Monday, September 26, 2016

Conditional Visibility in View Templates

Conditional visibility on data fields and categories allows hiding or showing page elements based on field values. View templates give the ability to define custom presentations. When a custom template is defined for the view, the client library is not able to determine which page elements should be displayed or hidden based on the conditional visibility expressions. As such, the creator of view templates must mark up the template in order to bind these expressions with the correct elements.

When the template has been correctly defined, data fields, categories, and even custom page elements will be able to displayed or hidden depending on field values. For example, a large label is displayed in the sample below when the order has been shipped past the required date.

Warning displayed in New Order form conditionally.

Let’s use the create form for Orders in the Northwind sample database.

Arranging Data Fields into Categories

First, let’s rearrange the data fields into multiple categories, in order to control visibility of each category, instead of each individual data field. The user will only be able to enter shipping information if a shipped date is assigned.

Start the Project Designer. In the Project Explorer, switch to the Controllers tab. Right-click on “Orders / createForm1” view node, and press New Category.

Creating a new category for "createForm1" view of Orders controller.

Define the following settings:

Property Value
Header Text Ship Info
Visible When
$row.ShippedDate != null

Press OK to save the category. Next, drag data fields ShipVia, Freight, ShipName, ShipAddress, ShipCity, ShipRegion, ShipPostalCode, and ShipCountry into the new category.

Dragging shipping fields onto the second category in Orders.     Data fields have been separated into two categories in "createForm1" view of Orders controller.

Adding Data Field Visibility

Users should not be able to set the shipped date until the order date has been set. Let’s add a data field conditional visibility expression to ShippedDate data field.

Double-click on “Orders / Views / createForm1 / c1 – New Orders / ShippedDate” data field node.

Selecting ShippedDate data field in Orders controller.

Make the following change:

Property Value
Visible When
$row.OrderDate != null

Press OK to save the data field.

Adding the View Template

Let’s add a custom view template for editForm1 of Orders controller.

On the toolbar, press Develop to open the project in Visual Studio. In the Solution Explorer, right-click on the “WebSite” node and press “Add / New Folder”.

Adding a new folder to the project

Give this new folder the name “Views”. Next, right-click on the folder and press “Add / HTML Page”.

Adding a new HTML page to the Views folder.

Give this page the name “Orders.createForm1.html”. Replace the contents of the file with the following:

<div data-container="collapsible" data-header-text="New Order">
    <div data-container="row">
        <div data-control="description">Enter new order information below.</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="CustomerID">CustomerID</div>
        <div data-control="field" data-field="CustomerID">CustomerID</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="EmployeeID">EmployeeID</div>
        <div data-control="field" data-field="EmployeeID">EmployeeID</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="OrderDate">OrderDate</div>
        <div data-control="field" data-field="OrderDate">OrderDate</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="RequiredDate">RequiredDate</div>
        <div data-control="field" data-field="RequiredDate">RequiredDate</div>
    </div>
    <div data-container="row" data-visibility="f:ShippedDate">
        <div data-control="label" data-field="ShippedDate">ShippedDate</div>
        <div data-control="field" data-field="ShippedDate">ShippedDate</div>
    </div>
    <div data-container="row" data-visible-when="$row.RequiredDate < $row.ShippedDate">
        <h3 style="color:red">WARNING: THIS ORDER HAS BEEN SHIPPED LATE</h3>
    </div>
</div>
<div data-container="collapsible" data-header-text="Ship Info" data-visibility="c:c2">
    <div data-container="row">
        <div data-control="description">Enter shipping information below.</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="ShipVia">ShipVia</div>
        <div data-control="field" data-field="ShipVia">ShipVia</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="Freight">Freight</div>
        <div data-control="field" data-field="Freight">Freight</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="ShipName">ShipName</div>
        <div data-control="field" data-field="ShipName">ShipName</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="ShipAddress">ShipAddress</div>
        <div data-control="field" data-field="ShipAddress">ShipAddress</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="ShipCity">ShipCity</div>
        <div data-control="field" data-field="ShipCity">ShipCity</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="ShipRegion">ShipRegion</div>
        <div data-control="field" data-field="ShipRegion">ShipRegion</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="ShipPostalCode">ShipPostalCode</div>
        <div data-control="field" data-field="ShipPostalCode">ShipPostalCode</div>
    </div>
    <div data-container="row">
        <div data-control="label" data-field="ShipCountry">ShipCountry</div>
        <div data-control="field" data-field="ShipCountry">ShipCountry</div>
    </div>
</div>

