQueue)
+export class Focus {
+  /**
+  * Creates an instance of Focus.
+  * @paramelement Target element on where attribute is placed on.
+  * @param taskQueue The TaskQueue instance.
+  */
+  constructor(element, taskQueue) {
+    this.element = element;
+    this.taskQueue = taskQueue;
+    this.isAttached = false;
+    this.needsApply = false;
+  }
+
+  /**
+  * Invoked everytime the bound value changes.
+  * @param newValue The new value.
+  */
+  valueChanged(newValue) {
+    if (this.isAttached) {
+      this._apply();
+    } else {
+      this.needsApply = true;
+    }
+  }
+
+  _apply() {
+    if (this.value) {
+      this.taskQueue.queueMicroTask(() => {
+        if (this.value) {
+          this.element.focus();
+        }
+      });
+    } else {
+      this.element.blur();
+    }
+  }
+
+  /**
+  * Invoked when the attribute is attached to the DOM.
+  */
+  attached() {
+    this.isAttached = true;
+    if (this.needsApply) {
+      this.needsApply = false;
+      this._apply();
+    }
+    this.element.addEventListener('focus', this);
+    this.element.addEventListener('blur', this);
+  }
+
+  /**
+  * Invoked when the attribute is detached from the DOM.
+  */
+  detached() {
+    this.isAttached = false;
+    this.element.removeEventListener('focus', this);
+    this.element.removeEventListener('blur', this);
+  }
+
+  handleEvent(e) {
+    if (e.type === 'focus') {
+      this.value = true;
+    } else if (DOM.activeElement !== this.element) {
+      this.value = false;
+    }
+  }
+}