[FIX] web: reimplement custom widgets in basic views

With the new views, we lost a (almost unused and undocumented) feature:
the ability to instantiate custom widgets in a form view, not linked to
a particular field.  For example:

<widget type="weekly_timesheet" attrs="{'readonly': [['state', 'not in', ['new', 'draft']]]}"/>

We reintroduce this feature in this commit, with a nice twist: it also
works for the list view and the kanban view.

2 files changed, 66 insertions, 0 deletions

diff --git a/addons/web/static/src/js/views/basic/basic_renderer.js b/addons/web/static/src/js/views/basic/basic_renderer.js
index 0e26e2fa19f..ee6e685c3d4 100644
--- a/addons/web/static/src/js/views/basic/basic_renderer.js
+++ b/addons/web/static/src/js/views/basic/basic_renderer.js
@@ -11,6 +11,7 @@ var AbstractRenderer = require('web.AbstractRenderer');
 var config = require('web.config');
 var core = require('web.core');
 var dom = require('web.dom');
+var widgetRegistry = require('web.widget_registry');
 
 var qweb = core.qweb;
 
@@ -332,6 +333,19 @@ var BasicRenderer = AbstractRenderer.extend({
         return _.findWhere(this.allModifiersData, {node: node});
     },
     /**
+     * @private
+     * @param {jQueryElement} $el
+     * @param {Object} node
+     */
+    _handleAttributes: function ($el, node) {
+        if (node.attrs.class) {
+            $el.addClass(node.attrs.class);
+        }
+        if (node.attrs.style) {
+            $el.attr('style', node.attrs.style);
+        }
+    },
+    /**
      * Used by list and kanban renderers to determine whether or not to display
      * the no content helper (if there is no data in the state to display)
      *
@@ -541,6 +555,31 @@ var BasicRenderer = AbstractRenderer.extend({
         return $.when();
     },
     /**
+     * Instantiate custom widgets
+     *
+     * @private
+     * @param {Object} record
+     * @param {Object} node
+     * @returns {jQueryElement}
+     */
+    _renderWidget: function (record, node) {
+        var Widget = widgetRegistry.get(node.attrs.name);
+        var widget = new Widget(this, record);
+
+        // Prepare widget rendering and save the related deferred
+        var def = widget.__widgetRenderAndInsert(function () {});
+        if (def.state() === 'pending') {
+            this.defs.push(def);
+        }
+
+        // handle other attributes/modifiers
+        this._handleAttributes(widget.$el, node);
+        this._registerModifiers(node, record, widget);
+        widget.$el.addClass('o_widget');
+        return widget.$el;
+    },
+
+    /**
      * Rerenders a given widget and make sure the associated data which
      * referenced the old one is updated.
      *
diff --git a/addons/web/static/src/js/views/basic/widget_registry.js b/addons/web/static/src/js/views/basic/widget_registry.js
new file mode 100644
index 00000000000..470127bd12e
--- /dev/null
+++ b/addons/web/static/src/js/views/basic/widget_registry.js
@@ -0,0 +1,27 @@
+odoo.define('web.widget_registry', function (require) {
+    "use strict";
+
+    // This registry is supposed to contain all custom widgets that will be
+    // available in the basic views, with the tag <widget/>.  There are
+    // currently no such widget in the web client, but the functionality is
+    // certainly useful to be able to cleanly add custom behaviour in basic
+    // views (and most notably, the form view)
+    //
+    // The way custom widgets work is that they register themselves to this
+    // registry:
+    //
+    // widgetRegistry.add('some_name', MyWidget);
+    //
+    // Then, they are available with the <widget/> tag (in the arch):
+    //
+    // <widget name="some_name"/>
+    //
+    // Widgets will be then properly instantiated, rendered and destroyed at the
+    // appropriate time, with the current state in second argument.
+    //
+    // For more examples, look at the tests (grep '<widget' in the test folder)
+
+    var Registry = require('web.Registry');
+
+    return new Registry();
+});