上一篇：<a href="https://mistjere.com/article/023605">假如我年少有為知進退－還在踩坑的Flutter(1)</a> (1) idevice_id cannot run on catalina<a href="https://github.com/flutter/flutter/issues/42302">https://github.com/flutter/flutter/issues/42302</a>這是在升版至catalina後出現的一個坑<blockquote>sudo xattr -d com.apple.quarantine /PATH_TO_YOUR_FLUTTER_HOME/bin/cache/artifacts/libimobiledevice/idevice_idsudo xattr -d com.apple.quarantine /PATH_TO_YOUR_FLUTTER_HOME/bin/cache/artifacts/libimobiledevice/ideviceinfosudo xattr -d com.apple.quarantine /PATH_TO_YOUR_FLUTTER_HOME/bin/cache/artifacts/usbmuxd/iproxy </blockquote>(2)Error connecting to the service protocol: failed to connect to http://127.0.0.1:1024/eiemy-q0vh0=/<a href="https://github.com/flutter/flutter/issues/47204#issuecomment-570832706">https://github.com/flutter/flutter/issues/47204#issuecomment-570832706</a> (3)firebase_messaging 6.0.9<a href="https://stackoverflow.com/questions/60356601/flutter-firebase-messaging-6-0-9">https://stackoverflow.com/questions/60356601/flutter-firebase-messaging-6-0-9</a>這個只是一個懶惰的坑。在<a href="https://pub.dev/packages/firebase_messaging">pub.dev</a>上的readme完全沒有要更新的意思，新/舊的AppDelegate.swift不同卻誤導人更新錯成舊的版本，build的時候就失敗。我的解決方法就是直接去<a href="https://github.com/FirebaseExtended">FirebaseExtended</a>/<a href="https://github.com/FirebaseExtended/flutterfire">flutterfire</a>的github <a href="https://github.com/FirebaseExtended/flutterfire/tree/master/packages/firebase_messaging/example">firebase_messaging/example</a>看。 (4)flutter build ios --release may use a debug Flutter.framework by mistake這個錯誤蠻可惡的，在flutter v1.9.1時Flutter.framework在build release前只執行flutter clean是不夠的，還要手動移除ios/Flutter/Flutter.framework，在build的時候才會重新產出<blockquote>flutter cleanrm -rf ios/Flutter/Flutter.frameworkflutter build ios --release</blockquote> (5)[App.framework] Linked and embedded framework "App.framework" was built for iOS/iOS Simulator手動移除App.framework即可。解決來源：<a href="https://github.com/flutter/flutter/issues/50568#issuecomment-584996079">https://github.com/flutter/flutter/issues/50568#issuecomment-584996079</a><blockquote>rm -rf ios/Flutter/App.framework</blockquote> (6)Building for iOS, but the linked and embedded framework "App.framework" was built for iOS Simulator.&nbsp; <a href="https://flutter.dev/docs/development/ios-project-migration">https://flutter.dev/docs/development/ios-project-migration&nbsp;</a> You might be directed to this page if Flutter detects that your project doesn"t support Xcode 11.4.解決方法：(1) 閉嘴等待更新<blockquote>v1.15.3 and later automatically migrates your Xcode project.</blockquote>(2) 手動修改- From the Flutter app directory, open ios/Runner.xcworkspace in Xcode.- In the Navigator pane, locate the Flutter group and remove App.framework and Flutter.framework.- In the Runner target build settings Build Phases &gt; Link Binary With Libraries confirm App.framework and Flutter.framework are no longer present. Also confirm in Build Phases &gt; Embed Frameworks.- Change the Runner target build settings Build Phases &gt; Thin Binary script as follows:<blockquote>/bin/sh "$FLUTTER_ROOT/packages/flutter_tools/bin/xcode_backend.sh" embed&nbsp; /bin/sh "$FLUTTER_ROOT/packages/flutter_tools/bin/xcode_backend.sh" thin&nbsp;</blockquote>- In the Runner target Build Settings &gt; Other Linker Flags (OTHER_LDFLAGS) add $(inherited) -framework Flutter. (7)Warning! This package referenced a Flutter repository via the .packages file that is no longer available. The repository from which the "flutter" tool is currently executing will be used instead.