Set External Context

Introduction

You can set up an external context when launching your application. This is especially helpful when starting an app from somewhere else, for example a robotic process automation (RPA) process.

Demo app - try it yourself

To try setting the external content yourself, use the demo app or follow the procedure.

Download demo app from GitHub

Preview demo app in cloud

Demo app - instructions to use

1. Run the demo app. All the expressions using the App.QueryParam function should display their default values.

2. To reset expressions to their default values, click the Next page button.

3. Copy the following syntax and append it in the app URL after the el=vb part:

   &intv=3200&guidv="81a130d2-502f-4cf1-a376-63edeb000e9f"&sv=queryparam&bv=true&dv=1000000.222&datetimev="2/1/2022 11:00:00 AM"&datetimeoffv="4/2/2007 7:23:57 PM"&listv={"data":["apps","engineering","team"]}&file={"Name":"image","FileSize":25}

4. To display an image in the document viewer, add URL="https://my-public-image-URL" in the file parameter. For example:

   file={"Name":"image","FileSize":25, URL="https://my-public-image-URL"}

5. Press Enter and watch the values being updated.

Procedure

Note:

To reference the external context using VB expressions, use the App.QueryParam() function.

Query parameters are case sensitive For example, intv and INTV are treated differently.

1. Add a Textbox control.

2. For the Text property, open the Expression editor.

3. Bind the query parameter function to the Text property by using the App.QueryParam() function:

   App.QueryParam(Of Integer)("intv", 100).ToString

   Important:

   Inside the App.QueryParam() brackets, specify the data type of the value you are passing in the URL. For example, if the value is an integer, you need to specify App.QueyParam(Of Integer).
4. Publish the app. At the initial runtime, you should see the default value specified using the App.QueyParam() function, which is 100.
5. Add query parameters after the el=vb part in the runtime URL by using the & character, then press Enter. For example, el=vb&intv=250.
   The textbox should display 250.