[Bug]: (share_plus) iOS drops the subject when sharing a uri

[sanderpensa]

Platform

iOS 15

Plugin

share_plus

Version

13.3.0

Flutter SDK

3.44.9

Steps to reproduce

1. On an iOS device, share a uri with a subject (see the code sample).
2. Pick Mail in the share sheet.
3. The Mail compose view opens with an empty subject line.

On Android the same call fills the subject, because Share.kt puts it in EXTRA_SUBJECT for a uri too. ShareParams.subject is documented as "Supported platforms: All".

This is not a duplicate of #3968, #347 or #691. Those are about the text path and Gmail. This is the uri path, where the subject never reaches the share sheet at all.

Cause

The uri branch of FPPSharePlusPlugin.m never reads the subject:

• The subject is read into shareTitle (L294-L297), but only shareText: and shareFiles: receive it.
• shareUri: calls share:withSubject:nil (L460-L472).
• share:withSubject: only skips NSNull, so it sets the controller's subject to nil (L409-L411). The comment on that block says it is there to force the subject "when sharing a raw url or files", which is exactly the case that gets nil.

Suggested fix

Pass shareTitle into shareUri: and forward it to share:withSubject: instead of nil, as shareText: and shareFiles: already do. The item stays an NSURL, so the rich link preview is unaffected.

Code Sample

await SharePlus.instance.share(
  ShareParams(
    uri: Uri.parse('https://flutter.dev'),
    subject: 'Subject for Mail',
  ),
);

Logs

No error or exception. The share sheet and Mail open normally, only the subject is empty.

Flutter Doctor

[✓] Flutter (Channel stable, 3.44.9, on macOS 26.6.2 25G83 darwin-arm64, locale en-EE) [431ms]
    • Flutter version 3.44.9 on channel stable at /Users/**/.local/share/mise/http-tarballs/e5c14d6b5e917a8578327d2564ab78ece83cd685c74c29572ddaf7655f42205d
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 6b182d2c75 (8 weeks ago), 2026-08-05 10:04:07 -0700
    • Engine revision 5a2a6a42cc
    • Dart version 3.12.2
    • DevTools version 2.57.0
    • Feature flags: enable-web, enable-linux-desktop, enable-macos-desktop, enable-windows-desktop, enable-android, enable-ios, cli-animations, enable-native-assets, no-enable-swift-package-manager,
      omit-legacy-version-file, enable-lldb-debugging, no-enable-uiscene-migration

[✓] Android toolchain - develop for Android devices (Android SDK version 37.0.0) [1,412ms]
    • Android SDK at /Users/**/Library/Android/sdk
    • Emulator version 36.1.9.0 (build_id 13823996) (CL:N/A)
    • Platform android-37.0, build-tools 37.0.0
    • ANDROID_HOME = /Users/**/Library/Android/sdk
    • Java binary at: /Applications/Android Studio.app/Contents/jbr/Contents/Home/bin/java
      This is the JDK bundled with the latest Android Studio installation on this machine.
      To manually set the JDK path, use: `flutter config --jdk-dir="path/to/jdk"`.
    • Java version OpenJDK Runtime Environment (build 21.0.9+-14787801-b1163.94)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 26.6) [1,046ms]
    • Xcode at /Applications/Xcode-26.6.0.app/Contents/Developer
    • Build 17F113
    • CocoaPods version 1.17.0

[✓] Chrome - develop for the web [5ms]
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

Checklist before submitting a bug

• I searched issues in this repository and couldn't find such bug/problem
• I Google'd a solution and I couldn't find it
• I searched on StackOverflow for a solution and I couldn't find it
• I read the README.md file of the plugin
• I'm using the latest version of the plugin
• All dependencies are up to date with flutter pub upgrade
• I did a flutter clean
• I tried running the example project

[kaluli123123]

Draft PR #3997 fixes the iOS URI subject forwarding (signed commit 5e7542dcbd). The native URI path now passes the existing title/legacy subject to the same controller configuration used by text/files; NSURL contents and presentation/completion logic are unchanged.

Native XCTest through plugin registration and binary-channel decoding reports 2 failures / 1 pass before the fix, and 3 passes afterward on an iPhone 17 Pro simulator running iOS 26.5. The package Dart suite passes 14 with 1 existing skip; analysis reports no issues. Swift formatting, changed Objective-C regions, and diff checks pass. Independent read-only review found no blocking issues.

This verifies the actual UIActivityViewController subject value, not Mail compose UI or email delivery. Physical-device, iPad-rendering, iOS 13 and upstream cross-platform CI remain unverified. The Xcode 27 verification command used arm64/deployment-15 and a separate bundle id; the plugin's published iOS minimum was not changed. Codex assisted implementation/tests/review. I maintain the branch, which remains a draft pending contributor and platform-maintainer review; this issue remains open and nothing has been merged.