Notice that there are three highlighted pieces in the sample above.

The yellow highlight shows how to apply data field-level visibility to an element by using the attribute “data-visibility”, and setting the value to “f:” followed by the name of the field. This will inherit the visibility from the field “ShippedDate”.

The green highlight shows how to apply category-level visibility to an element. Use the attribute “data-visibility”, and set the value to “c:” followed by the category ID. The example will inherit visibility from the category “c2”.

The orange highlight shows how to use custom JavaScript expressions to set visibility. Use the attribute “data-visible-when”, and set the value to your JavaScript visibility expression.

Switch back to the browser, navigate to the Orders page, and create a new order. Notice that the OrderDate data field, custom header, and shipping category are hidden.

When Order Date is not set, ShippedDate and ship info are hidden.

Enter a value for Order Date. Notice that the Shipped Date data field will appear.

The ShippedDate data field appears when OrderDate is set.

Enter a value for Shipped Date. The Ship Info category will appear.

Ship Info category appears when Shipped Date is set.

If the Shipped Date is after the Required Date, the warning text will appear.

A warning appears when the Shipped Date is after the Required Date.

Friday, September 23, 2016

Calculating Driving Distance Between Points

In businesses that require a lot of driving and tracking packages, it is invaluable to estimate a driving distance between two different addresses or sets of latitude/longitude. Starting in release 8.5.11.0, C# and Visual Basic business rules now have access to the CalculateDistance() method. This method will query the Google Distance Matrix API to estimate driving distance.

The results from the CalculateDistance() business rule method displayed in a messsage.

It is required to obtain and add a Maps API Identifier to your project in order to use this feature.

Please make sure to follow Google Maps APIs Terms Of Service. Of note is section 10.5.d, which restricts long-term storage of Content.

Let’s add a custom action to the Employees page that, when pressed, will display how far the employee lives from the main office using a code business rule.

First, we need to add an action that will be accessible to the user in order to trigger the code.

Start the Project Designer. In the Project Explorer, switch to the Controllers tab. Right-click on “Employees / Actions / ag1 (Grid)” node, and press New Action.

Adding an action to grid scope of Employees controller.

Enter the following settings:

Property Value
Command Name Custom
Command Argument DistanceFromHQ
Header Text Distance From HQ
When Key Selected Yes

Press OK to save. Next, let’s create a business rule that will be triggered when the user presses the action. Right-click on “Employees / Business Rules”, and press New Business Rule.

Adding a business rule to Employees controller.

Enter the following properties:

Property Value
Type C# / Visual Basic
Command Name Custom
Command Argument DistanceFromHQ
Phase Execute

Press OK to save the business rule. On the toolbar, press Browse to generate the application and create the rule file.

When generation is complete, press “Edit Rule” on the action bar to open the file in Visual Studio.

Editing the rule in Visual Studio.

