Creating UI for File Upload. User navigation when file upload is in progress

Purpose: To have an alert if a user tries to navigate away from the file upload screen before all files have been fully uploaded. The file upload component cancels an upload if a user leaves the file upload screen, so they should have a warning message before they are allowed to leave the screen.

As a staff person
If some of the uploads are still in process, I want to be warned before navigating away from the file upload screen,
So that I do not accidentally disrupt the file upload process

Notes:

• This story is a logical addition to UIDATIMP-37.

Scenarios

1. Scenario 1
   • Given the File Upload component
   • When all files have been completely uploaded
   • Then the user should be able to navigate away from that screen without any errors or warning messages.

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[Not implemented in this story]

1. Scenario 2
   • Given the File Upload component
   • When one or more files have not yet been completely uploaded
   • Then the user should see a warning modal if they try to navigate away from the file upload screen, as shown in the attached 14-Modal - Leave page.png
     • • Header: Leave the page
       • horizontal line
       • Text: There are unfinished uploads. If you would like to complete all uploads, press the "Keep uploading" button.
       • space
       • horizontal line
       • White button on left: Close & lose partial uploads
       • Blue button on right: Keep uploading
       • Modal does not display if I switch to a different screen before finishing file upload. See attached video Scenario 2 problem
2. Scenario 3 [Can't test since I can't get the modal to display]
   • Given the warning modal
   • If the user clicks the "Close & lose partial uploads" button
   • Then the system should close the modal, cancel upload for any unfinished uploads, NOT display the icon for any cancelled uploads, and allow the user to navigate away from the file upload screen.
3. Scenario 4 [Can't test since I can't get the modal to display]
   • Given the warning modal
   • If the user clicks the "Keep uploading" button
   • Then the system should close the modal, return the user to the file upload screen, and continue uploading any incomplete uploads.

Note See the comments about the Stripes modal component on UIDATIMP-46. It doesn't accommodate placing the buttons on opposite sides of the box. Place them next to each other justified right, similar to this: