Liquid glass + button

[mpivchev]

Follow up from #4171
Convert the regular + button to a prominent liquid glass button for >= iOS 26

Before:

After:

[Copilot]

Pull request overview

This PR updates the floating “+” menu button styling to use the new prominent liquid glass button style on iOS 26+, while preserving the existing custom round/shadowed appearance on earlier iOS versions.

Changes:

• Switch the iOS 26+ “+” button to UIButton.Configuration.prominentGlass() and adjust the SF Symbol size.
• Centralize plus-button theming into a UIButton.setPlusButtonColor(_:) helper and update call sites to use it.
• Keep the legacy (pre–iOS 26) appearance path with corner radius + shadow, while applying color via the helper.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
iOSClient/Menu/NCContextMenuPlus.swift	Uses the shared helper to apply theming to the context-menu “+” button.
iOSClient/Main/NCMainNavigationController.swift	Creates a prominent glass configuration for iOS 26+ and introduces the shared plus-button coloring helper.
iOSClient/Files/NCFiles.swift	Updates theme and enabled/disabled state handling to apply color through the shared helper.

Comments suppressed due to low confidence (1)

iOSClient/Menu/NCContextMenuPlus.swift:441

• NCContextMenuPlus.create(session:) is not @MainActor, but this block updates menuPlusButton UI state after several awaits. Because non-main-actor async functions may resume on a background executor, these UIKit mutations can run off the main thread. Wrapping the UI updates in MainActor.run here avoids potential data races/crashes under strict concurrency.

        menuPlusButton.setPlusButtonColor(NCBrandColor.shared.getElement(account: session.account))
        menuPlusButton.alpha = 1

        // E2EE Offline disable
        menuPlusButton.isEnabled = isNetworkReachable || !isDirectoryE2EE

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[kra-mo]

Neat!

[marinofaggiana]

please before the review try:

when change the account the [+] appear so :

[marinofaggiana]

pls change.

[mpivchev]

This happened because the merge reverted my changes. Fixed now.

[mpivchev]

we control if the button is enabled in 2 places:

In NCFiles:
menuPlusButton.isEnabled = metadataFolder.isCreatable

and NCContextMenuPlus:

menuPlusButton.isEnabled = isNetworkReachable || !isDirectoryE2EE

This causes the file to reenable even if it should not.

Will fix.

Edit: #4195