Replace the contents with the following:

C#:

using System.Data;
using MyCompany.Data;
using MyCompany.Models;

namespace MyCompany.Rules
{
    public partial class EmployeesBusinessRules : MyCompany.Data.BusinessRules
    {
        
        /// <summary>
        /// This method will execute in any view for an action
        /// with a command name that matches "Custom" 
        /// and argument that matches "DistanceFromHQ".
        /// </summary>
        [Rule("r100")]
        public void r100Implementation(EmployeesModel instance)
        {
            // combine address pieces with ","
            string sourceAddress = string.Join(",", instance.Address, instance.City,
                instance.Region, instance.PostalCode, instance.Country);
            string destinationAddress = "1 Microsoft Way,Redmond,Washington";

            // get distance and calculate miles
            decimal meters = CalculateDistance(sourceAddress, destinationAddress);
            decimal miles = meters * 0.00062137m;

            // show result
            if (meters == 0)
                Result.ShowAlert("No path found.");
            else
                Result.ShowAlert("Distance from HQ is " + meters 
                    + " meters, or " + miles + " miles");
        }
    }
}

Visual Basic:

Imports MyCompany.Data
Imports MyCompany.Models

Namespace MyCompany.Rules
    
    Partial Public Class EmployeesBusinessRules
        Inherits MyCompany.Data.BusinessRules

        ''' <summary>
        ''' This method will execute in any view for an action
        ''' with a command name that matches "Custom" 
        ''' and argument that matches "DistanceFromHQ".
        ''' </summary>
        <Rule("r100")>
        Public Sub r100Implementation(ByVal instance As EmployeesModel)
            ' combine address pieces with ","
            Dim sourceAddress = String.Join(",", instance.Address, instance.City,
                    instance.Region, instance.PostalCode, instance.Country)
            Dim destinationAddress = "1 Microsoft Way,Redmond,Washington"

            ' get distance and calculate miles
            Dim meters = CalculateDistance(sourceAddress, destinationAddress)
            Dim miles = meters * 0.00062137D

            ' show result
            If (meters = 0) Then
                Result.ShowAlert("No path found.")
            Else
                Result.ShowAlert("Distance from HQ is " & meters &
                                 " meters, or " & miles & " miles")
            End If
        End Sub
    End Class
End Namespace

Switch back to the web browser, and press the three dot menu button next to any row to reveal the grid action menu.

Activating the grid scope menu for a row in Touch UI.

Press “Distance From HQ” action, and a message box will display the distance.

The results from the CalculateDistance() business rule method displayed in a messsage.

Note that it is also possible to pass a latitude and longitude by separating the values with a comma, such as in the following example:

CalculateDistance(instance.Latitude + "," + instance.Longitude, destinationAddress)

Thursday, September 22, 2016

Geocoding

Geocoding is the process of capturing an address and converting it to exact latitude and longitude coordinates. Starting with release 8.5.11.0, apps generated with Code On Time now support automatic geocoding of address fields with the proper tags, as well as a Geocode() method available in C# or Visual Basic business rules.

Example of result from Geocode method.

Please make sure to follow Google Maps APIs Terms Of Service. Of note is section 10.5.d, which restricts long-term storage of Content.

Both methods below require addition of a Maps API Identifier. The following examples will use a modified version of the Employees table from the Northwind sample project. Use the following script to add the required columns before creating the project.

ALTER TABLE Employees
ADD Latitude decimal(9, 6) NULL,
    Longitude decimal(9, 6) NULL

If using an existing project, make sure to refresh the application after executing the script. Then, open the model for Employees and check the checkbox next to the three new fields to include them in the Employees controller.

Geocoding with Tags

The easiest way to geocode a set of address fields is to tag the source and destination data fields in the view. If the correct fields are tagged, the values will be geocoded when the user saves a new record or updates an existing record. When updating an existing record, the geocode request will only be sent if at least one of the source fields has been modified, in order to avoid extraneous API requests.

Let’s add the relevant tags to start geocoding employees.

Start the Project Designer. In the Project Explorer, double-click on “Employees / container1 / view1 (Employees, grid1) / createForm1 / c1 – New Employees / Address” data field node.

Selecting the Address data field of createForm1 view of Employees controller.

