feat(ionSideMenu): add edge-drag-threshold, delegate `edgeDragThres…

…hold()`

Closes #1570

js/angular/controller/sideMenuController.js

@@ -9,6 +9,7 @@ function($scope, $attrs, $ionicSideMenuDelegate, $ionicPlatform) {
   extend(this, ionic.controllers.SideMenuController.prototype);
 
   this.$scope = $scope;
+  this.dragThreshold = 25;
 
   ionic.controllers.SideMenuController.call(this, {
     left: { width: 275 },
@@ -22,6 +23,19 @@ function($scope, $attrs, $ionicSideMenuDelegate, $ionicPlatform) {
     return $scope.dragContent;
   };
 
+  this.dragThreshold = 25;
+  this.edgeDragThreshold = function(value) {
+    if (arguments.length) {
+      if (angular.isNumber(value) && value > 0) {
+        this.dragThreshold = value;
+        this.dragOnlyEdge = true;
+      } else {
+        this.dragOnlyEdge = !!value;
+      }
+    }
+    return this.dragOnlyEdge;
+  };
+
   this.isDraggableTarget = function(e) {
     return $scope.dragContent &&
            (!e.gesture.srcEvent.defaultPrevented &&

js/angular/directive/sideMenuContent.js

@@ -12,13 +12,18 @@
  * @usage
  * ```html
  * <ion-side-menu-content
+ *   edge-drag-threshold="true"
  *   drag-content="true">
  * </ion-side-menu-content>
  * ```
  * For a complete side menu example, see the
  * {@link ionic.directive:ionSideMenus} documentation.
  *
  * @param {boolean=} drag-content Whether the content can be dragged. Default true.
+ * @param {boolean|number=} edge-drag-threshold Whether the content drag can only start if it is below a certain threshold distance from the edge of the screen.  Default false. Accepts three types of values:
+   *  - If a non-zero number is given, that many pixels is used as the maximum allowed distance from the edge that starts dragging the side menu.
+   *  - If true is given, the default number of pixels (25) is used as the maximum allowed distance.
+   *  - If false or 0 is given, the edge drag threshold is disabled, and dragging from anywhere on the content is allowed.
  *
  */
 IonicModule
@@ -37,14 +42,20 @@ function($timeout, $ionicGesture) {
 
         $element.addClass('menu-content pane');
 
-        if (angular.isDefined(attr.dragContent)) {
+        if (isDefined(attr.dragContent)) {
           $scope.$watch(attr.dragContent, function(value) {
             sideMenuCtrl.canDragContent(value);
           });
         } else {
           sideMenuCtrl.canDragContent(true);
         }
 
+        if (isDefined(attr.edgeDragThreshold)) {
+          $scope.$watch(attr.edgeDragThreshold, function(value) {
+            sideMenuCtrl.edgeDragThreshold(value);
+          });
+         }
+
         var defaultPrevented = false;
         var isDragging = false;
 
@@ -87,6 +98,7 @@ function($timeout, $ionicGesture) {
         var releaseGesture = $ionicGesture.on('release', dragReleaseFn, $element);
 
         sideMenuCtrl.setContent({
+          element: element[0],
           onDrag: function(e) {},
           endDrag: function(e) {},
           getTranslateX: function() {

js/angular/service/sideMenuDelegate.js

@@ -89,7 +89,17 @@ IonicModule
    * side menus.
    * @returns {boolean} Whether the content can be dragged to open side menus.
    */
-  'canDragContent'
+  'canDragContent',
+  /**
+   * @ngdoc method
+   * @name $ionicSideMenuDelegate#edgeDragThreshold
+   * @param {boolean|number=} value Set whether the content drag can only start if it is below a certain threshold distance from the edge of the screen. Accepts three different values:
+   *  - If a non-zero number is given, that many pixels is used as the maximum allowed distance from the edge that starts dragging the side menu.
+   *  - If true is given, the default number of pixels (25) is used as the maximum allowed distance.
+   *  - If false or 0 is given, the edge drag threshold is disabled, and dragging from anywhere on the content is allowed.
+   * @returns {boolean} Whether the drag can start only from within the edge of screen threshold.
+   */
+  'edgeDragThreshold',
   /**
    * @ngdoc method
    * @name $ionicSideMenuDelegate#$getByHandle

js/controllers/sideMenuController.js

@@ -1,7 +1,7 @@
 (function(ionic) {
 'use strict';
 
-  /**
+/**
    * The SideMenuController is a controller with a left and/or right menu that
    * can be slid out and toggled. Seen on many an app.
    *
@@ -278,10 +278,28 @@
       this._startX = null;
       this._lastX = null;
       this._offsetX = null;
+      this._firstX = null;
+      this._doDrag = false;
     },
 
     // Handle a drag event
     _handleDrag: function(e) {
+
+      //Get the start position of the drag
+      if (!this._firstX) {
+       this._firstX = e.gesture.touches[0].pageX;
+       this.content._cachedWidth = this.content.element.offsetWidth;
+      }
+
+      //Allow the drag to affect the side if:
+      // - the side menu is already opened, or
+      // - there is no edge drag threshold enabled, or
+      // - the drag is within the edge drag threshold
+      this._doDrag = this.isOpen() ||
+        !this.edgeDragThreshold() ||
+        this._firstX <= this.dragThreshold ||
+        this._firstX >= this.content._cachedWidth - this.dragThreshold;
+
       // If we don't have start coords, grab and store them
       if(!this._startX) {
         this._startX = e.gesture.touches[0].pageX;
@@ -292,7 +310,7 @@
       }
 
       // Calculate difference from the tap points
-      if(!this._isDragging && Math.abs(this._lastX - this._startX) > this.dragThresholdX) {
+      if(!this._isDragging && this._doDrag && Math.abs(this._lastX - this._startX) > this.dragThresholdX) {
         // if the difference is greater than threshold, start dragging using the current
         // point as the starting point
         this._startX = this._lastX;

test/html/sideMenu.html

@@ -13,7 +13,7 @@
 
       <ion-side-menus>
 
-        <ion-side-menu-content>
+        <ion-side-menu-content edge-drag-threshold="false">
           <header class="bar bar-header bar-positive">
             <button class="button button-icon ion-navicon" ng-click="toggleLeft()"></button>
             <h1 class="title">Slide me</h1>