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On-device vision with Camera and ML Kit in Flutter — hướng dẫn Flutter

On-device vision keeps frames private and works offline. Bài này chuyển quan sát đó thành một mô hình nhỏ để bạn có thể kiểm thử, đo lường và giữ cho code dễ bảo trì khi app lớn lên. Vấn đề cốt lõi Live barcode scan, face detect, and frame throttling. Câu hỏi hữu ích không phải API hay pattern có đẹp riêng lẻ hay không, mà là state nằm ở đâu, boundary nào chịu trách nhiệm khi lỗi xảy ra, và người dùng phục hồi thế nào khi happy path biến mất. Mô hình thực tế Throttle frame processing; do not run detectors on every camera frame. Hãy bắt đầu bằng một owner rõ ràng cho behavior. Widget chỉ nên render và phát intent; IO, persistence, permission và retry nên nằm sau một interface nhỏ. Nhờ vậy bạn có seam để fake trong test và một chỗ ghi lại các dữ kiện cần theo dõi ở production. Trong app Flutter, boundary thường có dạng: Widget phát intent như load, submit, refresh hoặc retry. Controller hoặc use case validate intent rồi gọi boundary. Boundary trả về data có kiểu hoặc failure c...

Debug, profile, and release: stop optimizing the wrong mode — hướng dẫn Flutter

Debug mode is not a performance preview. Profile mode is the truth for frames. Bài này chuyển quan sát đó thành một mô hình nhỏ để bạn có thể kiểm thử, đo lường và giữ cho code dễ bảo trì khi app lớn lên. Vấn đề cốt lõi Why jank you see in debug may not exist in release. Câu hỏi hữu ích không phải API hay pattern có đẹp riêng lẻ hay không, mà là state nằm ở đâu, boundary nào chịu trách nhiệm khi lỗi xảy ra, và người dùng phục hồi thế nào khi happy path biến mất. Mô hình thực tế Release enables tree-shaking, obfuscation, and different asserts. Hãy bắt đầu bằng một owner rõ ràng cho behavior. Widget chỉ nên render và phát intent; IO, persistence, permission và retry nên nằm sau một interface nhỏ. Nhờ vậy bạn có seam để fake trong test và một chỗ ghi lại các dữ kiện cần theo dõi ở production. Trong app Flutter, boundary thường có dạng: Widget phát intent như load, submit, refresh hoặc retry. Controller hoặc use case validate intent rồi gọi boundary. Boundary trả về data có kiểu...

A bug report template that gets mobile issues fixed — hướng dẫn Flutter

Vague bugs stall. Templates force the facts that matter. Bài này chuyển quan sát đó thành một mô hình nhỏ để bạn có thể kiểm thử, đo lường và giữ cho code dễ bảo trì khi app lớn lên. Vấn đề cốt lõi Device matrix, build number, and repro videos. Câu hỏi hữu ích không phải API hay pattern có đẹp riêng lẻ hay không, mà là state nằm ở đâu, boundary nào chịu trách nhiệm khi lỗi xảy ra, và người dùng phục hồi thế nào khi happy path biến mất. Mô hình thực tế Require build number, OS, device, and network condition. Hãy bắt đầu bằng một owner rõ ràng cho behavior. Widget chỉ nên render và phát intent; IO, persistence, permission và retry nên nằm sau một interface nhỏ. Nhờ vậy bạn có seam để fake trong test và một chỗ ghi lại các dữ kiện cần theo dõi ở production. Trong app Flutter, boundary thường có dạng: Widget phát intent như load, submit, refresh hoặc retry. Controller hoặc use case validate intent rồi gọi boundary. Boundary trả về data có kiểu hoặc failure có kiểu, không trả str...

