Add js default values for widget-image and widget-link

Author: SylvainCorlay

ipywidgets/static/widgets/js/widget_image.js

@@ -7,9 +7,21 @@ if (typeof define !== 'function') { var define = require('./requirejs-shim')(mod
 define([
     "./widget",
     "jquery",
-], function(widget, $) {
-    
-    var ImageView = widget.DOMWidgetView.extend({  
+    "underscore",
+], function(widget, $, _) {
+
+    var ImageModel = widget.DOMWidgetModel.extend({
+        defaults: _.extend({}, widget.DOMWidgetModel.prototype.defaults, {
+            _model_name: "ImageModel",
+            _view_name: "ImageView",
+            format: "png",
+            width: "",
+            height: "",
+            _b64value: ""
+        }),
+    });
+
+    var ImageView = widget.DOMWidgetView.extend({
         render : function() {
             /**
              * Called when view is rendered.
@@ -18,24 +30,24 @@ define([
                 .addClass("ipy-widget widget-image"));
             this.update(); // Set defaults.
         },
-        
+
         update : function() {
             /**
              * Update the contents of this view
              *
-             * Called when the model is changed.  The model may have been 
+             * Called when the model is changed.  The model may have been
              * changed by another view or by a state update from the back-end.
              */
             var image_src = 'data:image/' + this.model.get('format') + ';base64,' + this.model.get('_b64value');
             this.$el.attr('src', image_src);
-            
+
             var width = this.model.get('width');
             if (width !== undefined && width.length > 0) {
                 this.$el.attr('width', width);
             } else {
                 this.$el.removeAttr('width');
             }
-            
+
             var height = this.model.get('height');
             if (height !== undefined && height.length > 0) {
                 this.$el.attr('height', height);
@@ -47,6 +59,7 @@ define([
     });
 
     return {
-        'ImageView': ImageView,
+        ImageView: ImageView,
+        ImageModel: ImageModel,
     };
 });

ipywidgets/static/widgets/js/widget_link.js

@@ -12,6 +12,11 @@ define([
 
     var BaseLinkModel = widget.WidgetModel.extend({
 
+        defaults: _.extend({}, widget.WidgetModel.prototype.defaults, {
+            target: undefined,
+            source: undefined,
+        }),
+
         update_value: function(source, target) {
             if (this.updating) {
                 return;
@@ -50,6 +55,10 @@ define([
 
     var LinkModel = BaseLinkModel.extend({
 
+        defaults: _.extend({}, BaseLinkModel.prototype.defaults, {
+            _model_name, "LinkModel"
+        }),
+
         initialize: function() {
             this.on("change", this.update_bindings, this);
         },
@@ -72,11 +81,14 @@ define([
                 this.listenToOnce(this.target[0], "destroy", this.cleanup, this);
             }
         },
-
     });
 
     var DirectionalLinkModel = BaseLinkModel.extend({
 
+        defaults: _.extend({}, BaseLinkModel.prototype.defaults, {
+            _model_name, "DirectionalLinkModel"
+        }),
+
         initialize: function() {
             this.on("change", this.update_bindings, this);
         },
@@ -100,7 +112,7 @@ define([
     });
 
     return {
-        "LinkModel": LinkModel,
-        "DirectionalLinkModel": DirectionalLinkModel,
+        LinkModel: LinkModel,
+        DirectionalLinkModel: DirectionalLinkModel,
     }
 });

ipywidgets/widgets/widget_image.py

@@ -17,11 +17,13 @@
 class Image(DOMWidget):
     """Displays an image as a widget.
 
-    The `value` of this widget accepts a byte string.  The byte string is the raw
-    image data that you want the browser to display.  You can explicitly define
-    the format of the byte string using the `format` trait (which defaults to
-    "png")."""
+    The `value` of this widget accepts a byte string.  The byte string is the
+    raw image data that you want the browser to display.  You can explicitly
+    define the format of the byte string using the `format` trait (which
+    defaults to "png").
+    """
     _view_name = Unicode('ImageView', sync=True)
+    _model_name = Unicode('ImageModel', sync=True)
 
     # Define the custom state properties to sync with the front-end
     format = Unicode('png', sync=True)