Fix: Failed to build iOS app with Xcode 16 and Flutter 3.x
The fix in 60 seconds: upgrade Flutter to 3.24.4 or later, raise the Podfile platform to iOS 13, wipe Pods plus DerivedData, then pod install. The error rarely lives in your Dart code.
Tag: errors
127 posts · Page 11 of 13
Fix: Unhandled Exception: FormatException: Unexpected character when parsing JSON in Dart
The fix in 30 seconds: your response body is not the JSON you think it is. Print the raw bytes, decode with utf8.decode(response.bodyBytes), and never feed an HTML error page or a BOM-prefixed string to jsonDecode.
Fix: Version solving failed in pubspec.yaml
The fix in 30 seconds: read the 'because' chain in the error, find the one constraint that boxes pub in, and either widen it or add a dependency_overrides entry. Do not start with flutter clean.
Fix: Provisioning profile doesn't include the currently selected device in MAUI iOS
The profile Visual Studio picked was generated before this iPhone's UDID was registered. Re-register the device, regenerate the development profile, redownload, redeploy.
Fix: A RenderFlex overflowed by N pixels in Flutter
The fix in 30 seconds: wrap the offending child in Expanded or Flexible. Then read the rest to learn why Row and Column do not clip, what unbounded constraints actually mean, and which fix is right for each layout.
Fix: Tool Call Arguments Did Not Match Schema in Anthropic Tool Use
Why your Claude tool call fails schema validation, in both flavours: the API rejecting your tool definition at request time, and Claude returning a tool_use block your runner cannot accept. Concrete fixes for each, with strict mode, oneOf/anyOf, additionalProperties, and the retry loop pattern.
Fix: Unable to find a valid iOS Simulator runtime during MAUI build
Xcode 15+ ships without bundled iOS simulator runtimes. MAUI fails the build when SupportedOSPlatformVersion has no matching runtime installed. Install one with xcodebuild -downloadPlatform iOS or via Xcode Settings, then verify with xcrun simctl list runtimes.
Fix: Gradle build failed to produce an .apk file in MAUI Android
Nine out of ten times the real Gradle error is buried higher in the MSBuild log. JDK 17 path, missing maui-android workload, and Windows long paths are the usual root causes.
Fix: A possible object cycle was detected
System.Text.Json refuses to serialize graphs with back-references. Set ReferenceHandler.IgnoreCycles, project to a DTO, or mark the back-pointer with [JsonIgnore]. Preserve is a last resort.
Fix: SqlException: Timeout expired during EF Core migrations
Migrations use the design-time DbContext, not your runtime CommandTimeout. Set the timeout via UseSqlServer(o => o.CommandTimeout(...)), the connection string Command Timeout, or Database.SetCommandTimeout before Migrate().