Office 365: How to Create a Task Pane App For Excel Online Using Napa Tool

First you need to sign up for an Office 365 Developer Site.

Be sure you have access to an Office 365 Developer Site. Here are three ways to get one:

• Are you an MSDN subscriber? Visual Studio Ultimate and Visual Studio Premium with MSDN subscribers receive an Office 365 Developer Subscription as a benefit. Redeem your benefit today.
  
  
• Do you have one of the following Office 365 subscription plans?
  
  
  • Office 365 Midsize Business
  • Office 365 Enterprise E1, E3, E4, or K1
  • Office 365 Education A2, A3, or A4
  • Office 365 Government G1, G3, G4, or K1
  
  If so, you can provision a Developer Site from the Office 365 admin center.
  
  
• You can either start with a free 30-day trial, or buy an Office 365 developer subscription (with one user license for either option) using one of the following links. This subscription costs $99.00 per year.

Please refer to Sign up for an Office 365 Developer Subscription and set up your tools and environment for more details.

Install “Napa” Office 365 Development Tools to your developer site

"Napa" Office 365 Development Tools is a browser-based authoring tool that makes developing apps for Office and SharePoint quick and easy. You can't use the "Napa" Office 365 Development Tools to create provider-hosted apps for SharePoint, but you can use them to create SharePoint-hosted apps.

Please refer to Install “Napa” Office 365 Development Tools to your developer site for more details.

Use the following procedure to create an app for Excel Online using Napa Tool:

1. Navigate to https://portal.office.com/.
   
   
2. Click on the Build Apps link.
   
   
   
   
3. Click on the Build an app tile.
   
   
   
   
4. Click on Add New Project.
   
   
   
   
5. Select Task pane app for Office, enter the project name and then click on the Create button.
   
   
   
   
6. The new project is created with all the files shown below.
   
   
   
   
7. Home.html contains the HTML contents that will be rendered as the UI for the app.
   
   
   
   
8. Home.js contains all the functions required for the app.
   
   

Deploy the app

1. On the left navigation, click on the Run Project button.
   
   
   
   
2. The app is installing.
   
   
   
   
   
   
3. The app is installed successfully.
   
   

Test the app

1. Click on the “Click here to launch your app in a new window” link.
   
   
2. Excel Online is opened and the app is displayed on the task pane as shown below.
   
   
   
   
3. Select a cell and then click the Get data from selection button.
   
   

Summary

Thus in this article you have seen how to create a task pane app for Excel Online using the Napa Tool.