<a href="https://github.com/flutter/flutter/issues/21435">https://github.com/flutter/flutter/issues/21435</a>解決方法：<a href="https://github.com/flutter/flutter/issues/21435#issuecomment-479747784">https://github.com/flutter/flutter/issues/21435#issuecomment-479747784</a>移除.packages。 (8)vscode could not find flutter sdk<a href="https://stackoverflow.com/questions/56845375/vscode-could-not-find-a-flutter-sdk">https://stackoverflow.com/questions/56845375/vscode-could-not-find-a-flutter-sdk</a> <blockquote><ol><li>Open up Terminal. Run the following command: sudo nano /etc/paths</li><li>Enter your password, when prompted.</li><li>Go to the bottom of the file, and enter the path you wish to add.</li><li>Hit control-x to quit.</li><li>Enter “Y” to save the modified buffer.</li></ol></blockquote> (9)type "List" is not a subtype of type "List"<a href="https://stackoverflow.com/questions/49603021/type-listdynamic-is-not-a-subtype-of-type-listwidget">https://stackoverflow.com/questions/49603021/type-listdynamic-is-not-a-subtype-of-type-listwidget</a><blockquote>type "List&lt;dynamic&gt;" is not a subtype of type "List&lt;Widget&gt;"</blockquote>這算是開發上很常見的一個錯誤，追根究底還是因為dart 2.0的強模式引發的強型別限制。<blockquote>data.map&lt;Widget&gt;((arg) =&gt; Widget(arg)).toList()</blockquote><blockquote>The more complicated answer is that while the type of children is List&lt;Widget&gt;, that information doesnt flow back towards the map invocation. This might be because map is followed by toList and because there is no way to type annotate the return of a closure.</blockquote> (10)await Geolocator().getCurrentPosition blocks.<blockquote>I am seeing this issue after upgrading to Xcode 11.4. Tried 3 location libraries now, all broken on iOS.</blockquote>使用<a href="https://github.com/Baseflow/flutter-geolocator">flutter-geolocator</a>造成的一個錯誤。解決方法是將參數LocationAccurracy改成最高。不過要注意在iOS模擬器上是無法偵測地理位置的。<blockquote>In my case, changing LocationAccurracy from low to best solved the issue.</blockquote> (11)Yellow lines under Text Widgets in Flutter?這個問題在開發初期我一直很在意，但是一直沒看到類似的關鍵字。直到有一天我上架到App Store後發現，release版本竟然也會出現這個東西，我才驚覺原來這不是debug模式下才會出現的。那就有必要處理了。比較常見的情況是在Hero組件上實現動態文字(fontSize, fontWeight)。其原因是高置位沒有Scaffold，或是將Hero前後的Text()的所有color, fontSize, fontWeight都自定義起來，就能避免render過程中引發的warning text underline annotation。<blockquote>The problem is not having a Scaffold or not. Scaffold is a helper for Material apps (AppBar, Drawer, that sort of stuff). But you are not forced to use Material.What you"re missing is an instance of Theme as a parent.</blockquote><a href="https://stackoverflow.com/questions/47114639/yellow-lines-under-text-widgets-in-flutter">https://stackoverflow.com/questions/47114639/yellow-lines-under-text-widgets-in-flutter</a> (12) Getting error in Flutter Share only on iPad<a href="https://github.com/flutter/flutter/issues/44962">https://github.com/flutter/flutter/issues/44962</a>這個錯誤是我在測試iPad分享功能的時候發現的。原以為在iOS上實現share功能是大同小異的，沒想到在新版iPad上的行為不太一樣，他的分享不是像iPhone一樣從螢幕下方跳出半版面的分享畫面功能，而是從點擊位置的左下/右下/左上/右上跳出一個自定義尺吋的分享小框。