Gaber · 秒杀时钟

A precision clock for iOS that shows the system time down to the millisecond — and can float on top of any app as a Picture-in-Picture window. Built for flash sales (秒杀), ticket drops, and any moment where a second is too coarse.

一款 iOS 高精度时钟：毫秒级显示本机系统时间，并且可以通过画中画（PiP）悬浮在任意 App 之上。为秒杀、抢票、整点开抢等场景而生。

Features · 功能

• Millisecond clock / 毫秒时钟 — renders the live system time at up to 60 fps with a monospaced layout, so digits never jitter. 与系统时间实时同步，等宽字体不抖动。
• Cross-app floating window / 跨 App 悬浮窗 — one tap starts a Picture-in-Picture window that keeps showing the ticking clock while you switch to a shopping or ticketing app. 一键开启画中画悬浮窗，切到购物 / 抢票 App 后时钟仍在最上层走字。
• Keep screen awake / 保持屏幕常亮 — optionally disables the idle timer while the app is in the foreground. 可选阻止自动锁屏。
• Show / hide milliseconds / 毫秒开关 — toggle the .xxx tail when you only need seconds.
• Draggable clock card / 可拖动时钟卡片 — drag the card around (it always keeps part of itself on screen), double-tap to snap it back to center. 拖动移动时钟，双击复位。

Requirements · 环境要求

• iOS 18.0+ (iPhone & iPad)
• Xcode 16+ to build
• The floating window uses Picture-in-Picture, which is not available in the iOS Simulator — test that feature on a real device. 悬浮窗功能依赖画中画，模拟器不支持，请用真机验证。

Build & Run · 构建

git clone https://github.com/Luffky/gaber.git
cd gaber
open timer.xcodeproj        # then ⌘R in Xcode

Or from the command line:

xcodebuild -project timer.xcodeproj -scheme timer \
  -destination 'platform=iOS Simulator,name=iPhone 17 Pro' build

How the floating clock works · 悬浮窗原理

iOS has no general-purpose overlay API, so Gaber uses the system Picture-in-Picture pipeline to float across apps:

1. PictureInPictureClock draws the current time into a CVPixelBuffer with Core Graphics, 30 times per second.
2. Each frame is wrapped in a CMSampleBuffer and enqueued on an AVSampleBufferDisplayLayer.
3. That layer backs an AVPictureInPictureController (ContentSource(sampleBufferDisplayLayer:playbackDelegate:)), so the system treats the clock as a live video and hosts it in the PiP window above other apps.
4. The audio background mode (“Audio, AirPlay, and Picture in Picture”) keeps rendering alive while the app is in the background.

iOS 没有通用的悬浮窗 API，Gaber 借助系统画中画通道实现跨 App 悬浮：每秒 30 次用 Core Graphics 把时间画进 CVPixelBuffer，封装为 CMSampleBuffer 送入 AVSampleBufferDisplayLayer，再由 AVPictureInPictureController 作为“视频”托管到画中画窗口。

Project layout · 目录结构

timer/
├── timerApp.swift              # @main entry point
├── ContentView.swift           # Clock UI, settings, PiP controls
├── PictureInPictureClock.swift # PiP controller + 30 fps frame renderer
├── Info.plist                  # Background modes (audio, PiP)
└── Assets.xcassets             # App icon, accent color
timer.xcodeproj                 # Xcode project (scheme: timer)
docs/                           # Release / App Store notes

Releasing · 发布

See docs/RELEASE.md for the App Store checklist — bundle ID / signing, versioning, privacy manifest, export compliance, and App Review notes specific to the PiP clock.

Author

Made by @Luffky (gab). App Store publishing assistance by friends.