TL;DR — my_timer is now drift-free, dependency-free, and backgrounding-aware. The controller gains pause / resume / reset / seek / add / subtract plus state-inspection getters. The widget gains a modern Duration-typed API, format presets, and a custom formatter. Your 1.x code keeps compiling via deprecated aliases.

Highlights #

Breaking changes #

Existing 1.x code keeps compiling thanks to @Deprecated aliases. The only signature break is the builder parameter — rename your old builder to legacyBuilder and you're done. See the migration table in README.md.

• provider removed. State is now managed internally with ValueNotifier and rebuilt via ValueListenableBuilder. If any code was reaching into the package's internal MyTimerProvider, that type no longer exists — use MyTimerController instead.
• tickInSecond is now purely a UI refresh cadence. In 1.x it was incorrectly used as a "step size," so passing Duration(milliseconds: 500) made the timer count two seconds per real second. The new implementation tracks real time, so the displayed value is always accurate regardless of tick interval. tickInSecond is deprecated in favor of tickInterval.
• Default text format changed from HH:MM:SS to auto (picks mm:ss under an hour, hh:mm:ss under a day, dd:hh:mm:ss beyond). Pass format: TimerFormat.hoursMinutesSeconds to keep the old behavior.
• The builder parameter now uses positional Duration arguments: (BuildContext, Duration remaining, Duration elapsed) => Widget. The 1.x-style named int remainingTime builder is available under the new name legacyBuilder.

Added — controller #

• pause() — stops the ticker while preserving elapsed time.
• resume() — alias for start(); reads more naturally after pause().
• reset() — zeroes elapsed time without starting the timer.
• seek(Duration) — jumps to a position, preserving running state.
• add(Duration) / subtract(Duration) — shift elapsed time by a delta.
• isRunning, isPaused, isCompleted, isAttached — state getters.
• elapsed, remaining — read current values without a callback.

Added — widget #

• direction: TimerDirection (countUp / countDown) — modern, type-safe replacement for isIncrementing.
• duration: Duration — modern Duration-typed total. Old startTimerInSeconds / endTimerInSeconds ints remain as deprecated aliases.
• tickInterval: Duration — modern replacement for tickInSecond.
• autoStart: bool — set false to keep the timer paused until controller.start().
• onTick / onComplete — now available directly on the widget in addition to the controller.
• resyncOnResume: bool — opt-in/opt-out of the lifecycle resync hook.

Added — formatting #

• TimerFormat enum with six presets: auto, seconds, minutesSeconds, hoursMinutesSeconds, minutesSecondsMillis, daysHoursMinutesSeconds.
• formatter: String Function(Duration) — custom formatter escape hatch.
• formatDuration(Duration, TimerFormat) — exposed as a public helper for use outside the widget.

Added — engine #

• New internal MyTimerEngine (drift-free, tick-driven + wall-clock reconciled). Single source of truth for any UI built on the controller.
• MyTimerEngine.elapsed is a ValueNotifier<Duration> — power-users can subscribe directly with ValueListenableBuilder if they need more control than the widget provides.

Fixed #

• Calling controller.start() before the widget mounted threw a LateInitializationError. Method calls on an unattached controller are now safe no-ops.
• stop() followed by start() reset elapsed time inconsistently. The new pause() / resume() pair preserves state cleanly.
• The 1.0.1 widget tests asserted '00:00' while the widget actually rendered '00:00:00'. Tests now pass — all 20 of them.

Migration cheatsheet #

Added #

• Builder support — access to remainingTimeInSeconds and BuildContext for flexible UI updates.
• Provider integration — refactored MyTimer to use Provider for state management.
• New callbacks — additional callbacks on MyTimerController.
• Code refactor — improved structure and readability.

Fixed #

• Multiple timers could start without stopping the previous one.
• Reduced unnecessary setState calls.

• MyTimer widget with incrementing and decrementing modes.
• Custom tick interval via tickInSecond.
• Start / stop / complete callbacks via MyTimerController.
• Custom child widget or default time display.
• Styling options for the time display text.