因此需要另外實作iPad版本的share組件。<blockquote>await Share.share( &nbsp; "App Name", &nbsp;sharePositionOrigin: Rect.fromCenter(center: Offset(100, 100), width: 100, height: 100), )</blockquote> (13)Sign with apple今年初Apple再度更新app store的上架規範，新增了一條規定，總之就是說如果你有登入功能請務必實作apple sign in。(我就曾經收到一封上架reject的信，只有提供google/facebook登入而被拒絕囧)後來使用了<a href="https://pub.dev/packages/apple_sign_in">apple_sign_in</a>總之他的實作過程不是很輕鬆，要依照文件將sign in apple的capability加入並在firebase的authentication中取得service id。參考實作：<a href="https://codewithandrea.com/videos/2020-01-20-apple-sign-in-flutter-firebase/">https://codewithandrea.com/videos/2020-01-20-apple-sign-in-flutter-firebase/</a> (14)pytorch Failure [INSTALL_FAILED_INSUFFICIENT_STORAGE]我和大學同學一起寫的植物辨識用到了<a href="https://pub.dev/packages/torch_mobile">torch_mobile</a>，由facebook開發的可在android上運行pytorch訓練的模型(.pt)，然後有大神把他包成flutter的package。遇到的問題其實和這沒有太大關係，總之他會發生錯誤的原因是因為記憶體不足。可以在yaml檔案中的assets將必要的檔案加入至assets就好，不要全部都無腦丟進去。這樣或許很方便，但是會造成不必要的開發時間成本。像這些ckpt的模型都50mb上下，又一次丟十幾個模型進來的話就會很肥。參考文章：<a href="https://www.itread01.com/content/1550526334.html">https://www.itread01.com/content/1550526334.html</a> (15)Error: Unfortunately you cant have non-Gradle Java modules and &gt; Android-Gradle modules in one project解決方法：<a href="https://stackoverflow.com/questions/28668252/android-studio-error-unsupported-modules-detected-compilation-is-not-supported">https://stackoverflow.com/questions/28668252/android-studio-error-unsupported-modules-detected-compilation-is-not-supported</a><blockquote>1- close the project2- close Android Studio IDE3- delete the .idea directory4- delete all .iml files5- open Android Studio IDE and import the project</blockquote> (16)Error: The method "CachedNetworkImageProvider.load" has fewer positional arguments than those of overridden method "ImageProvider.load"如果你想做圖片快取功能，你可能會選擇<a href="https://github.com/Baseflow/flutter_cached_network_image">flutter_cached_network_image</a>作為你的最佳選擇方案。然後就可能會遇到這個問題。解決方法：<a href="https://github.com/Baseflow/flutter_cached_network_image/issues/270#issuecomment-544573654">https://github.com/Baseflow/flutter_cached_network_image/issues/270#issuecomment-544573654</a><blockquote>翻譯：不要問，用2.0.0-rc就對了。</blockquote> (17)Why does my text not wrap?這也是我最最最常遇到的問題TOP 10。我覺得他的設計還需要再改變就是了，畢竟很不直觀。文字不會換行，在手機上是很糟糕的閱讀體驗。解決發法：<a href="https://github.com/flutter/flutter/issues/4128#issuecomment-355145784">https://github.com/flutter/flutter/issues/4128#issuecomment-355145784</a><blockquote>return new MaterialApp( &nbsp; &nbsp; &nbsp; &nbsp;home: new Center( &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;child: new Row(children: &lt;Widget&gt;[ &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;new Flexible( &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;child: new Column( &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;crossAxisAlignment: CrossAxisAlignment.start, &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;children: &lt;Widget&gt;[ &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;new Text( "Why doesnt this text wrap? There is plenty of vertical space...") &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;] ) )]) ) )</blockquote>不過還有非常多情況以上的方法是無效的。只能自己去發現其中的奧妙。 -----------------------------FLUTTER社群加油!