Make the following change:

Property Value
Tags geocode-address

Press OK to save the data field. Use the above procedure to make the changes below:

Data Field Tag
City geocode-city
Region geocode-region
PostalCode geocode-zip
Country geocode-country
Latitude geocode-latitude
Longitude geocode-longitude

On the toolbar, press Browse. When the application opens in the default browser, create a new employee.

Entering a new employee.

Upon pressing Save, the geocode request will be sent. If a result is returned, the new employee record will have updated Latitude and Longitude fields.

The Latitude and Longitude fields have been updated.

Geocoding in C#/Visual Basic Business Rules

The tag method explained in the previous section is convenient for automatic update of Latitude and Longitude fields. However, if the latitude and longitude need to be used in a calculation, the Geocode() business rule method can be used. Let’s add a business rule that utilizes this method to geocode the employee’s address and show an alert with the resulting latitude and longitude.

In the Project Explorer, switch to the Controllers tab. Right-click on “Employees / Actions / ag4 (ActionBar) – Edit/Delete” and press New Action.

Adding a new action to Employees controller.

Specify the following properties and press OK to save the new action.

Property Value
Command Name Custom
Command Argument ShowLatLong
Header Text Show Lat/Long
When Key Selected Yes

Next, right-click on “Employees / Business Rules” node, and press New Business Rule.

Adding a new business rule to Employees controller.

Configure the rule as following:

Property Value
Type C# / Visual Basic
Command Name Custom
Command Argument ShowLatLong
Phase Execute

Press OK to save the new business rule. Then, press Browse on the toolbar to generate the application, as well as create the relevant business rule file.

When complete, press “Edit Rule” on the action bar to open the file in Visual Studio.

Editing the rule in Visual Studio.

Replace the contents of the file with the following:

C#:

using MyCompany.Data;
using MyCompany.Models;

namespace MyCompany.Rules
{
    public partial class EmployeesBusinessRules : MyCompany.Data.BusinessRules
    {
        
        /// <summary>
        /// This method will execute in any view for an action
        /// with a command name that matches "Custom" and argument that matches "ShowLatLong".
        /// </summary>
        [Rule("r100")]
        public void r100Implementation(EmployeesModel instance)
        {

            decimal latitude;
            decimal longitude;

            // join address parts with "," separator
            string address = string.Join(",", instance.Address, instance.City, 
                instance.Region, instance.PostalCode, instance.Country);

            if (Geocode(address, out latitude, out longitude))
            {
                Result.ShowAlert("Latitude: " + latitude + ", Longitude: " + longitude);
            }
            else
            {
                Result.ShowAlert("Geocode failed to resolve address.");
            }
        }
    }
}

Visual Basic:

Imports MyCompany.Data
Imports MyCompany.Models

Namespace MyCompany.Rules
    
    Partial Public Class EmployeesBusinessRules
        Inherits MyCompany.Data.BusinessRules
        
        ''' <summary>
        ''' This method will execute in any view for an action
        ''' with a command name that matches "Custom" and argument that matches "ShowLatLong".
        ''' </summary>
        <Rule("r100")>  _
        Public Sub r100Implementation(ByVal instance As EmployeesModel)
            Dim latitude As Decimal
            Dim longitude As Decimal

            ' join address parts with "," separator
            Dim address = String.Join(",", instance.Address, instance.City,
                            instance.Region, instance.PostalCode, instance.Country)

            If (Geocode(address, latitude, longitude)) Then
                Result.ShowAlert("Latitude: " & latitude & ", Longitude: " & longitude)
            Else
                Result.ShowAlert("Geocode failed to resolve address.")
            End If
        End Sub
    End Class
End Namespace

Switch back to the application running in your default browser, and navigate to the Employees page. Ctrl+click on a row to highlight the row. On the toolbar, press  “Show Lat/Long”.

Activating the "Show Lat/Long" custom action.

A message box will be displayed with the employee’s latitude and longitude.

The popup shows the returned latitude and longitude.

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