Share Extension Part Three

[aerych]

Refs #91

This PR is part three of a four part series adding Share Extension support for sharing images to Newspack. In this PR we do the following:

• Reorganizes more code into the NewspackFramework to share between the extension and main app without duplication. In this case, ColorStudio and associated classes.
• Introduces a custom UI for the share extension.
• Wrangles shared items, and persists shared items to group storage on save. NSItemProvider wrangling is courtesy of code borrowed from WPiOS that has been slightly modified for Newspack.

This is another PR where a large portion of the changes are boiler plate, or due to incorporating existing production code from another app. New changes that need a keen eye are in:

• FileManager+Helpers.swift (improves file suffix handling)
• SharedMediaViewController.swift
• StorySelectorViewController.swift
• ShareAppearance.swift

The following files are slightly modified from their WPiOS counterparts, mostly to remove code that is not relevant to Newspack at this time. A passing glance wouldn't hurt but willing to trust the previous implementation.

• ShareExtractor.swift
• UIImage_ShareExtractor.swift
• NSExtensionContext+ShareExtractor.swift

To test:

Scenario 1: Logged out

Prep: Be logged out of Newspack. Launch the share extension with the Photos app.

• [x] Confirm a prompt appears that sharing isn't possible, and asks you to log in to Newspack before trying again.
• [x] Confirm clicking the prompt's OK button dismisses the share extension and you're returned to the Photos share screen.

Scenario 2: Logged in

Prep: Be logged in to Newspack with several stories. Launch the share extension with the Photos app.

• [x] Confirm you do not see the warning prompt.
• [x] Confirm the UI looks good in portrait and landscape orientation, and in dark and light modes.
• [x] Confirm you see the photos you selected as thumbnails.
• [x] Confirm the selected story in the share extension is the currently selected story in the main app.
• [x] Tap the story cell and use the following screen to change the story that will be shared to.
• [x] Confirm tapping the cancel button dismisses the share extension and you're returned to the Photos share screen.
• [x] Confirm tapping the save button dismisses the share extension and you're returned to the Photos app (exit all the way out of sharing).

Scenario 3: Confirm cast shadows

• [x] Launch the main app with the debugger. Observe what is logged to the console. Confirm you see the total items shared logged as shadow assets.

Scenario 4:

• [x] Launch the share extension on the iPad. Confirm it appears as a large modal form sheet and the layout and style looks good in portrait and landscape orientations, and light and dark mode.

Example Screens:

[aerych]

a potential good enhancement would be to make the "Story Picker" ViewController highlight the currently selected Story

Excellent idea.

[peril-automattic[bot]]

You can trigger an installable build for these changes by visiting CircleCI here.

[aerych]

Thanks @jleandroperez ! Changes made. One last quick peek for paranoia sake?

Screen shot showing the selected cell: It's a little different from the main app, but the main app is probably going to change too so this is a good placeholder.

[aerych]

Thank you @jleandroperez !!