Alternative marketplaces: EU DMA and Brazil CADE rules — hướng dẫn Flutter

Distribution rules are fragmenting by region. Bài này chuyển quan sát đó thành một mô hình nhỏ để bạn có thể kiểm thử, đo lường và giữ cho code dễ bảo trì khi app lớn lên. Vấn đề cốt lõi What changes for distribution and payments. Câu hỏi hữu ích không phải API hay pattern có đẹp riêng lẻ hay không, mà là state nằm ở đâu, boundary nào chịu trách nhiệm khi lỗi xảy ra, và người dùng phục hồi thế nào khi happy path biến mất. Mô hình thực tế Plan payment and store abstraction layers. Hãy bắt đầu bằng một owner rõ ràng cho behavior. Widget chỉ nên render và phát intent; IO, persistence, permission và retry nên nằm sau một interface nhỏ. Nhờ vậy bạn có seam để fake trong test và một chỗ ghi lại các dữ kiện cần theo dõi ở production. Trong app Flutter, boundary thường có dạng: Widget phát intent như load, submit, refresh hoặc retry. Controller hoặc use case validate intent rồi gọi boundary. Boundary trả về data có kiểu hoặc failure có kiểu, không trả string chỉ dành cho log. UI re...

Haptics and microinteractions that feel native

Small feedback loops make UIs feel expensive. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence HapticFeedback, spring curves, and when less is more. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model Match platform haptic patterns; do not invent new ones. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or use case validates the intent and calls the boun...

Melos monorepos for Flutter apps and packages

Monorepos work when bootstrap, analyze, and test are one command. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence Local path overrides, versioning, and CI scripts that scale. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model Melos is the de facto standard for Dart/Flutter multi-package repos. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or use case...

Background audio with media_kit and platform media sessions

Music and podcast apps live or die on lock-screen and Bluetooth behavior. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence Lock-screen controls, Bluetooth, and queue persistence. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model The playback engine must outlive the UI navigation stack. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or use case validat...

Material 3 Expressive theming without fighting Flutter

M3 Expressive is a design language change — theme it, do not hand-paint every widget. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence ColorScheme.fromSeed, component themes, and dynamic color on Android. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model Seed colors + component themes keep brand and accessibility in one place. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, o...

Maps, location, and permission UX in Flutter apps

Permission copy and timing decide grant rates more than the API does. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence Foreground vs background location and privacy nutrition labels. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model Request at the moment of need, with a clear benefit sentence. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or use case...

Logistics tracking UX under poor connectivity

Logistics is an offline problem wearing a map costume. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence Location batching, offline maps, and ETA honesty. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model Batch GPS and show sync state clearly. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or use case validates the intent and calls the boundary. The b...

Pseudolocales and expansion testing before translators

German and Vietnamese expand. Arabic flips. Test before paying translators. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence Finding truncation bugs without a full translation set. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model Pseudolocales catch overflow for free. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or use case validates the intent and...

Local notifications that do not spam or break on Android 13+

Notifications are a retention channel and a deletion risk. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence Channels, permissions, and scheduled reliability. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model Create channels with clear purpose; request permission at value moment. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or use case validates the ...

Marketing on-device AI without lying

Privacy marketing is regulated and scrutinized. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence What “on-device” must mean for privacy claims. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model Be precise about what leaves the device. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or use case validates the intent and calls the boundary. The boundary ...

Designing for Liquid Glass and Material without dual UIs

Platform design languages keep shifting. Adaptive wrappers absorb the shock. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence Adaptive chrome, materials, and platform-adaptive widgets. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model Share business UI; swap chrome by platform. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or use case validates the i...

Isolates and compute() without the myths

Parsing large JSON on the UI thread drops frames. Isolates help. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence What actually leaves the UI thread and what does not. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model compute() is fine for one-shot work; use long-lived isolates for streams. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or use case va...

Mobile performance interview questions that matter

Interview for diagnosis process, not memorized APIs. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence How strong candidates reason about jank and memory. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model Ask for a real jank story and what they measured. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or use case validates the intent and calls the bound...

Integration tests that survive real devices

Widget tests cannot open system dialogs. Patrol drives native UI alongside Flutter. This article turns that observation into a small implementation model you can test, measure, and keep boring when the app grows. The problem in one sentence patrol, native automation, and CI device farms for Flutter. The useful question is not whether the API or pattern looks elegant in isolation. It is where state lives, which boundary owns failure, and how a user recovers when the happy path disappears. A practical model Keep e2e to golden paths; put the rest in widget/unit tests. Start with one explicit owner for the behavior. Keep widgets responsible for rendering and user intent; keep IO, persistence, permissions, and retries behind a small interface. That gives you a seam for a fake in tests and a place to record the facts that matter in production. For a Flutter app, the boundary usually looks like this: The widget emits an intent such as load, submit, refresh, or retry. A controller or...