Only pre-pop fields that exist in the result #219

Author: chrisala

grails-app/assets/javascripts/forms-knockout-bindings.js

@@ -1207,16 +1207,23 @@
                             if (!target) {
                                 throw "Unable to locate target for pre-population: "+target;
                             }
-                            if (_.isFunction(target.loadData)) {
-                                target.loadData(data);
-                            } else if (_.isFunction(target.load)) {
-                                target.load(data);
-                            } else if (ko.isObservable(target)) {
-                                target(data);
-                            } else {
-                                console.log("Warning: target for pre-populate is invalid");
+                            target = target.data || target;
+                            for (var prop in data) {
+                                if (target.hasOwnProperty(prop)) {
+                                    var propTarget = target[prop];
+                                    if (_.isFunction(propTarget.loadData)) {
+                                        propTarget.loadData(data[prop]);
+                                    } else if (_.isFunction(propTarget.load)) {
+                                        propTarget.load(data[prop]);
+                                    } else if (ko.isObservable(propTarget)) {
+                                        propTarget(data[prop]);
+                                    } else {
+                                        console.log("Warning: target for pre-populate is invalid");
+                                    }
+                                }
                             }
 
+
                         }); // This is a computed rather than a pureComputed as it has a side effect.
                     });
                 }

grails-app/conf/example_models/behavioursExample.json

@@ -45,22 +45,13 @@
                   "name": "param",
                   "type": "computed",
                   "expression": "item5"
-                },
-                {
-                  "name": "item5",
-                  "type": "computed",
-                  "expression": "item5"
                 }
               ]
             },
             "mapping": [
               {
                 "source-path": "param",
                 "target": "item6"
-              },
-              {
-                "source-path": "item5",
-                "target": "item5"
               }
             ],
             "target": "$data"
@@ -119,7 +110,7 @@
           "items": [
             {
               "type": "literal",
-              "source": "Note for this example, data entered into item5 will trigger a pre-pop call and be mapped back to item5 and item6.  Note that the target of the pre-pop is $data which is the current binding context (or the root object in this case).  A current limitation is the load method is used, which means if the pre-pop result does not contain keys for all data in the target object, the data for missing fields will be set to undefined.   A planned enhancement is to only replace data where keys in the pre-pop data exist."
+              "source": "Note for this example, data entered into item5 will trigger a pre-pop call and be mapped back to item6.  Note that the target of the pre-pop is $data which is the current binding context (or the root object in this case).  A current limitation is the load method is used for all keys in the returned data, which means if the data is nested and the pre-pop result does not contain keys for all nested data in the nested target object, the data for missing fields will be set to undefined."
             }
           ]
         }