update managed identity docs

Author: jjbfour

articles/azure-resource-manager/managed-applications/media/publish-managed-identity/msi-cuid.png

@@ -48,7 +48,7 @@ A Managed Application can be configured with Managed Identity through the [Creat
 
 ```json
 "outputs": {
-    "managedIdentity": "[parse('{\"Type\":\"SystemAssigned\"}')]"
+    "managedIdentity": { "Type": "SystemAssigned" }
 }
 ```
 
@@ -60,71 +60,65 @@ Below are some recommendations on when to use CreateUIDefinition for enabling Ma
 - The Managed Identity requires complex consumer input.
 - The Managed Identity is needed on creation of the Managed Application.
 
-#### SystemAssigned CreateUIDefinition
+#### Managed Identity CreateUIDefinition control
 
-A basic CreateUIDefinition that enables the SystemAssigned identity for the Managed Application.
+CreateUIDefinition supports a built-in [Managed Identity control](./microsoft-managedidentity-identityselector.md).
 
 ```json
 {
   "$schema": "https://schema.management.azure.com/schemas/0.1.2-preview/CreateUIDefinition.MultiVm.json#",
   "handler": "Microsoft.Azure.CreateUIDef",
-  "version": "0.1.2-preview",
-    "parameters": {
-        "basics": [
-            {}
-        ],
-        "steps": [
-        ],
-        "outputs": {
-            "managedIdentity": "[parse('{\"Type\":\"SystemAssigned\"}')]"
-        }
-    }
-}
-```
-
-#### UserAssigned CreateUIDefinition
-
-A basic CreateUIDefinition that takes a **user-assigned identity** resource as input and enables the UserAssigned identity for the Managed Application.
-
-```json
-{
-  "$schema": "https://schema.management.azure.com/schemas/0.1.2-preview/CreateUIDefinition.MultiVm.json#",
-  "handler": "Microsoft.Azure.CreateUIDef",
-  "version": "0.1.2-preview",
-    "parameters": {
-        "basics": [
-            {}
-        ],
-        "steps": [
-            {
-                "name": "manageIdentity",
-                "label": "Identity",
-                "subLabel": {
-                    "preValidation": "Manage Identities",
-                    "postValidation": "Done"
-                },
-                "bladeTitle": "Identity",
-                "elements": [
-                    {
-                        "name": "userAssignedText",
-                        "type": "Microsoft.Common.TextBox",
-                        "label": "User assigned managed identity",
-                        "defaultValue": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/testRG/providers/Microsoft.ManagedIdentity/userassignedidentites/myuserassignedidentity",
-                        "visible": true
-                    }
-                ]
-            }
-        ],
-        "outputs": {
-            "managedIdentity": "[parse(concat('{\"Type\":\"UserAssigned\",\"UserAssignedIdentities\":{',string(steps('manageIdentity').userAssignedText),':{}}}'))]"
-        }
+  "version": "0.0.1-preview",
+  "parameters": {
+    "basics": [],
+    "steps": [
+      {
+        "name": "applicationSettings",
+        "label": "Application Settings",
+        "subLabel": {
+          "preValidation": "Configure your application settings",
+          "postValidation": "Done"
+        },
+        "bladeTitle": "Application Settings",
+        "elements": [
+          {
+            "name": "appName",
+            "type": "Microsoft.Common.TextBox",
+            "label": "Managed application Name",
+            "toolTip": "Managed application instance name",
+            "visible": true
+          },
+          {
+            "name": "appIdentity",
+            "type": "Microsoft.ManagedIdentity.IdentitySelector",
+            "label": "Managed Identity Configuration",
+            "toolTip": {
+              "systemAssignedIdentity": "Enable system assigned identity to grant the managed application access to additional existing resources.",
+              "userAssignedIdentity": "Add user assigned identities to grant the managed application access to additional existing resources."
+            },
+            "defaultValue": {
+              "systemAssignedIdentity": "Off"
+            },
+            "options": {
+              "hideSystemAssignedIdentity": false,
+              "hideUserAssignedIdentity": false,
+              "readOnlySystemAssignedIdentity": false
+            },
+            "visible": true
+          }
+        ]
+      }
+    ],
+    "outputs": {
+      "applicationResourceName": "[steps('applicationSettings').appName]",
+      "location": "[location()]",
+      "managedIdentity": "[steps('applicationSettings').appIdentity]"
     }
+  }
 }
 ```
 
-The CreateUIDefinition.json above generates a create user experience that has a textbox for a consumer to enter the **user-assigned identity** Azure resource ID. The generated experience would look like:
-
-![Sample user-assigned identity CreateUIDefinition](./media/publish-managed-identity/user-assigned-identity.png)
+![Managed Identity CreateUIDefinition](./media/publish-managed-identity/msi-cuid.png)
 
 ### Using Azure Resource Manager templates